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List of Tables

2.1

AC Measurement Configurations . . . . . . . . . . . . . . .

6

2.2

DC Measurement Configurations . . . . . . . . . . . . . . .

7

2.3

RS-232C Port Pinout / Signal Description . . . . . . . . . .

10

2.4

931A Reset Selection Screen . . . . . . . . . . . . . . . . . .

12

3.1

Phase Angle Preferences . . . . . . . . . . . . . . . . . . . .

20

3.2

Channel 2, AC Voltage Ranges, Vrms

. . . . . . . . . . . .

23

3.3

Channel 2, AC Current Ranges, Arms . . . . . . . . . . . .

23

3.4

Channel 2, DC Voltage Ranges, Vdc . . . . . . . . . . . . .

23

3.5

Channel 1, AC Voltage Ranges, Vrms

. . . . . . . . . . . .

37

3.6

Channel 1, AC Current Ranges, Arms . . . . . . . . . . . .

37

3.7

Channel 1, DC Voltage Ranges, Vdc . . . . . . . . . . . . .

37

3.8

Phase Convention . . . . . . . . . . . . . . . . . . . . . . . .

54

B.1 Custom Data Table . . . . . . . . . . . . . . . . . . . . . . . 132

xv

Summary of Contents for 931A

Page 1: ...ETUP SCALE ESCAPE ENTER VOLTS AMPS PHASE FREQUENCY POWER VARS VA PF HARMONICS WAVEFORM CHANNEL 1 SELECT CHANNEL 2 SELECT MEASURE HOLD CH2 RANGE MIN MAX TRANSDUCER MENU LOG DATA PRINT LAST SETUP CH1 CH2 ON OFF FUSE 1AF 250V 85 264 Vac 47 440 Hz 110 250 Vdc RS 232 GROUND BEFORE USE DISPLAY CONFIG ARM RESET A B C N 750 Vrms 1000 Vdc MAX 20 Arms MAX 10Vdc MAX 100mAdc MAX A B 300V MAX A B Arbiter Syste...

Page 2: ...tion This manual describes the Model 931A Power System Analyzer and accessories Firmware and Firmware Updates This manual was created based on the following firmware Copyright Program 10 February 2010 Help Version 25 JUNE 1996 DSP Version 093098 The firmware versions indicated above are displayed on the Model 931A at startup To freeze the display during this screen press and hold the ESCAPE key un...

Page 3: ...ility designated by Arbiter Systems Buyer shall prepay all shipping charges duties and taxes to send the product to Arbiter Systems and Buyer shall prepay shipping charges duties and taxes to return the product to Buyer THE WARRANTY SET FORTH HEREIN CONSTITUTES THE ONLY WARRANTY OBLIGATIONS OF ARBITER SYSTEMS EX PRESSED OR IMPLIED STATUTORY BY OPERATION OF LAW OR OTHERWISE ARBITER SYSTEMS DISCLAIM...

Page 4: ...CEED AS FOLLOWS 1 Notify Arbiter Systems Inc specifying the instrument model number and serial number and giving full details of the difficulty Service data or instrument return authorization will be provided upon receipt of this information 2 If instrument return is authorized forward prepaid to the manufac turer If it is determined that the instrument is not covered by this warranty an estimate ...

Page 5: ...Chapter 2 Functional Description Chapter 3 Operation Chapter 4 Specifications Appendix A RS 232 Commands Appendix B Optional Accessories Appendix C CE Mark Certification Index Copyright Arbiter Systems Incorporated September 2021 All rights re served International copyright secured PD0017400T Reorder Number AS0094000 v ...

Page 6: ...vi ...

Page 7: ...annels 5 2 4 Measurement Method 6 2 4 1 Sampling and Filtering 8 2 5 User Interface 8 2 5 1 Graphics Display 8 2 5 2 Keypad 9 2 6 RS 232C Interface 9 2 7 Power Supply and Battery 9 2 7 1 Battery Power 9 2 7 2 Line Power Battery Charging 10 2 7 3 Auto Shutdown Mode 11 2 8 Start Up Sequence 11 2 8 1 Holding the Start Up Sequence 11 2 8 2 Reset Instrument Default Setup 11 3 Operation 13 3 1 Introduct...

Page 8: ...ent 52 3 6 2 Active Power Reactive Power 54 3 6 3 Apparent Power Power Factor 56 3 6 4 Waveform Display 58 3 7 Timer Measurements 58 3 7 1 Connecting the Inputs 59 3 7 2 Configuring the Timer 59 3 7 3 Timer Measurement Categories 62 3 8 Transducer Testing 64 3 8 1 Configuring the Transducer 64 3 8 2 Connecting the Inputs 70 3 8 3 Connecting the Outputs 75 3 8 4 Performing the Measurement 75 3 8 5 ...

Page 9: ...dwidth 102 4 3 2 Memory 102 4 3 3 Display 102 4 3 4 Keypad 102 4 3 5 Environment 102 4 3 6 Input Power 103 4 3 7 Serial Port 103 A RS 232C Commands 105 A 1 Introduction 105 A 2 Serial Port Examples 106 A 3 Command Summary 107 A 3 1 Battery Charging Status BAT 107 A 3 2 Backlight Set BLT 107 A 3 3 Channel Calibrate CCH 107 A 3 4 Ratio CH1 CH2 CCR 108 A 3 5 Channel Input Select CHS 108 A 3 6 Calibra...

Page 10: ...5 A 3 29 Phase Mode Set PHM 116 A 3 30 Phase Return PHS 116 A 3 31 Power Return PWR 116 A 3 32 Range Hold Set RHD 117 A 3 33 Logged Data Review RLD 117 A 3 34 Range Hold Release RRH 117 A 3 35 MIN MAX Restart RST 117 A 3 36 Transducer Channel SCC 118 A 3 37 Serial Number SER 118 A 3 38 Flash Log SLO 118 A 3 39 Scale On Off SOO 119 A 3 40 DSP Speed SPD 119 A 3 41 Phase Preference Set SPH 119 A 3 42...

Page 11: ...s 127 B 1 Precision Current Transformer 127 B 1 1 Specifications 127 B 1 2 Input Connections 127 B 1 3 Current Display 128 B 2 Handle Bail 128 B 2 1 Parts and Accessories 128 B 2 2 Required Tools 128 B 2 3 Procedure 128 B 2 4 Operation 128 B 3 Extended Memory 129 B 3 1 Data Organization 130 B 3 2 Computing the Number of Files and Records 132 B 3 3 Log Data Triggering 133 B 3 4 Front Panel Operatio...

Page 12: ...xii ...

Page 13: ...3 3 8 1 Phase 2 Wire 1 Element Connections 34 3 9 1 Phase 3 Wire 2 Element Connections 34 3 10 3 Phase 3 Wire 2 Element Connections 35 3 11 3 Phase 4 Wire 2 5 Element Connections 35 3 12 3 Phase 4 Wire 3 Element Connections 36 3 13 Phase Angle Example 54 3 14 1 Phase 2 Wire 1 Element Transducer Test 71 3 15 1 Phase 3 Wire 2 Element Transducer Test 72 3 16 3 Phase 4 Wire 2 5 Element Transducer Test...

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Page 15: ...set Selection Screen 12 3 1 Phase Angle Preferences 20 3 2 Channel 2 AC Voltage Ranges Vrms 23 3 3 Channel 2 AC Current Ranges Arms 23 3 4 Channel 2 DC Voltage Ranges Vdc 23 3 5 Channel 1 AC Voltage Ranges Vrms 37 3 6 Channel 1 AC Current Ranges Arms 37 3 7 Channel 1 DC Voltage Ranges Vdc 37 3 8 Phase Convention 54 B 1 Custom Data Table 132 xv ...

