7100
Calibration Bath
User's Guide
Rev. 811001
Hart Scientific
Страница 1: ...7100 Calibration Bath User s Guide Rev 811001 Hart Scientific ...
Страница 2: ...ithin the warranty period To obtain warranty service contact your nearest Hart authorized service center or send the product with a description of the difficulty postage and insurance prepaid FOB Destination to the nearest Hart au thorized service center Hart assumes no risk for damage in transit Following warranty repair the prod uct will be returned to Buyer transportation prepaid FOB Destinatio...
Страница 3: ...mental Conditions 9 4 Quick Start 11 4 1 Unpacking 11 4 2 Semi Hermetic Compressor 11 4 3 Set Up 11 4 4 Power 12 4 5 Setting the Temperature 13 5 Installation 15 5 1 Bath Environment 15 5 2 Dry out Period 15 5 3 Bath Preparation and Filling 16 5 4 Probe 16 5 5 Power 16 6 Bath Use 19 6 1 General 19 6 2 Comparison Calibration 19 6 3 Calibration of Multiple Probes 20 7 Parts and Controls 21 7 1 Front...
Страница 4: ...thanol 29 8 1 10 4 Halocarbon 0 8 30 8 1 10 5 Mineral Oil 30 8 1 10 6 Silicone oil 30 8 1 11 Fluid Characteristics Charts 31 8 1 11 1 Limitations and Disclaimer 31 8 1 11 2 About the Graph 31 8 2 Stirring 33 8 3 Power 34 8 4 Heater 34 8 5 Cooling 34 8 6 Temperature Controller 35 9 Controller Operation 37 9 1 Bath Temperature 37 9 2 Reset Cut out 37 9 3 Temperature Set point 39 9 3 1 Programmable S...
Страница 5: ...ommunications 51 10 1 1 Wiring 52 10 1 2 Setup 52 10 1 2 1 Baud Rate 52 10 1 2 2 Sample Period 52 10 1 2 3 Duplex Mode 53 10 1 2 4 Linefeed 53 10 1 3 Serial Operation 53 10 2 IEEE 488 Communication optional 53 10 2 1 Setup 53 10 2 1 1 IEEE 488 Interface Address 54 10 2 2 IEEE 488 Operation 54 10 3 Interface Commands 54 10 4 Power Control Functions 54 10 4 1 Heater Control 57 10 4 2 Cooling Control...
Страница 6: ...ard Lid Top View 25 Figure 6 Fluid Level Adapter 26 Figure 7 Chart of Various Bath Fluids 33 Figure 8 Controller Operation Flowchart 38 Figure 9 Bath temperature fluctuations at various proportional band settings 43 Figure 10 Serial Cable Wiring 52 Figure 11 Sample calibration computations 61 Figure 12 Ice buildup on cooling coils 71 ...
Страница 7: ...d Their Characteristics 32 Table 3 Proportional Band Fluid Table 44 Table 4 Communication Commands 55 Table 5 Communication Commands continued 56 Table 6 Communication Commands continued 57 Table 7 Serial power control functions 58 Table 8 Recommended settings for general operation 58 ...
Страница 8: ...the instrument or in this manual Symbol Description AC Alternating Current AC DC Battery CE Complies with European Union Directives DC Double Insulated Electric Shock Fuse PE Ground Hot Surface Burn Hazard Read the User s Manual Important Information Off On 1 1 Before You Start Symbols Used Table 1 International Electrical Symbols ...
Страница 9: ...eing used 1 2 1 Warnings To avoid personal injury follow these guidelines GENERAL DO NOT use the instrument for any application other than calibration work The instrument was designed for temperature calibration Any other use of the instrument may cause unknown hazards to the user DO NOT use the instrument in environments other than those listed in the user s guide DO NOT overfill the bath Overflo...
Страница 10: ...e burns may result if personnel fail to observe safety precautions ELECTRICAL HAZARD These guidelines must be followed to ensure that the safety mechanisms in this instrument will operate properly This instrument must be plugged into a 230V AC electric outlet of the appropriate frequency The power cord of the instrument is equipped with a three pronged grounding plug for your protection against el...
Страница 11: ...cal system See Section 5 3 Bath Preparation and Filling for specific instruc tions Read Section 6 Bath Use before placing the bath into service DO NOT turn the bath on without fluid in the tank and the heating coils fully immersed DO NOT change the values of the bath calibration constants from the fac tory set values The correct setting of these parameters is important to the safety and proper ope...
