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8. KEYBOARD AND DISPLAY

GEK-106168E

DBF Breaker Failure Protection

43

8.2. SETTINGS GROUP (SET KEY)

This group allows to see and modify the DBF settings. It is accessed by pressing the SET key when the DBF is in
steady state. When the SET key is pressed the following message appears on the screen:

VIEW SETTINGS

PROTECTION

When the UP/DOWN arrows are pressed the message changes to:

MODIFY SETTINGS

PROTECTION

And the last UP/DOWN action gives:

MODIFY COUNTERS

PROTECTION

For the above windows, the menu tree is shown in the following tables. Note that to go down a level in the tree the
ENT key must be pressed, and the CLR key to go up

Level 1

Level 2

Level 3

Level 4

RELAY STATUS

In/Out of service

IDENTIFICAT

20 characters

FREQUENCY

50 – 60 Hz

PHASE CT RATIO

1-4000

GENERAL SETTINGS

GROUND CT RATIO

1-4000

BREAKER NUMBER

4 digits

KI2t OP. MODE

Fixed / Measuring

KI2t INT TIME

0.03 - 0.25 s

BREAKER SETTINGS

KI2t LIMIT

1 – 999999 kA2s

ACTIVE

TABLE SET

ACTIVE TABLE

1 –3

PREFAULT CYCLES

0-4

PICKUP

ENABLE/DISABLE

1

st

STAGE TRIP

ENABLE/DISABLE

2

nd

STAGE TRIP

ENABLE/DISABLE

INTERNAL ARC

ENABLE/DISABLE

50BF A TRIP

ENABLE/DISABLE

50BF B TRIP

ENABLE/DISABLE

50BF C TRIP

ENABLE/DISABLE

50BF 3P TRIP

ENABLE/DISABLE

EXTERNAL TRIGGER

ENABLE/DISABLE

COMM. TRIGGER

ENABLE/DISABLE

HI-SET A PICKUP

ENABLE/DISABLE

HI-SET B PICKUP

ENABLE/DISABLE

HI-SET C PICKUP

ENABLE/DISABLE

50BF A INIT

ENABLE/DISABLE

50BF B INIT

ENABLE/DISABLE

50BF C INIT

ENABLE/DISABLE

LO-SET A PICKUP

ENABLE/DISABLE

LO-SET B PICKUP

ENABLE/DISABLE

LO-SET C PICKUP

ENABLE/DISABLE

3 POLE 50BF INIT

ENABLE/DISABLE

NEUTRAL PICKUP

ENABLE/DISABLE

ARC A PICKUP

ENABLE/DISABLE

VIEW

PRO

T

ECT

IO

N

SET

T

ING

S

O

S

CILLO

S

M

ASK

ARC B PICKUP

ENABLE/DISABLE

ARC C PICKUP

ENABLE/DISABLE

Summary of Contents for DBF

Page 1: ...ctions Instructions Instructions Instructions GEK 106168E GEK 106168E GEK 106168E GEK 106168E Digital Breaker Failure Protection Digital Breaker Failure Protection Digital Breaker Failure Protection Digital Breaker Failure Protection ...

Page 2: ... 28 9 1 200 17 21 7 217 176 2 7 35 6 17 0 18 1 86 23 2 7 6 3 72 7 5 7 23 2 7 3 5 28 9 281 7 352 0 72 7 180 5 1 1 7 48 67 21 5 2 33 72 62 9 285 28 76 1 7 1 28 25 3 1 86 03529 7 6 0 18 RPSDQ 1DPH GGUHVV 3KRQH D PDLO HVFULSWLRQ RI RXU TXHVWLRQ RU VXJJHVWLRQ 0DQXDO FRGH ...

Page 3: ......

Page 4: ...uts and Outputs 13 2 5 MAN MACHINE INTERFACE HMI 15 2 6 REMOTE COMMUNICATIONS 16 3 SETTINGS 17 4 TECHNICAL CHARACTERISTICS 21 4 1 MODEL LIST 21 4 1 1 Special Models 21 4 2 TECHNICAL CHARACTERISTICS 22 5 HARDWARE DESCRIPTION 25 5 1 PHYSICAL DESCRIPTION 25 5 1 1 Case 25 5 1 2 Electrical Connections 25 5 1 3 Internal Construction 25 5 2 OPERATING THEORY 27 5 2 1 Magnetic Module 27 5 2 2 CPU Board 27 ...