Page 16: ...xvi ...

Page 17: ...sion measurement of these AC parameters Powered by either an internal rechargeable battery or by AC line voltage the Model 931A is truly portable This manual is divided into four chapters and two appendices as follows Chapter 1 General Information Chapter 2 Functional Description Chapter 3 Operation Chapter 4 Specifications Appendix A RS 232C Commands Appendix B Optional Accessories 1 2 Supplied E...

Page 18: ...udes AS0036000 Mounting Bracket AP0012800 1000 1 Clamp on CT 200 Amps AP0012900 250 5 500 5 1000 5 Clamp on CT 1000 Amps AP0001300 1000 1 1000A 600V Cat III EN61010 811AT CT 3 Phase Universal Test Plug Current Lead Set 813AT BT 3 Phase Safety Voltage Lead Set 815AT BT 3 Phase Fused Voltage Lead Set 816AT CT 3 Phase Spade lug Current Lead Set 817AT 3 Phase CT Lead Set red yellow blue This is a part...

Page 19: ...put voltages of up to 750 Vrms or 1000 Vdc Each input voltage terminal is isolated from signal common with an impedance of 1 megohm and is physically isolated from the chassis 2 2 2 Current The 931A features three independent transformer coupled AC current inputs accessible via three pairs of front panel binding posts which are color coded for polarity and labeled A B and C Each terminal can accep...

Page 20: ...ESCAPE ENTER VOLTS AMPS PHASE FREQUENCY POWER VARS VA PF HARMONICS WAVEFORM CHANNEL 1 SELECT CHANNEL 2 SELECT MEASURE HOLD CH2 RANGE MIN MAX TRANSDUCER MENU LOG DATA PRINT LAST SETUP CH1 CH2 ON OFF FUSE 1AF 250V 85 264 Vac 47 440 Hz 110 250 Vdc RS 232 GROUND BEFORE USE DISPLAY CONFIG ARM RESET A B C N 750 Vrms 1000 Vdc MAX 20 Arms MAX 10Vdc MAX 100mAdc MAX A B 300V MAX A B Figure 2 1 Model 931A Fr...

Page 21: ...ng Display results of timer measurements in either seconds or cycles 2 3 Measurement Channels The Model 931A incorporates two measurement channels referred to as Channel 1 and Channel 2 Multiplexing of the voltage and current inputs makes it possible to connect them to one or both of these measurement channels in different configurations Figure 2 2 illustrates multiplexing of voltage and current i...

Page 22: ...onfiguration Measured Input Referenced To Va b Voltage A Voltage input B Vb c Voltage B Voltage input C Vc a Voltage C Voltage input A Va c Voltage A Voltage input C Vc b Voltage C Voltage input B Vb a Voltage B Voltage input A Va n Voltage A Voltage input N Vb n Voltage B Voltage input N Vc n Voltage C Voltage input N Va s Voltage A Synthesized neutral Vb s Voltage B Synthesized neutral Vc s Volt...

Page 23: ...Mode simulates the operation of an extremely accurate analog rms detector or analog multiplier Therefore measurements made in wide band include the effect of harmonics within the instrument s 3 05 kHz bandwidth The Narrow Band Mode is a completely different measurement pro cess Through proprietary DSP state estimation algorithms it accurately estimates the parameters viz frequency magnitude and ph...

Page 24: ... 12 5 Ks s allowing accurate measurements at frequencies down to 5 Hz The record length under these conditions is 655 ms The Model 931A completes a measurement cycle 2 to 3 times per second The cycle includes collecting data processing and displaying results A faster update rate of 4 to 5 times per second is achieved by initiating the Fast Mode Pressing the shift key twice or issuing the SPD RS 23...

Page 25: ... Table 2 3 lists the connector types pin locations and signal descriptions for the RS 232C port of the Model 931A and other devices Once properly set up a host computer may assume total control All functions and data available from the front panel are also available to the host computer All commands consist of three letter commands preceded in some cases by setup parameters separated by commas The...

Page 26: ...to the instrument and increases the time to charge the NiMH battery To charge the battery completely from a depleted state should take approximately 8 hours with the Model 931A powered off Charge only if ambient temperature is in the range 0 C 40 C 32 F 104 F NiMH battery charging in the Model 931A is monitored and controlled using three factors 1 T t 2 V t and 3 time T t When the cell reaches ful...

Page 27: ...ayed as a decimal number with the format MMDDYY The second part of the sign on display shows the ROM program copyright date the Help ROM version date and the DSP ROM version date The DSP ROM date is displayed as a decimal number in the format MMDDYY As new features are added to the Model 931A these dates are updated 2 8 1 Holding the Start Up Sequence Holding the escape key during the startup sequ...

Page 28: ...start the unit 2 Press and release the ENTER key when the first display screen becomes visible 3 Using the Cursor keys up or down arrows select PARTIAL from the three options shown in Table 2 4 4 Press ENTER and the instrument should ask ARE YOU SURE YES UP NO DOWN Press the UP arrow to complete the reset procedure Otherwise press the DOWN arrow to escape 5 The display should indicate the message ...

Page 29: ... Eleven of the front panel banana jacks are recessed and insulated for safety at high voltages The remaining seven jacks are of a type suitable for high current applications The following paragraphs describe the functions of each of these connectors 3 2 1 Chassis Ground A ground lug located in the lower right hand corner of the front panel is connected to the instrument chassis and also to the saf...

Page 30: ... for measurement of voltages up to 750 Vrms or 1000 Vdc between inputs The 1 megohm input voltage dividers are tied to a common point Any unused voltage inputs will float at the average value of the used inputs Safety insulated banana jacks are used for the connections Measure voltage between any two of the inputs e g A and N Also the 931A will measure voltage between the input and a synthesized n...

Page 31: ...ts are provided via two pairs of insulated banana jacks with the inputs being independently and optically coupled The timer is designed for testing of protective relays and other similar or related tasks 3 3 Front Panel Keys The following paragraphs describe the functions and features that can be accessed via Front Panel Keys The functions of the keys in the main keyboard are divided into three gr...

Page 32: ...ntaneous sampled values determines the true rms amplitude It includes harmonics up to 3 05 kHz and removes DC prior to calculation In narrow band mode an extremely accurate proprietary digital signal processing DSP algorithm determines the fundamental amplitude It also excludes the effects of DC harmonics and noise 3 3 1 2 Phase Frequency Setup 2 PHASE FREQUENCY Press the PHASE FREQUENCY key to di...

Page 33: ...ng the vector difference of the wide band apparent power less the active power active power is described above The wide band apparent power is the product of the wide band rms voltage and the wide band rms current 3 2 Wide band V ARs p V A2 W2 Mathematically reactive power is defined as the square root of the quantity apparent power squared minus active power squared The sign of the wide band reac...

Page 34: ...and mode apparent power volt amps or VA is determined by multiplying the wide band rms voltage by the wide band rms current Power factor is determined by dividing the wide band active power by the wide band apparent power refer to Section 3 3 1 3 In narrow band mode apparent power is determined by multiplying the fundamental amplitude of the voltage and the current accurately by DSP Power factor i...

Page 35: ...F 0 Lead Vars 1 0 VA W 0 Current Lags Voltage Current Leads Voltage Conventions Used in the 931A NOTES Polarity for CH2 Lagging CH1 CH1 Voltage CH2 Current NARROW BAND Power Factor Cos q Vars Vfund Ifund Sin q Watts Vfund Ifund Cos q VA Vfund Ifund Where q Theta Phase Angle between voltage and current A negative number indicates that current is lagging voltage WIDE BAND Power Factor Watts VA VA Vr...