Страница 12: ...nds the bath de energizes An amber indicator on the back panel lights when this con dition exists Re energization is automatic upon correction of the fault condition and af ter a delay cycle of about 2 minutes If a fault condition exists upon appli cation of power the bath will not energize Under and Over Voltage Protection at 230 VAC Voltage Cutout 12 5 203 257 VAC Voltage Cut In 7 5 213 247 VAC ...
Страница 13: ...512 3437 E mail xingye han fluke com cn Fluke South East Asia Pte Ltd Fluke ASEAN Regional Office Service Center 60 Alexandra Terrace 03 16 The Comtech Lobby D 118502 SINGAPORE Phone 65 6799 5588 Telefax 65 6799 5588 E mail antng singa fluke com When contacting these Service Centers for support please have the following information available Model Number Serial Number Voltage Complete description ...
Страница 14: ...t LED display and four key switches Digital remote communications is optionally available with a RS 232 or IEEE 488 interface The tank for the 7100 is stainless steel and holds 18 liters The refrigeration system is a unique two stage cascade design featuring CFC Free refrigerants 7 2 Introduction COOLING TEMPERATURE EVAPORATING TEMPERATURE COOLING POWER HIGH HIGH STAGE LOW STAGE LOW SET COOLING TE...
Страница 15: ...3 x 48 3 cm Shipping Weight 400 lbs 182 kg Temperature Drift per C Ambient or 10 volts AC line 0 5m C Safety OVERVOLTAGE Installation CATEGORY II Pollution Degree 2 per IEC1010 1 3 2 Environmental Conditions Although the instrument has been designed for optimum durability and trou ble free operation it must be handled with care The instrument should not be operated in an excessively dusty or dirty...
Страница 16: ... 75kPa 106kPa mains voltage within 10 of nominal vibrations in the calibration environment should be minimized altitude does not effect the performance or safety of the unit 7100 Calibration Bath User s Guide 10 ...
Страница 17: ...s Hole Cover Controller Probe Users Guide Drain Elbow Report of Test Fill Hole Cover 9930 Interface it Software and Users Guide optional If you are missing any item please call an Authorized Service Center see Sec tion 1 3 4 2 Semi Hermetic Compressor The semi hermetic compressor s located below the bath have had their mounting hardware tightened down to avoid damage during shipment In addi tion s...
Страница 18: ...nd plugged into the socket at the back of the bath The bath stirrer and haeater must be plugged in Connectors are different to prevent improper connections 4 4 Power Plug the bath power cord into a mains outlet of the proper voltage frequency and current capability 230 VAC 10 60 Hz 15 amp 50 Hz optional Set the HEATER switch on the front panel to position LOW and turn the bath on using the front p...
Страница 19: ... is cur rently being used and its value Eight set point memories are available S Access set point selection 1 25 0 Set point 1 25 0 C currently used Press SET to select this memory and access the set point value S Access set point value C 25 00 Current value of set point 1 25 00 C Press UP or DOWN to change the set point value U Increment display C 30 00 New set point value Press SET to accept the...
Страница 20: ...perature be careful not to exceed the temperature limit of the bath fluid The over temperature cut out should be correctly set for added safety See Section 9 8 If operating the bath below 45 C set the COOLING power switch to ON The cooling temperature or cooling power may require adjustment to provide the proper amount of cooling See Section 8 5 To obtain optimum control stability adjust the propo...
Страница 21: ...he crate The area containing the compressors will be heavier than the rest of the bath If it is required to move the bath after installation empty the bath of fluid DONOT move a bath filled with fluid The back of the bath which is where the compressors are located is heavier than the front To safely move the bath two people are required Do not attempt to carry the bath it is tall and ex tremely he...
Страница 22: ...spilling on the stirring motor while filling Note Underfilling may reduce bath performance and may possibly damage the bath heater 5 4 Probe Inspect the bath controller probe This probe should not be bent or damaged in any way Reasonable caution should be used in handling this probe as it con tains a precision platinum sensor and is mechanically shock sensitive Drop ping striking or other physical...
Страница 23: ...s the voltage to the compressors to a nomi nal operating 200 volts 50 Hz units made to operate on 200 230 volts are not supplied with a transformer Use only wires and a circuit which are capable of supplying the maximum 20 amperes of current The wires must be fastened securely and insulated well Plug the stirring motor power cord into the STIRRER socket at the back of the bath Plug the heater powe...