Page 5: ...ent 37 6 10 2 Timing Measurement 37 7 INSTALLATION AND MAINTENANCE 39 7 1 INSTALLATION 39 7 2 CONNECTION TO GROUND AND DISTURBANCES SUPPRESSION 39 7 3 MAINTENANCE 39 8 KEYBOARD AND DISPLAY 41 8 1 MENU TREE 42 8 2 SETTINGS GROUP SET KEY 43 8 3 INFORMATION GROUP INF KEY 46 8 4 CONTROL GROUP ACT KEY 47 8 5 SINGLE KEY MENU 48 8 6 CONFIGURATION MENU 49 FIGURES 51 ...

Page 6: ...ic 189C4114 Sheet 2 Figure 2 External Connections 189C4114 Sheet 1 Figure 3 Front View 226B7412 Sheet 9 Figure 4 Rear View 226B7412 Sheet 10 Figure 5 Dimensions Diagram 226B6086 sheet 10 Figure 6 Panel drilling 226B6086H10 Figure 7 RS232 Connection DBF relay to PC Figure 8 RS232 Connection DBF relay to MODEM ...

Page 7: ...LIST OF FIGURES iv DBF Breaker Failure Protection GEK 106168E ...

Page 8: ...the relay The system provides the following functions a Protection Low current level breaker failure protection following a single or three phases initiation with up to two time delayed steps High current level breaker failure protection following a two three selectable by setting phases initiation No current breaker failure protection following a two three selectable by setting phases initiation ...

Page 9: ...ocated on the rear Human machine interface HMI consisting of 20 keys keypad and alphanumerical LCD 16 characters x 2 lines Windows based GE INTRO configuration software for inputs outputs LEDs configuration and GE LOCAL communications software for relay monitoring settings change stored data retrieve etc Both are part of the GE NESIS software package General Electric Network Substation Integrated ...

Page 10: ...ing on settings one or two time delayed tripping steps Use 50BF_1P setting permitted Not permitted and number of output stages N of Output Stages setting to enable this function and to set the number of steps Timers T1 and T2nd control the timing of the first and second step respectively 1_Phase Timer T1 and 2nd Stage Timer settings If the tripping signal is three pole type digital input E7 E8 for...

Page 11: ...nd some amount of current is present in any phase There are two settings available for this function Internal Arc Pickup to set the current threshold and Internal Arc Timer to coordinate the operation time of the unit with the time it takes for the breaker and auxiliary elements to open If the circuit breaker is open then the 52 b contacts will energize the digital inputs corresponding to the circ...

Page 12: ...d to blink or to be steady The internal events must be previously defined using the internal signals of the relay It is possible to use AND OR and NOT logic gates to define these events The available internal signals are listed in the following table The TARGET RESET button allows testing all target lamps if it is pushed for a short time lighting up all of them or resets the sealed in targets if i...

Page 13: ...urrent detector ph B 3 9 Lo Set C Pickup Output of Lo Set current detector ph C 3 10 50BF 3 Phase Initiate CC7 Dig Input ON default configuration 3 11 50BF Neutral Initiate Output of Neutral current detector 3 12 Internal Arc A Pickup Output of AND 16 in figure 1 3 13 Internal Arc B Pickup Output of AND 17 in figure 1 3 14 Internal Arc C Pickup Output of AND 18 in figure 1 3 15 4 0 Pickup Any BF s...

Page 14: ...cumulated I2t above limit for Phase A 6 12 52 B Maintenance Alarm Accumulated I2t above limit for Phase B 6 13 52 C Maintenance Alarm Accumulated I2t above limit for Phase C 6 14 6 15 7 0 7 1 Active Table 1 Setting Table 1 is the active Table 7 2 Active Table 2 Setting Table 2 is the active Table 7 3 Active Table 3 Setting Table 3 is the active Table 7 4 7 5 7 6 New Events There are new events sto...

Page 15: ...nternal AND gate 10 10 10 AND11 Output of internal AND gate 11 10 11 AND12 Output of internal AND gate 12 10 12 AND13 Output of internal AND gate 13 10 13 AND14 Output of internal AND gate 14 10 14 AND15 Output of internal AND gate 15 10 15 AND16 Output of internal AND gate 16 INTERNAL COMMUNICATION STATUS SIGNALS Group Status Comment 1 0 Remote Local Mode Relay in remote mode 1 1 Rear Connection ...