Page 36: ...red Reactive Power VARS Received Reactive Power VARS Delivered Power Factor LAG Power Factor LAG Power Factor LEAD Power Factor LEAD Figure 3 2 Phase Power Factor VAR Quadrants Phase Convention Quadrant I Quadrant II Quadrant III Quadrant IV CH2 Lagging CH1 for 180 0 to 90 90 to 180 180 to 90 90 to 0 for 180 0 to 90 90 to 180 180 to 90 90 to 0 for 0 360 360 to 270 270 to 180 180 to 90 90 to 0 for ...

Page 37: ...undamental frequency Select any harmonic with the movable cursor found in the graphic display using the arrow keys The display also shows corresponding numerical values of the amplitude and the phase angle of the harmonic relative to fundamental Press CHANNEL 1 SELECT or CHANNEL 2 SELECT to toggle the display between the signals applied to Channels 1 or 2 Numerical display of THD and K factor are ...

Page 38: ...ly one signal it must be connected to Channel 1 If analyzing a single highly distorted waveform connect a reference signal of the same fundamental frequency to Channel 1 and the waveform to be analyzed to Channel 2 Combinations from the front panel inputs allow twenty seven choices three AC currents A B C twelve AC voltages and twelve DC voltages Each voltage terminal may be referenced to any othe...

Page 39: ...surement Hold mode is active Two other methods of activating the Measurement Hold mode is by reviewing Logged Data or by the Timer Stop Gate see 3 7 2 5 3 3 1 10 CH2 Range CH2 RANGE CH1 RANGE Press the CH2 RANGE key to select the operating voltage or current range for Channel 2 The ranges are only approximate and vary from unit to unit Range values allow selection of either auto range or a fixed r...

Page 40: ... ure the Model 931A to display the transducer input magnitude as either the actual measured quantity or as a percentage of full scale Likewise display the transducer output level as either the measured quantity or percentage of full scale or as a percent error based on the input and output ranges Prior to initiation of Transducer measurements the Model 931A automatically performs a self calibratio...

Page 41: ...tput of the selected print option at various time intervals Auto Log Setup Shows up only when 16 Mbyte memory card is installed See Section B 3 4 for details 3 3 1 14 Log Data LOG DATA REVIEW Press the LOG DATA key to store measurement data to non volatile memory Stored data includes current time and date according to the built in real time clock The memory location in which data is stored will be...

Page 42: ...hen using the CH1 CH2 function any scaling factors for magnitude and or phase will apply to the displayed result see Section 3 3 2 17 for a discussion of scaling factors CH1 CH2 is useful for checking the amplitude and phase angle ac curacy of current transformers Connect the primary in series with a Model 931A current input and set that input to Channel 1 Connect the transformer secondary to anot...

Page 43: ... algo rithms in which harmonics are ignored Refer to the help screens for each individual measurement for more detailed descriptions Channel 1 is used as the internal reference Use Channel 1 if only one signal is measured If measuring both a current and a voltage use Channel 1 for measuring the voltage and Channel 2 for the current 3 3 2 4 Wide Band CHANNEL 2 SELECT BAND WIDE Press the BAND WIDE k...

Page 44: ...he 3 phase Measurement Selection menu Amplitude power and phase quantities for the individual phases are shown along with the totals for the system In the right column the screen identifies totals by a T energy readings by H and as averages by a The sample Tabular display below identifies the individual quantities Values for Va and Ia Values for Vc and Ic Combined Values Phase Sequence Indication ...

Page 45: ...hich is the average of the signals present at voltage inputs a b and c Results are accurate for active power but to estimate apparent power synthesized neutral is used and accuracy depends on symmetry of the phase voltages Reactive power power factor and phase angle also are estimated VasVbs phase is measured to determine phase rotation In 3 phase 4 wire 3 element mode the instrument sequences bet...

Page 46: ... a length of less than one pixel is not displayed All voltage and current phases are made with respect to the A phase voltage The A phase voltage must be present for a proper Vector Diagram display 3 3 2 8 Voltage and Current Sequence The Voltage and Current Sequence display shows the measured voltages currents and phase angles in the top portion of the display The bottom half of the display shows...

Page 47: ...ic of unbalanced 3 phase four wire systems and correlate to neutral shift where there is a current and potential difference in motor or generator windings with respect to system ground Zero Sequence conditions result from unequal phase to neutral parameters 31 ...

Page 48: ...Tabular with Power Vector Diagram Voltage and Current Sequence Waveform Figure 3 6 Three Phase Displays for an ABC System 32 ...

Page 49: ...Tabular with Power Vector Diagram Voltage and Current Sequence Waveform Figure 3 7 Three Phase Displays for a CBA System 33 ...

Page 50: ...3 3 2 9 System Connections SOURCE LOAD N L Figure 3 8 1 Phase 2 Wire 1 Element Connections SOURCE LOAD N L1 L2 Figure 3 9 1 Phase 3 Wire 2 Element Connections 34 ...

Page 51: ...SOURCE LOAD B A C Figure 3 10 3 Phase 3 Wire 2 Element Connections SOURCE LOAD B A C N Figure 3 11 3 Phase 4 Wire 2 5 Element Connections 35 ...

Page 52: ...SOURCE LOAD B A C N Figure 3 12 3 Phase 4 Wire 3 Element Connections 36 ...

Page 53: ... Ranges Vrms 0 0 09 0 32 0 75 2 56 5 97 0 08 0 18 0 64 1 49 5 12 11 9 0 16 0 37 1 28 2 98 10 24 20 0 Table 3 6 Channel 1 AC Current Ranges Arms 0 5 17 40 135 8 320 4 2 10 34 80 271 5 640 8 5 20 68 160 543 1000 Table 3 7 Channel 1 DC Voltage Ranges Vdc When an input signal exceeds the upper limit of a range which is held the numbers in the display will change to dashes and the message Channel 1 Ove...

Page 54: ... other sub menus which allow for various transducer test configurations Once all parameters have been set press ESCAPE and Transducer Operation will begin See Section 3 8 for further information on transducer testing 3 3 2 13 Help MENU HELP Press SHIFT then the HELP key to find reference information about the functions of the Model 931A To get help for a specific function press SHIFT then HELP fol...

Page 55: ...then PRINT LOG to print to a list of the stored records to printer or computer connected to the serial interface RS 232 port 3 3 2 16 Store Setup LAST SETUP STORE SETUP Use the STORE SETUP key to save the current instrument state in one of six memory registers SETUP 1 through SETUP 6 Press SHIFT then STORE SETUP to produce the following prompt on the display Press SHIFT and desired SETUP key to st...

Page 56: ...lay then shows the magnitude and phase scale factors for each of the input functions as seen below For magnitude the factor represents the number by which a measured value is multiplied during the measurement process For example a magnitude scale factor of 100 with 10 volts applied to the Model 931A input displays 1000 volts Therefore if the Model 931A was used to measure the voltage at the output...

Page 57: ...power quantities by using complex multiplication The accuracy of this method depends on the absence of significant harmonic power and the size of the phase offset 3 3 3 Data Entry Functions When performing operations which require modification of parameters or making selections from menus the arrow keys in the top row of the keyboard are used for cursor movement as described in the following parag...

Page 58: ... function 3 3 3 5 Right Arrow Use the right arrow key to move the display cursor right The cursor movement function associated with this key is automatically enabled as required After making a menu selection this key will return to its primary function 3 3 3 6 Enter Press the ENTER key to make menu selections and accept modified numbers 3 3 3 7 Escape Press the ESCAPE key to back out of menus or s...

Page 59: ...Config Press the CONFIG key to display the timer configuration menu which appears as follows One or more sub menus follow each of the menu selections which allow configuration of the specific functions Section 3 7 provides more detailed information about the timer sub menus and their functions 3 3 4 3 Arm Reset Use the ARM RESET key to arm and reset the active timer Once stopped pressing the ARM R...

Page 60: ...Direct Measurements For measurement of certain parameters the Model 931A computes results from one or both channels individually Always use Channel 1 if only one input signal is present These measurement parameters include the following AC Voltage AC Current DC Voltage Frequency Harmonics Waveform The following sections provide instructions for performing measure ments of parameters within this gr...

Page 61: ...e measurement channel and to display the following menu Arrows form the cursor highlighting one of the selections Press the arrow keys to locate the measurement value For example using the arrow keys move the cursor to Van to measure an AC voltage between inputs A and N Press the ENTER key to confirm the selection Measure two separate voltages concurrently by configuring both Chan nels 1 and 2 For...

Page 62: ...both a current and a voltage are measured Channel 1 should be used for the voltage and Channel 2 for the current 3 5 2 AC Current Measurement The Model 931A can directly measure and display AC currents of up to 20 Arms It can measure higher currents using a current transformer CT and with direct readout using the scaling feature see Scale in Section 3 3 2 17 3 5 2 1 Input Connections The Model 931...

Page 63: ...ured by Channel 1 The number below it corresponds to the current value measured by Channel 2 The display indicates the general measurement bandwidth i e Wide Band near the lower left hand corner The Model 931A uses either wide band or narrow band mode to measure and display AC voltage Select measurement bandwidth by pressing SHIFT followed by either NARROW BAND or BAND WIDE Press SHIFT then BAND W...

Page 64: ...urements between two or more of the voltage terminals The ground lug is included for safety purposes only 3 5 3 2 Configuring the Channels Configure the chosen measurement channel after connecting the voltage to the appropriate input terminals Configure Channel 1 by first pressing the CHANNEL 1 SELECT key and the following menu will appear on the display Arrows form the cursor and highlight one of...

Page 65: ...4 1 Input Connections The Model 931A can measure the frequency of AC voltages or currents connected only on Channel 1 Make connections in the same manner as for magnitude measurements see Section 3 2 2 for AC voltages and Section 3 2 3 for AC currents 3 5 4 2 Configuring the Channels Frequency measurement is permitted only on signals routed to measure ment Channel 1 Configure Channel 1 by first pr...

Page 66: ...ther Channel 1 or 2 to measure harmonics but on only one channel at a time 3 5 5 1 Input Connections Make connections for harmonic measurement in the same manner as for AC voltage or current magnitude measurements Since the Model 931A derives the harmonic value from the same inputs simply press the HARMONICS key to view them See Section 3 2 2 AC voltages and Section 3 2 3 AC currents for descripti...

Page 67: ...monic information highlighted by the cursor These values include the following The channel being measured The input configuration for the channel The harmonic number The harmonic amplitude as a percentage of fundamental amplitude The rms amplitude of the harmonic The phase angle of the harmonic relative to the fundamental The frequency of the harmonic The top line of text shows THD and K factor wh...

Page 68: ...ltage voltage to current or current to current in this manner For phase angle and or power quantity measurements route the voltage signal to Channel 1 and the current signal to Channel 2 Since the voltage in a power system is usually more stable and less distorted than the current the Model 931A uses Channel 1 as a reference for phase measurements Both a voltage and current input signal are requir...

Page 69: ...e number at the top of the display shows the phase angle of the signal routed to Channel 2 relative to that of Channel 1 It also shows the frequency of the signal at Channel 1 Dashes will appear for phase angle if signals of sufficient amplitude are not routed to both Channel 1 and Channel 2 For a more detailed description of Frequency Measurement see Sec tion 3 5 4 3 6 1 3 Phase Preference If the...

Page 70: ...d See Section 3 6 for input connection description Range Polarity Setting Resultant Setting for Ch 2 lagging Ch 1 Reading 180 negative 60 180 positive 60 0 360 negative 300 0 360 positive 60 Table 3 8 Phase Convention Figure 3 13 Phase Angle Example 3 6 2 Active Power Reactive Power The Model 931A can measure the active power rms watts and reactive power vars from the combination of an AC voltage ...

Page 71: ... to measure an AC voltage between inputs A and N Press ENTER to confirm the selection Press CHANNEL 2 SELECT to configure channel 2 current e g Ia Move the cursor to the desired measurement value and press ENTER to confirm the selection For example using the arrow keys move the cursor to Ia to measure an AC current at the A input terminals 3 6 2 2 Performing the Measurement Pressing POWER VARS wil...

Page 72: ...and current only using proprietary DSP algorithms Harmonics are ignored Dashes will appear in the display if insufficient signals are present during measurements performed in narrow band mode Narrow band results are computed in 3 5 and 3 6 3 5 ActivePower Vfund Ifund cos θ 3 6 ReactivePower Vfund Ifund sin θ 3 6 3 Apparent Power Power Factor The Model 931A can measure the apparent power volt amps ...

Page 73: ... to produce a display similar to the one shown below The large number at the top of the display shows the apparent power measured The lower number shows the power factor Also the display indicates whether the values are wide band or narrow band measurements Press SHIFT then BAND WIDE to change the measurement mode to wide band RMS including all frequencies up to 3 05 kHz Wide band apparent power i...

Page 74: ...RM key again to display both wave shapes simultaneously The Model 931A Waveform Display includes a text display showing the rms magnitudes for the two signals and the frequency of the signal at Channel 1 The following example shows a typical Waveform Display Signals are aligned so that the zero crossings of each channel appear at the left hand edge of the display 3 7 Timer Measurements The Model 9...

Page 75: ... using the arrow keys highlight the desired item and press ENTER to confirm the selection The following sections describe the individual selections from this menu 3 7 2 1 Select Timer Function Select Function from the Timer Configuration menu and press ENTER to view the following display Time A to B configures the timer circuitry to display the time elapsed between a valid trigger for the A input ...

Page 76: ...B input trigger periods are cumulative 3 7 2 2 Timer Display Choices To select whether time data is displayed in seconds or in cycles select Display Choice from the Timer CONFIG main menu and press ENTER For cycles the data may be based on 50 Hz 60 Hz or the fundamental frequency of the signal present at measurement Channel 1 Ch 1 Hz Select Display Choice from the Timer Configuration Menu to view ...

Page 77: ...ct Timer Trigger A Select Trigger A from the Timer Configuration Menu and press ENTER to view the following display This sub menu allows selection of the type of input to be used for the trigger for timer Channel A The following are descriptions of each of the choices DC Applied configures the timer input to trigger with a 3 volts DC or greater signal DC Removed configures the timer input to trigg...

Page 78: ...hold is approx 2 9 volts with a pull up impedance of approx 47 kilohm to a source voltage of approx 8 volts Contact Closed configures the timer input to recognize the closing of an electrical contact as a trigger event The threshold is approx 2 6 volts with a pull up impedance of approx 47 kilohm to a source voltage of approx 8 volts 3 7 2 5 Select Timer Trigger B Press the Timer CONFIG key and se...

Page 79: ...witches the timer from the Stopped to Standby The Model 931A displays the timer state below the word Timer A blank status indicator signifies the instrument is in Standby 3 7 3 2 Time Measurements Time Measurement Timer functions return a time value with finite start and stop points Measurements falling in this category are Time A to B Time A for X Counts Time Width of A During these modes of oper...

Page 80: ...nsducer input values Transducer output may be set to either Measured Quantity Percent Full Scale or Percent Error while simultaneously displaying the transducer inputs This provides a look at the input and output quantities for better control during the measurement and fewer chances for measurement or setup errors The Model 931A Transducer input uses accurate optically isolated input sections to a...