Page 16: ...t INT TIME Otherwise the unit measures the time between the tripping signal of the main feeder protection and the change of the status contacts of the circuit breaker 52 b The total Breaking Current Limit kI 2 t LIMIT setting fixes the maximum life breaking capability it is recommended to set this to the limit supplied by the manufacturer When this threshold is reached in any phase the system may ...

Page 17: ...RECORDER The DBF system keeps a record of the last 144 events and stores for each one the following information date and time accurate to one millisecond the type of event current RMS values during the event and the state of the unit set of digital signals that describes the status of the relay at any given moment in time This event recorder is stored in a non volatile memory and can be maintained...

Page 18: ...C INIT LO SET A PICKUP LO SET B PICKUP LO SET C PICKUP 3 POLE 50BF INIT NEUTRAL PICKUP ARC A PICKUP ARC B PICKUP ARC C PICKUP The oscillography records are retrieved from the relay to the computer in COMTRADE international standard format using the GE_LOCAL communications program To draw the waveforms digital flags phasors and post fault analysis in general it is suggested to use the GE_OSC oscill...

Page 19: ...he settings table that is active at a given moment The active settings table can be changed by means of up to 2 digital inputs referred to as ACTIVE TABLE SELECT 0 and ACTIVE TABLE SELECT 1 which allow up to 4 combinations from 0 to 3 To do this it is necessary to configure using GE INTRO software two inputs to have these meanings For applications which require less tables up to 2 it is possible t...

Page 20: ...used it has priority over time setting by communications since the time read by IRIG B is much more accurate 2 4 3 CONFIGURABLE INPUTS AND OUTPUTS 2 4 3 1 Digital Inputs The DBF system has 6 digital inputs two groups of 3 inputs with one common in each group The inputs can be configured by the user by means of the GE INTRO configuration program Using the optional expansion board it is possible to ...

Page 21: ...s pick ups trips alarms etc The DBF has 66 different internal states and these can be used to carry out logical operations NOT AND and OR which gives the unit a great flexibility The output configuration is done using different levels At the first level it is possible to use AND gates of up to 16 signals The output is incorporated into the states matrix so that it can then be used in other AND gat...

Page 22: ... characters per line This display has highly reliable LED diode back lighting the screen brightness can be adjusted on the rear of the front board By means of this interface the user can change the settings display measurements carry out operations and access information stored in the unit The functions of this local interface and how to use it are described in the section KEYBOARD AND DISPLAY ...

Page 23: ...K and ModBus RTU The protocol is highly reliable and allows communication with different protection systems It guarantees very efficient data transfer especially for the oscillography and other large files along with error detection and automatic communication recovery The status of the local remote communication is indicated on the front of the unit by LED indicator 16 the last LED in the right h...

Page 24: ...EED On the relay depending on whether communication is through PORT 1 or PORT 2 means LOCAL or PORT 3 means NET STOP BIT Stop bit corresponding to each one of the communication ways LOCAL or NET To modify or view the DBF communication parameters refer to Chapter 8 Section 8 1 Menu Tree IMPORTANT It should be noted that in order to simplify the setting of the unit and for safety reasons all setting...

Page 25: ...e Disable Enable Lo Set C Pickup Enable Disable Enable 3P 50BF Init Enable Disable Enable Neutral Pickup Enable Disable Enable Arc A Pickup Enable Disable Enable Arc B Pickup Enable Disable Enable Arc C Pickup Enable Disable Enable Functions Permitted 50BF 1P function Permitted Non Permitted Non Permitted 50 BF 3P Function Permitted Non Permitted Non Permitted 3P No I Function Permitted Non Permit...

Page 26: ...2t Integration Time In this case the time used will be always the set time should be the rated operating time of the circuit breaker provided by the manufacturer 4 The Pre Fault Cycles to be shown in every oscillography record may be adjusted from two to ten 2 10 In any case the total number of cycles for any oscillography record is 66 regardless of pre fault cycles setting 5 The difference betwee...

Page 27: ...3 SETTINGS 20 DBF Breaker Failure Protection GEK 106168E ...