Page 81: ...transducer input and route a voltage or current of the same frequency to Channel 1 Do not select the same input for both Channel 1 and Channel 2 See Figure 3 14 1Ph 3Wire 2E sets the Model 931A to measure values in a circuit having two hot wires and a neutral wire Commonly referred to as Split Phase this type of circuit is generally used to supply residential service This particular configuration ...

Page 82: ...the following three combinations voltage A to N with current A voltage B to N with current B and voltage C to N with current C Three phase display and percent error calculations use the average for V A θ phase and PF and the total for W VAR and VA 3 8 1 2 Input Type Select Input Type from the Transducer Configuration menu and press ENTER to view the following sub menu Volts sets the Model 931A to ...

Page 83: ...play shows average current See Section 3 2 3 for a description of AC current measurements Frequency sets the Model 931A to measure frequency at prede fined channel 1 for comparison to a frequency transducer The displayed frequency actually represents the instantaneous value which is updated with each measurement cycle See Section 3 5 4 for a description of frequency measurements Vars sets the Mode...

Page 84: ...se output ranges when the transducer outputs are connected to the transducer terminals on the front panel Within the ranges shown the Model 931A accepts either voltage or current signals Refer to Section 3 8 for details on connecting transducer inputs and Section 3 3 3 for a description on data entry Custom V allows the user to enter a voltage range within the limits of 0 to 10 volts DC Custom mA ...

Page 85: ...ducer under test i e volts or milliamperes Percent Full Scale displays the measured value at the output of the transducer under test as a percentage of full scale Full scale is defined by the lower and the upper limit of the selected output range Does not apply for Custom Pulse Percent Error displays the measured error of the transducer based on the measured input and output quantities To properly...

Page 86: ...ts to use for testing of each type of transducer except 1 Phase 2 Wire These definitions are described in the Transducer Mode Selection menu shown in Section 3 8 1 1 Figures 3 14 through 3 17 illustrate various examples of connections for transducer testing Use any of the voltage and current inputs to measure single phase two wire transducers since they do not require sequential measurements Use c...

Page 87: ...tion does not require sequential measurements within the Model 931A Therefore any of the 3 voltage inputs and any of the 3 current inputs may be used Refer to text for more details Figure 3 14 1 Phase 2 Wire 1 Element Transducer Test 71 ...

Page 88: ...UENCY POWER VARS VA PF HARMONICS WAVEFORM CHANNEL 1 SELECT CHANNEL 2 SELECT MEASURE HOLD CH2 RANGE MIN MAX TRANSDUCER MENU LOG DATA PRINT LAST SETUP CH1 CH2 ON OFF FUSE 1AF 250V 85 264 Vac 47 440 Hz 110 250 Vdc RS 232 GROUND BEFORE USE A B C N 750 Vrms 1000 Vdc MAX 20 Arms MAX 10Vdc MAX 100mAdc MAX A B C DISPLAY CONFIG ARM RESET A B 300V MAX L1 L2 L1 L2 N N Iout LOAD SOURCE I1 I2 V1 V2 Figure 3 15...

Page 89: ...T CHANNEL 2 SELECT MEASURE HOLD CH2 RANGE MIN MAX TRANSDUCER MENU LOG DATA PRINT LAST SETUP CH1 CH2 ON OFF FUSE 1AF 250V 85 264 Vac 47 440 Hz 110 250 Vdc RS 232 GROUND BEFORE USE A B C N 750 Vrms 1000 Vdc MAX 20 Arms MAX 10Vdc MAX 100mAdc MAX A B C A N C C A N B B DISPLAY CONFIG ARM RESET A B 300V MAX Iout LOAD SOURCE I1 V1 V3 I2 I3 NOTES In 3 Phase 4 Wire 2 5 Element Mode the Model 931A voltage i...

Page 90: ...Iout I1 V1 V2 V3 I2 I3 Figure 3 17 3 Phase 4 Wire 3 Element Transducer Test 74 ...

Page 91: ...er represents the transducer output Display configuration determines whether measurement results are pre sented as a measured value or as a percent of full scale Sections 3 8 1 5 and 3 8 1 6 describe the Display Modes Additionally the Model 931A can present the lower number as a percentage of error in the transducer Percentage error is determined by comparing the ratio of the input and output valu...

Page 92: ...rtains to a 3 phase power transducer illustrated in Figure 3 18 Make these selections as follows as shown in the screen above 1 Input Mode select the Phase number of Wires and Elements e g 3P 4W 3E 2 Input Type select Volts Phase Power Volt Amps Amps Frequency Vars or Power Factor e g Power 3 Input Range select the transducer range being tested e g 0 1500 4 Output Range this selects the Custom Pul...

Page 93: ...SCAPE to return to the main menu If initially setting up a transducer custom pulse test proceed to the section on Timer Configuration below 3 8 5 4 Configuring in the Timer Menu Press the Timer CONFIG key to access the Timer Menu A sample menu is shown below Only two selections under Timer Function apply to the Custom Pulse feature Time A For X Counts and Rate of A Make the Timer Configuration sel...

Page 94: ... The best selection for contact closures 1 second is Time A For X Counts This function allows the Model 931A to measure transducers with contact outputs that are relatively slow in the range of seconds between pulses Typical devices that fit into this category could be transducers 1 Select Function in the Timer Configuration Menu and press ENTER 2 Select Time A For X Counts in the Select Timer Fun...

Page 95: ...n the Timer Configuration Menu Remember that Trigger B and Debounce B are not used in Custom Pulse transducer measurement functions 1 Press the Timer CONFIG key to access the Timer Configuration Menu With the cursor select Function and press ENTER to access the Timer Function menu 2 In the Timer Function menu select Rate of A and press ENTER 3 The Rate of A Function also continuously updates the t...

Page 96: ...est 3 8 6 1 For Contact Closures 1 second Use Time A For X Counts After setting up the test and configuring the Model 931A apply the input power source to the transducer and Model 931A Refer to Figure 3 18 Press the TRANSDUCER key to view the standard measurement screen Initially the Model 931A display will appear similar to the screen below 1 Allow a few seconds for the Transducer Input value to ...

Page 97: ...figure new test parameters press either SHIFT then CON FIG transducer or CONFIG timer to change the measurement settings After re configuring the test parameters press the TRANS DUCER key and the Model 931A is ready for another test To start the next test press the ARM RESET key twice 3 8 6 2 For Contact Closures 1 second After setting up the test and configuring the Model 931A apply the input pow...

Page 98: ...eplace the date and time information The screen below illustrates the Model 931A measuring a transducer using Rate of A 3 Using the Rate of A Function the Model 931A should continually update the measurement values The Model 931A also cycles between each measured phase indicated in the lower left corner of the display 4 The Transducer Input value indicates the total input in this case three phase ...

Page 99: ... I1 V1 V2 V3 I2 I3 Output Contacts or Pulse TRANSDUCER Figure 3 18 3 Phase 4 Wire 3 Element Custom Pulse Transducer Test 83 ...

Page 100: ...sion of the CH1 CH2 function can be found in Section 3 3 1 17 Example measure the ratio of a PT by performing the following steps 1 Use Channel 1 to configure the Model 931A to measure the voltage at the input of the PT 2 Use Channel 2 to configure the Model 931A to measure the output of the PT 3 Apply the operating voltage to the input of the PT and press the CH1 CH2 key 4 The resultant display s...

Page 101: ...del 931A captures a data record it displays a momentary message in the lower right hand corner The message confirms that the data was saved and shows the assigned record number Because any of the four different types of data may be recorded at any time the total number of records saved will vary 3 10 2 Reviewing Data Review stored data records by using the second function of the LOG DATA key Press...

Page 102: ... port Refer to Sections 2 6 4 3 7 and Appendix A for information on using the RS 232 port Print or export data at the time the measurement is performed or store it for later printing or exporting using the LOG DATA key Most printed or exported data records are stamped with the date and time according to the real time clock in the Model 931A Each data record also includes a record number referred t...

Page 103: ... the display contents to a bitmap file BMP Bitmap files can be imported into graphics and word processing programs and is useful for graphics displays of harmonics or waveforms Bitmap data uses 2110 bytes per captured screen The bitmap export feature utilizes the XMODEM file transfer protocol with CRC which allows the file to be captured using most common communications programs e g Procomm Window...

Page 104: ...munication and begin the transfer 3 11 5 Spreadsheet Use this mode to import data directly into spreadsheet programs Data is comma and quote delimited commas separate all data fields number and text with text enclosed in quotes The type of exported data depends on which operating mode the Model 931A is set for at the time the PRINT key was pressed Firmware outputs all spreadsheet data as ASCII tex...

Page 105: ...of 1 corresponds to the time of day and is the standard format for time in spreadsheet applications This number is determined by the formula n S 86400 where S number of seconds elapsed since midnight Min Max Aver age Normal Denotes whether the data corresponds to the minimum recorded values maximum recorded values average recorded values or normal mea surement Ch1 Select Describes the input config...

Page 106: ...el 931A exports 3 phase data when executing the print operation This occurs in one of the 3 phase tabular display operating modes The 3 phase data is exported with the following format log data date time min max normal 3 phase mode ABC CBA V A phase frequency power vars VA PF Log Data A number assigned to the data record If the data was stored prior to print export this number will correspond to t...

Page 107: ...at the time of export The choices are 1 phase 3 wire 2 element 3 phase 3 wire 2 element 3 phase 3 wire 3 element 3 phase 4 wire 3 element 3 phase 4 wire 2 5 element ABC CBA Indicates phase sequence V Average voltage for all phases A Average current for all phases Phase Average Phase angle between current and volt age for all phases Frequency The frequency of the measured signals Power The total ac...

Page 108: ...ent Phase C Phase phase angle Power C Phase power VARS C Phase reactive power VA C Phase apparent power PF C Phase power factor PF Lead Lag 3 11 5 3 Timer Data The Model 931A exports timer data when executing the print operation This occurs while performing measurements or reviewing stored data in the timer mode of operation Timer data is exported with the following format log data date time min m...

Page 109: ...t applications This number is determined by the formula N S 86400 where S number of seconds elapsed since midnight Min Max Aver age Normal Denotes whether the data corresponds to the minimum recorded values maximum recorded values average recorded values or normal mea surement Function Describes the type of Timer measurement For details on the different types of timer measure ments refer to Sectio...

Page 110: ...Date An integer corresponding to the date which is the standard format for dates in spreadsheet applications The integer for the date is deter mined from the following 1 1 1600 109 571 12 30 1899 0 1 1 95 34700 12 31 3199 474 816 Time A decimal fraction of 1 corresponding to the time of day which is the standard format for time in spreadsheet applications This number is determined by the formula N...

Page 111: ...0 phaseC Log Data A number assigned to the data record If the data was stored prior to print export this number will correspond to the record number assigned when stored If the data is printed or exported directly this number will always be zero Date An integer corresponding to the date which is the standard format for dates in spreadsheet applications The integer for the date is deter mined from ...

Page 112: ... measurements in the waveform display mode or reviewing stored data while in that mode Waveform data is tabular format and similar to harmonic data It consists of 240 records which correspond to points on the waveforms for measurement channels 1 and 2 Following is the format for waveform data log data date time channel 1 channel 2C channel 1 channel 2C channel 1 channel 2C C C channel 1 channel 2C...

Page 113: ...number is determined by the formula N S 86400 where S number of seconds elapsed since midnight Channel 1 Data point for Channel 1 Waveform Channel 2 Data point for Channel 2 Waveform 3 11 6 Initiating Printing Exporting To print or export data directly press the PRINT key during the measurement see Section 3 11 4 for Bitmap transfers Ensure that all RS 232C connections and parameters are properly ...

Page 114: ...98 ...

Page 115: ...0 Vrms under range to 200 mV 2 1000 Vdc under range to 300 mV Impedance 1 megohm Leakage 3 5 mA per IEC 348 and UL 1244 4 1 2 Current Inputs Three A B and C Input Range 0 04 20 Arms under range to 1 mA Burden 0 01 Ω maximum Isolation 1000 Vpeak transformer coupled 4 1 3 Transducer Inputs Two one for voltage and one for current common return terminal 99 ...

Page 116: ... 9 Volts Threshold Contact closed 2 6 Volts Source Impedance 25 kΩ for dry contact 4 2 Measurements 4 2 1 Voltage and Current Method Wideband True RMS 3 kHz BW Narrowband Fundamental Magnitude Accuracy 0 05 of reading Under range 1 of reading typical at 0 3 mArms DC Voltage 0 1 of reading 25 mV typical 4 2 2 Phase Angle Input Channel 1 to Channel 2 Range 0 360 or 180 Accuracy 0 05 Under range 1 de...

Page 117: ...1 to 9999 9 seconds 0 01 to 999999 cycles Accuracy 0 005 of reading 1 digit Trigger Error for AC Trig 1 millisecond maximum 0 15 milliseconds 120 Vrms 4 2 5 Transducer Accuracy 0 05 of reading 0 01 of range 4 2 6 Harmonics Input Channel 1 or Channel 2 Range 2nd to 50th harmonic 50 Hz or 60 Hz funda mental Accuracy 0 01 THD 5 of reading 4 2 7 Power Quantities Range 0 99999 MVA 99999 MW 99999 MVAR 1...

Page 118: ...s Time and date tagged 4 3 3 Display Type Supertwist Liquid Crystal Resolution 240 h by 64 v pixels Dimensions 134mm h by 31mm v Backlight Cold cathode fluorescet lamp Auto Mode Shutdown 10 seconds after last keystroke 4 3 4 Keypad Main Keyboard 18 multi function keys Timer Control 3 keys 4 3 5 Environment Operating 10 to 50 C Storage 40 to 75 C Humidity Non condensing Size 205 x 305 x 225 mm 8 x ...

Page 119: ...Auto Shutdown 10 minutes with no activity or input 4 3 7 Serial Port Port Type RS 232C Baud Rate 1200 115200 Data Bits 7 or 8 Stop Bits 1 or 2 Parity None even or odd Flow Control XON XOFF or hardware Pin Locations 1 N C 2 RXD 3 TXD 4 DTR 10k pull up output 5 Signal Common 6 N C 7 RTS driver output high 8 CTS hardware flow control input 9 N C Cable type Null modem for PC compatible Isolation 300 V...

Page 120: ...104 ...

Page 121: ...esired measurement prior to issuing a data request command Verify that the following items are setup properly Channel 1 and 2 Input Signal Use Channel 1 if only one signal is to be measured Set Channel 1 to measure AC voltage and Channel 2 to measure AC current if measuring power quantities power VARS VA or power factor Measurement Bandwidth To measure fundamental frequencies only select the narro...

Page 122: ...m Example Result 6 1CHS Select channel 1 to measure Van LOG Stores a record of the current measurement channel in standard or extended memory 3RLD Overwrites the display with record number 3 stored in standard memory 3 2HMA Returns via the serial port the third har monic magnitude measured on channel 2 0 1 1 0 0 0TCF Sets the Timer configuration as follows Display in seconds Function to Time A to ...