Page 28: ... Special Models 15 A Revision TABLE 1R RANGES MODELS A B C D E F G DBF PHASE 1 12 A 0 2 2 4 A 1 12A 1 12 A 1 12 A 0 5 6 A 0 5 6 A GROUND 1 12 A 0 2 2 4 A 0 2 2 4 A 0 5 6 A 0 1 1 2 A 0 2 2 4 A 0 1 1 2 A 4 1 1 SPECIAL MODELS The input voltage of the standard model corresponds to the Power Supply voltage The following models have been developed to allow the selection of an input voltage independently...

Page 29: ...0 VDC according to selected model For special models please refer to section 4 1 1 Thermal Capacity Current circuits Permanent 4 x In 3s duration 50 x In 1 s duration 100 x In Temperature ranges Operation 20º C to 55ºC Storage 40ºC to 70ºC Humidity Up to 95 without condensation Trip contacts AC Continuous Capacity 16A Rated Breaking Capacity 4000VA Make 25A for 4 sec Operating Time 8 ms or less DC...

Page 30: ...Community Directive 89 336 for the EC market in line with European standards It also complies with the European directive requirements for low voltage and the environmental and operating requirements established in ANSI standards C37 90 IEC 60255 5 IEC 60255 6 and IEC 68 Test Standard Class Insulation test voltage IEC 60255 5 600V 2kV 50 60 Hz 1 min Impulse voltage IEC 60255 5 5kV 0 5 J 1 MHz inte...

Page 31: ...4 TECHNICAL CHARACTERISTICS 24 DBF Breaker Failure Protection GEK 106168E ...

Page 32: ...DB 9 serial connectors one on the front and two on the rear when using communication option RS 232 One of these connectors is replaced by the corresponding fiber optic connector in models including this option 5 1 3 INTERNAL CONSTRUCTION Internally the DBF unit is divided into 2 trays and a case The case with the blocks of terminals is described above The lower tray carries the magnetic module and...

Page 33: ...168E The communications connectors are situated on left hand side of the front and on the right hand side of the rear of the case The front port is PORT 1 and the rear ports are PORT 2 and PORT3 The IRIG B connection is made using a block of two additional terminals ...

Page 34: ...The analogue digital converter converts the voltage inputs into their digital equivalent with a resolution of 10 bits The unit code is stored in non volatile EPROM memory while the settings and events are stored in EEPROM memory The data related to the oscillography is stored in RAM memory which is maintained using a capacitor thus avoiding the loss of information when the unit is disconnected A h...

Page 35: ...d from the rest of the relay s circuits The power supply provides 12 VDC to the analog circuitry and the output relays and 5 VDC for the digital circuits 5 2 4 KEYBOARD AND DISPLAY The DBF display at the front of the relay is liquid crystal type and consists of two rows of 16 characters each The display has background light with variable lightness adjustable by a potentiometer located on the rear ...

Page 36: ...mage due to transport and handling Check that all the screws are tight and the terminal blocks have not been damaged in any way 6 3 PANEL INSULATION TESTS If any insulation test would be performed on the panel where the relay is installed the ground terminals A9 B9 must remain ungrounded Do the following groups in the terminals of the relay Group 1 A10 B10 Group 2 A1 to A4 B1 to B4 Group 3 C9 C10 ...

Page 37: ...ASE Severe Fault 3P Per Low Load 2P No Per Nº Output Stages 1 2 nd Stage Timer 2s Internal Arc Settings Table 1 Value Int Arc Pickup 1A Int Arc Timer 1s The specific settings required for each test are indicated other settings do not affect the tests 6 5 INDICATORS Check that pressing the TARGET RESET button with relay fed with rated dc power supply all target LEDs light up 6 6 POWER SUPPLY The re...

Page 38: ...to check the communication ports of the relay PORT1 PORT2 and PORT3 To do this it is necessary to use a computer and the communications software GE_LOCAL Figure 7 shows the series cable and connection accessories necessary to establish the connection between the PC and the relay Figure 8 shows the cable and connectors necessary for remote connection by MODEM through PORT3 The PC communication para...

Page 39: ...g status windows turn red while the applied voltage remains present If the relay has the optional expansion board check the same for the following contact converter inputs E7 and E8 CC7 F7 and E8 CC8 E9 and F8 CC9 F9 and F8 CC10 E10 and E11 CC11 F10 and E11 CC12 E12 and F11 CC13 F12 and F11 CC14 6 8 2 IRIG B SYNCHRONIZING INPUT Connect the output of an IRIG B unit with decoded output to the IRIG B...