Page 123: ...light remains on for approximately 20 seconds after the last keystroke A 3 3 Channel Calibrate CCH Command ch ac dc range gain ph off s r CCH Sets or returns the calibration constants for Channel 1 and Channel 2 Each channel has a set of calibration constants for each range Action 1 Select Channel 1 2 Select Channel 2 ac dc 0 DC 1 AC range 0 8 see SRG command below gain Corrected gain uncorrected ...

Page 124: ...of Channel 1 divided by Channel 2 Depending on the input signals selected the display units for magnitude will be ohms mhos or p u A 3 5 Channel Input Select CHS Command in ch CHS Specifies the input signal for the selected channel as follows AC AC DC in Config in Config in Config 0 Vab 11 Vcs 15 Vab 1 Vbc 12 Ia 16 Vbc 2 Vca 13 Ib 17 Vca 3 Vac 14 Ic 18 Vac 4 Vcb 27 Vb Ch1 only 19 Vcb 5 Vba 28 In C...

Page 125: ...se uncorrected phase ph off freq Offset ph off 1000 DC s r Action 0 Writes calibration to memory 1 Returns stored calibration value Return format gain cr lf phase offset cr lf Numbers are returned in fixed point format with 5 digits plus a decimal point A 3 7 Transducer Configuration COT Command m int infs inll dco ofs oll oll di do COT Configures the parameters necessary for transducer calibratio...

Page 126: ...ror A 3 8 Daylight Saving Time Set DAY Command DAY Sets the daylight saving time mode for the real time clock Designation 0 Daylight saving time OFF 1 Daylight saving time ON adds one hour to the standard time 2 AUTO daylight saving time automatically adjusts the time for USA standard daylight saving time 2 00 AM on the first Sunday in April to 2 00 AM on the last Sunday in October A 3 9 Display D...

Page 127: ...or painting programs A 3 11 Store Calibration Data in EEPROM EEP Command mmddyyEEP Stores Calibration Data currently residing in RAM to EEPROM using a Hamming Code Sets Calibration Date to the current date MM DD YY is the current date A 3 12 DSP Frequency Calibrate FRD Command c s r FRD Sets or returns the Calibration Constant to correct the DSP frequency 1 c 1 000 000 multiplies the frequency mea...

Page 128: ...s Display HAR Command harm ch HAR Displays the selected harmonic with others for the selected channel Shows magnitude phase and frequency data for the harmonic number specified as harm Ch To select 1 Channel 1 2 Channel 2 A 3 16 Harmonic Magnitude Return HMA Command harm ch HMA Returns individual harmonic magnitudes for the selected channel Set the unit to measure harmonics on the selected channel...

Page 129: ...Data LOG Command LOG Stores the current measurement data using current date time and instrument settings in the next available location of the non volatile data memory Stores all data with current data type standard data standard with harmonic data or standard with harmonic and waveform data Recall data using the review logged data RLD command A 3 20 Last Setup LSU Command LSU Restores the instrum...

Page 130: ...1 Measure Hold ON Stops the measurement process holding all parameters at their current values Select the desired display function prior to issuing this command and observe the corresponding values A 3 23 MIN MAX Display MMN Command MMN Displays the minimum maximum average or present values for each parameter Updates minimum maximum and average continuously Use the RST command to restart the accum...

Page 131: ... use Channel 1 for the voltage and Channel 2 for the current A 3 27 Power Vars Display P V Command P V Displays the active and reactive power of the signals on Channels 1 and 2 Set Channel 1 to measure AC voltage and Channel 2 AC current To select 0 or absent Power Vars 1 Watt hours Var hours A 3 28 Power Factor Return PFA Command PFA Returns the power factor of Channel 1 and 2 together Channel 1 ...

Page 132: ...hase Return PHS Command PHS Returns the phase angle of Channel 2 relative to Channel 1 Use the SPH command to set the phase preference 0 360 or 180 degrees leading or lagging In 3 phase mode returns the average of the individual phase measurements Response Numeric ASCII string A 3 31 Power Return PWR Command PWR Returns the active power of Channel 1 and 2 together Channel 1 must be set to measure ...

Page 133: ...RLD to clear all logged data When issuing this command the specified record is written to the Model 931A display overwriting current measurement data and placing the Model 931A in Measurement Hold Mode Use 0MHD to release Measurement Hold Mode and resume measurement See appendix B for use of this command with the Extended Memory Option A 3 34 Range Hold Release RRH Command ch RRH Releases range ho...

Page 134: ...r SER Command serial s r SER Sets or returns instrument Serial Number See Note 1 on page 105 Serial s r ASCII number 5 digits 0 To enter serial number 1 To return serial number A 3 38 Flash Log SLO Command 1 2 3 4 5 6SLO Sets the Flash Log operation See Appendix B for use of this command with the Extended Memory Option 1 If no numbers present it starts a new file 2 If 1 number present 0 disable fl...

Page 135: ...individual scale factors ON 2 Enable PT CT ratios A 3 40 DSP Speed SPD Command 1 s r SPD 1 To select 0 Slow mode 1 Fast mode s r 0 To set speed 1 To return speed A 3 41 Phase Preference Set SPH Command SPH Specify the format for phase display Phase Format 0 180 degrees leading negative display means Channel 2 lagging Channel 1 1 180 degrees lagging positive display means Channel 2 lagging Channel ...

Page 136: ...7 8 5 20 3 12 28 0 32 0 75 17 40 4 24 56 0 64 1 49 34 80 5 48 112 1 28 2 98 68 160 6 96 224 2 56 5 97 135 8 320 7 192 448 5 12 11 9 271 5 640 8 384 750 10 24 20 0 543 1000 ch To Select 1 Channel 1 2 Channel 2 A 3 43 Scale Factors Set or Return SSC Command in m p s r SSC Set or return calibration factors to be applied to each input function such as for CT or PT corrections Scale factors consist of ...

Page 137: ...he present instrument setup in Setup Location 1 through 6 A 3 45 Setup Recall SUP Command SUP Recalls the instrument setup as stored with Store Setup SST 1 through 6 A 3 46 Timer Arm TAM Command TAM Arms the Timer For proper operation the Timer must be armed prior to a valid trigger condition If there is a non zero number on the Timer display the TAM command will set it to zero A 3 47 Time Return ...

Page 138: ...les 50Hz 1 Time A for X Counts 2 Cycles 60Hz 2 Time width of A 3 Cycles Ch1 Hz 3 Frequency of A 4 Count A Events 5 Count A events gated by B h Hold mode on stop 0 Disable 1 Enable at A Trigger bt B Trigger 0 DC Applied 0 DC Applied 1 DC Removed 1 DC Removed 2 AC Applied 2 AC Applied 3 AC Removed 3 AC Removed 4 Contact Open 4 Contact Open 5 Contact Closed 5 Contact Closed s r Set or Return Value 0 ...

Page 139: ...Response Numeric ASCII string A 3 53 Timer Reset TRS Command TRS Resets the Timer to prepare for a new timing cycle NOTE Arm the Timer before starting the timing cycle either via front panel ARM RESET key or the RS 232C TAM command A 3 54 Timer Stop TSP Command TSP Stops the Timer A 3 55 Timer Start TST Command TST Activates the Timer Arm the Timer prior to starting a timing cycle either via front...

Page 140: ...command Response Numeric ASCII string A 3 59 VARS Return VAR Command VAR Returns the reactive power of Channel 1 and 2 together Set Channel 1 to measure AC voltage and Channel 2 AC current Returns total reactive power in 3 Phase Mode Replaces Power Quantities with Energy Readings when a 1 precedes the VAR command Response Numeric ASCII string A 3 60 Version Return VER Command VER Returns the firmw...

Page 141: ...WIB Command WIB Changes the measurement mode for amplitude and power quantities to wide band including all harmonics up to 3 05 kHz A 3 63 Transducer Input Display XDI Command XDI Returns the value for the Transducer input as it appears on the main display A 3 64 Transducer Output Display XDO Command XDO Returns the value for the Transducer output as it appears on the main display 125 ...

Page 142: ...126 ...

Page 143: ...y of 0 1 and 0 1 Mounts in 931A transit case includes mounting bracket and hardware P N AS0036000 B 1 1 Specifications Range 0 8 400 Arms Burden 14 mohms Accuracy Amplitude 0 1 of reading Phase 0 1 B 1 2 Input Connections Connect a high current source as follows 1 Slip the transformer output spade lugs into one set of the Model 931A current input binding posts A B or C and tighten securely 2 Conne...

Page 144: ...D0049900A Fastener Knob 2 HP0014200A B 2 2 Required Tools The only tool required for installation of the bail is a 2 5mm Allen wrench B 2 3 Procedure NOTE Perform the following steps to attach a mounting bracket to one side of the case Repeat for the opposite side see Figure B 1 1 Remove the four existing M5 screws that hold the instrument to the outer case 2 Assemble Handle Bail onto mounting bra...

Page 145: ...is equipped with standard memory however the record structure is more elaborate Additionally users can customize recorded data with the Custom function Note Do not attempt to remove or modify the memory card as it is permanently mounted within the Model 931A Regardless of the power On Off state of the analyzer the extended memory module retains the stored data and instrument configurations Only by...

Page 146: ...ta consists of a complete set of data parameters whereas the custom data function allows the user to select the individual parameters to be recorded changing the record structure The custom data feature can be used to maximize the number of data records stored in extended memory B 3 1 1 Normal Each record stored as normal data contains enough information to com pletely restore the Model 931A to it...

Page 147: ...hen pressing the log data key after changing the display B 3 1 2 Custom Users may program custom record structures from the front panel or through the RS232 port Custom data records allow the operator to store only the parameters of interest maximizing the number of data records stored in extended memory Defined by a 32 bit word each bit of the word defining the record corresponds to a particular ...

Page 148: ...2 25 33 544 432 3Ph Sequence 48 26 67 108 864 Timer 10 27 134 217 728 Transducer 35 28 268 435 456 Harmonic 784 29 536 870 912 Ch1 Waveform 240 30 1 073 741 824 Ch2 Waveform 240 31 2 147 483 648 Not Used Table B 1 Custom Data Table B 3 2 Computing the Number of Files and Records With the 16 megabyte extended memory option installed the Model 931A is limited to a maximum of 20 files Beyond that it ...

Page 149: ... desired data type When ready to begin data collection arm the timer by pressing the front panel ARM RESET key or issue the RS232 TAM command Data will be logged each time a valid Timer A trigger is received Data logging will not occur faster than once per second Triggers received faster than once per second will be ignored Press the ARM RESET key or issue the TRS command to suspend data logging T...

Page 150: ...he parameter as each parameter is displayed Press the ENTER key to move to the next parameter and the ESCAPE key to quit the selection process Along with the name of each data parameter is the number of bytes it requires each time it is logged Table B 1 contains a list of the available custom data parameters Time is shown as an optional parameter however it is automatically stored with each data r...

Page 151: ...ge indicating the file number i e Hold Log 2 Press the LOG DATA key to proceed through the logged records of the selected file The record number will be displayed in square brackets The arrow keys are used to control the record retrieval direction and increment number Press SHIFT and the appropriate arrow key to change viewing conditions Up arrow Review records in ascending order Down arrow Review...

Page 152: ... be started See SLO above 0 0 0SLO Configures data logging for normal data with the store trigger set for the front panel LOG key or the RS232 LOG command 0 0 33281SLO Configures data logging for custom data with the store trigger set for the front panel LOG key or the RS232 LOG command The custom data includes time Channel 1 rms and Channel 2 rms 1 0 0SLO Configures data logging for normal data w...

Page 153: ... to compute the custom data word for logging time and channels 1 and 2 magnitude data Parameter Decimal weight Time 1 Channel 1 rms 512 Channel 2 rms 32768 Custom configuration value 33281 B 3 7 Review of Logged Data 1 2RLD selects a log record for review or removal If 1 and 2 are absent A list of stored records is returned If only 1 number is present 0 All records are cleared including flash memo...

Page 154: ...he header data for the third file The unit will be configured to the state it was in when the file was created The unit is placed in measure hold mode To return to normal operation issue the 0MHD command or press the MEASURE HOLD key 0 4RLD Erases logged data file number four and decrements the file number of all files 5 and greater by one 3 12RLD Recalls the data stored in the twelfth record of t...

Page 155: ...ated and Conducted Emissions Standard EN50082 1 Generic Immunity Part 1 Referenced Residential Commercial and Light Industrial Environments EN61010 1 Safety requirements of Electrical Equipment for Measurement Control and Laboratory Use Signed Signatory Bruce H Roeder This certificate declares that the described equipment conforms to the applicable requirements of the directives on Electromagnetic...

Page 156: ...131 133 134 138 backlight battery life 44 function 24 type 102 battery charging 10 extending life 10 grounding 13 grounding safety 44 life 103 life with backlight 44 line power 10 low indicator 10 power 1 RAM 102 cable null modem 2 9 CE Mark Certification 139 Channel 1 range 37 select 22 Channel 2 range 23 37 select 22 channels measurement 5 commands serial see RS 232C commands connection diagrams...

Page 157: ...nection 9 setup 86 extended memory 129 SLO examples 135 fast mode accuracy 8 FFT 7 21 51 frequency range 6 front panel connections 13 display 44 drawing 4 keys 15 ground chassis current input isolation 3 current inputs isolated 46 grounding safety 13 44 handle bail 128 harmonics bandwidth 21 determining 21 selecting 21 hold mode 23 input connections AC current 46 active reactive power 54 apparent ...

Page 158: ...row 42 Scale 39 secondary functions 26 Setup 1 6 27 Shift 26 Store Setup 39 timer control functions 42 Transducer 24 Up Arrow 42 VA PF 18 Volts Amps 16 Waveform 21 Wide Band 27 logging data 84 main functions 15 Harmonics 21 Phase Frequency 16 Power Vars 17 VA PF 18 Volt Amps 16 Waveform 21 maximum ratings 3 measure AC Current 46 AC Voltage 44 Active Reactive Power 54 Apparent Power 56 Combined fun...

Page 159: ...tion 105 RS 232C commands BAT charge status 107 BLT backlight set 107 CCH channel cal 107 CCR ch1 ch2 ratio 108 CHS channel select 108 CIN calibrate input 109 COT Xdcr config 109 DAY set DST 110 DDA display dump 110 DDB bmp data dump 111 EEP store cal data 111 FRD DSP freq return 111 FRQ freq return 111 FTM timer cal 112 HAR harmonics displ 112 HMA harm mag 112 HPH harm phase 113 KIL power down 11...

Page 160: ...annel 1 22 Channel 2 22 Min Max Average 24 shut down Auto 24 KIL command 113 sign on message 11 specifications precision CT 127 specifications general 102 current 99 display 102 environment 102 input power 103 keypad 102 measurement BW 102 memory 102 serial port 103 specifications input 99 timer 100 transducer 99 voltage 99 specifications measurement 100 frequency 101 harmonics 101 phase angle 100...

Page 161: ...necting the inputs 70 connecting the outputs 75 custom pulse 75 choosing a test method 75 display output 69 displaying input 68 input mode 65 input range 67 input type 66 inputs 15 key 24 measurement units 5 output range 68 performing the measurement 75 testing 64 transducer test connection 1P2W1E 71 1P3W2E 72 3P4W2 5E 73 3P4W3E 74 3P4W3E custom pulse 83 user interface 8 version manual v viewing s...

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