Page 40: ...ed A12 B12 C4 D4 C5 D5 In case the relay under test includes an expansion board check also the operation of the following contacts E1 F1 E2 F2 E3 F3 9 Check that after 2nd Stage Timer delay 2s the following contacts are closed C1 D1 C6 D6 C7 D7 and if the relay is equipped with an expansion board also the following contacts must be closed E4 F4 E5 F5 E6 F6 10 Repeat steps 7 8 9 and 10 using phase ...

Page 41: ... phase C 8 Energize digital input CC7 3 POLE BF INITIATE if the relay has not an expansion board energize digital inputs CC1 PHASE A BF INITIATE and CC2 PHASE B BF INITIATE simultaneously 9 Check that after T2 time delay 1s the following contacts are closed A12 B12 C4 D4 C5 D5 10 Check that after 2nd Stage Timer delay 2s the following contacts are closed C1 D1 C6 D6 C7 D7 11 Change setpoint TABLE ...

Page 42: ...INGS 3P NO I TIMER T3 to 1s 6 Change setpoint TABLE 1 50BF SETTINGS LOW LOAD 2P to PER 7 Energize digital input CC7 3P BF INITIATE If the relay has not an expansion board energize CC1 PHASE A BF INITIATE and CC2 PHASE B BF INITIATE 8 Check that after 3P NO I TIMER T3 2s the following contacts are closed C4 D4 A12 B12 C5 D5 C1 D1 C6 D6 C7 D7 9 If the relay is provided with an expansion board check ...

Page 43: ...K 106168E 8 Check that after 3P NO I TIMER T3 2s the following contacts are closed A12 B12 C1 D1 C4 D4 C6 D6 C5 D5 C7 D7 9 If the relay is provided with an expansion board check that also the following contacts are closed E1 F1 E2 F2 E3 F3 E4 F4 E5 F5 E6 F6 ...

Page 44: ...ncrease current applied on A1 A2 phase A until contact A12 B12 closes Check that the operating value of the current is within 5 of setpoint 5A for relays with 5A nominal current and 1A for 1A nominal current relays 9 Repeat step 8 applying current on B1 B2 phase B If the relay has not an expansion board energize CC2 PHASE B BF INITIATE 10 Repeat step 8 applying current on A3 A4 phase C If the rela...

Page 45: ...6 ACCEPTANCE TESTS 38 DBF Breaker Failure Protection GEK 106168E ...

Page 46: ...lectronic circuits Then the internal circuitry is perfectly protected In addition this connection also guarantees the physical safety of the personnel when handling the relay since the whole casing is connected to ground 7 3 MAINTENANCE Given the important role that the protection relays play in the operation of any installation a periodic program of tests is highly recommended The unit incorporat...

Page 47: ...7 INSTALLATION AND MAINTENANCE 40 DBF Breaker Failure Protection GEK 106168E ...

Page 48: ...s accessed by keying in the code 7169 In order to access this mode the relay should be on the main screen Single key menu By pressing the ENT key the DBF can be operated in a simplified mode It is not necessary to remove the plastic cover on the front of the relay to access this mode In steady state the DBF shows the following message on the DISPLAY At this point the five groups mentioned above ca...

Page 49: ... In In current in primary Amps I 2 t A COUNTER Accumulated kA 2 sec for phase A Nº OPENINGS Accumulated number opens 3 2 Phase Logic Shows logic for 50BF High Set 50BF Pickup Shows status of 50BF Relay ON OFF Relay ON OF condition 52A Status Breaker Pole A open closed 52B Status Breaker Pole B open closed 52C Status Breaker Pole C open closed LATCHING RELAY 1 Status Latching Relay 1 open closed LA...

Page 50: ... 4000 GENERAL SETTINGS GROUND CT RATIO 1 4000 BREAKER NUMBER 4 digits KI2t OP MODE Fixed Measuring KI2t INT TIME 0 03 0 25 s BREAKER SETTINGS KI2t LIMIT 1 999999 kA2s ACTIVE TABLE SET ACTIVE TABLE 1 3 PREFAULT CYCLES 0 4 PICKUP ENABLE DISABLE 1 st STAGE TRIP ENABLE DISABLE 2 nd STAGE TRIP ENABLE DISABLE INTERNAL ARC ENABLE DISABLE 50BF A TRIP ENABLE DISABLE 50BF B TRIP ENABLE DISABLE 50BF C TRIP E...

Page 51: ...TIMER 0 1 2 0 s INTERNAL ARC SET T2 Same than for TABLE 1 INTERNAL ARC SET T 3 Same than for TABLE 2 To change any setting the procedure is as follows Press the SET key Select the option MODIFY SETTINGS using arrow keys Press ENT key Select the required setting group in the menu tree with arrow keys Press ENT key Select the required specific setting with arrow keys ENTER the value to be modified o...

Page 52: ...ttings do not accepts numeric values instead of that different possibilities will be shown by pressing left right arrow keys To perform MODIFY OF PROTECTION COUNTERS the available menus are Level 1 Level 2 Level 3 Valid Range I2t A COUNTER 0 999999 I2t B COUNTER 0 999999 I2t C COUNTER 0 999999 Nº A OPENINGS 0 9999999 Nº B OPENINGS 0 9999999 MODIFY COUNTERS PROTECTION Nº C OPENINGS 0 9999999 SETTIN...

Page 53: ... of phase A Openings Number of phase B Openings Number of phase C Openings Type of Logic 2P 3P High set Pickup Status A High set Pickup Status B High set Pickup Status C Low set Pickup Status A Low set Pickup Status B Low set Pickup Status C Neutral Pickup Status 50BF Initiation Status A 50BF Initiation Status B 50BF Initiation Status C 50BF 3Pole Initiation Status Arc Pickup A Arc Pickup B Arc Pi...

Page 54: ...lows to set the date and time by entering the year month day hour minutes and seconds in this sequence After each setting the ENT key must be pressed If instead of pressing the ENT key when the SET DATE TIME screen appears the arrow key up or down is pressed the next screen will be shown By pressing ENT key the following sequence will be displayed CONFIRM Yes No OPERATION EXECUTED OPERATION CANCEL...

Page 55: ...le key menu will be accessed Then the information displayed while step by step pressing ENT key is Phase A Current Neutral Current I 2 t Phase A Counter Number of phase A Openings Type of BF Logic 50BF Pickup Status Protection Status Circuit Breaker A Pole Status Circuit Breaker B Pole Status Circuit Breaker C Pole Status Latching Relay 1 Status Latching Relay 2 Status Date and Time ...

Page 56: ...elected by means of the logic key 1 Y for 1 and 3 N for 2 LOC BAUDRATE as above but for local communications LOC STOP BITS As above but for local communications LOCAL SETTINGS Settings changes by local communications allowed not allowed REM SETTINGS Settings changes by remote communications allowed not allowed LOC OPERATIONS Operations being performed by local communications computer directly conn...

Page 57: ...8 KEYBOARD AND DISPLAY 50 DBF Breaker Failure Protection GEK 106168E ...

Page 58: ...FIGURES GEK 106168E DBF Breaker Failure Protection 51 FIGURES FIGURES FIGURES FIGURES ...

Page 59: ...FIGURES 52 DBF Breaker Failure Protection GEK 106168E FIGURE 1 BREAKER FAILURE LOGIC 189C4114 SHEET 2 ...

Page 60: ...FIGURES GEK 106168E DBF Breaker Failure Protection 53 FIGURE 2 EXTERNAL CONNECTIONS 189C4114 SHEET 1 ...

Page 61: ...FIGURES 54 DBF Breaker Failure Protection GEK 106168E FIGURE 3 FRONT VIEW 226B7412 H9 ...

Page 62: ...FIGURES GEK 106168E DBF Breaker Failure Protection 55 FIGURE 4 REAR VIEW 226B7412H10 ...

Page 63: ...FIGURES 56 DBF Breaker Failure Protection GEK 106168E FIGURE 5 DIMENSIONS DIAGRAM 226B6086H10 ...

Page 64: ...FIGURES GEK 106168E DBF Breaker Failure Protection 57 FIGURE 6 PANEL DRILLING 226B6086H10 ...

Page 65: ...2 CONNECTION DBF RELAY TO PC FIGURE 8 RS232 CONNECTION DBF RELAY TO MODEM DB 9 Male Connector Label DB 9 Female Connector DBF NOTE Leave shield unconnected at both ends 1 1 DB 9 Male Connector DB 9 Male Connector NOTE Leave shield unconnected at both ends 1 1 Label DBF ...

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