Страница 24: ...heat cold resistant surface or rack until they are at room temperature It is advisable to wipe the probe with a clean soft cloth or paper towel before inserting it into another bath This prevents the mixing of fluids from one bath to another If the probe has been calibrated in liquid salt carefully wash the probe in warm water and dry completely before transferring it to another fluid Always be su...
Страница 25: ...hen calibrating over a wide temperature range better results can generally be achieved by starting at the highest temperature and progressing down to the lowest temperature Probes can be held in place in the bath by using probe clamps or drilling holes in the access cover Other fixtures to hold the probes can be designed The ob ject is to keep the reference probe and the probe s to be calibrated a...
Страница 26: ...arious other bath functions settings and constants The display shows temperatures in values according to the selected scale units C or F 2 The control buttons SET DOWN UP and EXIT are used to set the bath temperature set point access and set other operating parameters and access and set bath calibration parameters A brief description of the functions of the buttons follows 21 7 Parts and Controls ...
Страница 27: ...ling switch controls power to the cooling compressors and cool ing fan 7 2 Refrigeration Controls The front panel refrigeration control area has four features see Figure 3 bot tom 7 the cooling power switch 8 the cooling temperature regulating valve 9 the cooling temperature pressure gauge and 10 cascade refrigeration indi cator lights 7 The cooling power switch is used to control the cooling capa...
Страница 28: ...h stage compressor for the second or low stage compressor to be automatically engaged 7 3 Back Panel The back panel has the following features see Figure 4 1 the probe connec tor 2 the stirrer power outlet 3 the system fuses 4 the heater power outlet 5 6 optional serial and IEEE interface connectors 7 the terminal box for power connection and 8 the bath drain 1 The probe connector on the back pane...
Страница 29: ...es for connecting the bath to AC power The bath requires 230 VAC 10 60 Hz 20 A 8 A drain valve is provided for ease of removing the fluid media from the bath Always use a container of adequate size to hold the full load of fluid Some oils are more easily drained at higher temperatures See caution note below 7100 Calibration Bath User s Guide 24 1 3 4 5 6 7 8 2 Figure 4 Back Panel ...
Страница 30: ...the floor or other objects that may be damaged by high temperatures as required 7 4 Lid There are two different types of lids see Figure 5 on page 25 The standard lid has a stirring motor with an access hole and the optional fluid level adapter has a cover and sight glass see Figure 6 on page 26 Their features are described with reference to figure numbers as follows 25 7 Parts and Controls Lid 2 ...
Страница 31: ... the optional pump lid 3 The probe hole is for inserting the control probe into the bath 7 5 Fluid Level Adapter The fluid level attachment connects to the fluid well by means of a bayonet type mount see Figure 6 It s cover is attached by four screws and the sight glass sits on the cover It is designed to bring the fluid level to the top of the lid for convenience in observing the meniscus of liqu...
Страница 32: ...of the fluid 8 1 2 Viscosity Viscosity is a measure of the thickness of a fluid how easily it can be poured and mixed Viscosity affects the temperature uniformity and stability of the bath With lower viscosity fluid mixing is better therefore creating a more uni form temperature throughout the bath This improves the bath response time which allows it to maintain a more constant temperature For goo...
Страница 33: ...ds degrade over time because of vaporization water absorption gel ling or chemical breakdown Often the degradation becomes significant near the upper temperature limit of the fluid 8 1 8 Safety When choosing a fluid always consider the safety issues associated Obviously where there are conditions of extreme hot or cold there can be danger to people and equipment Fluids may also be hazardous for ot...
Страница 34: ...mited temperature range from a few degrees above 0 C to a few degrees below 100 C At higher temperatures evaporation becomes significant Water used in the bath should be distilled or deionized to prevent mineral deposits Consider using an algicide chemical in the water to prevent contamination 8 1 10 2 Ethylene Glycol The temperature range of water may be extended by using a solution of 50 water a...
Страница 35: ...y by heating the fluid up to 100 C for brief periods of time Use halocarbon 0 8 under a fume hood at higher temperatures to remove vapors Toxicity is low but caution is always recommended Halocarbon 0 8 has excel lent electrical resistivity This fluid is fairly expensive 8 1 10 5 Mineral Oil Mineral oil or paraffin oil is often used at moderate temperatures above the range of water Mineral oil is ...
Страница 36: ...n used as heat transfer fluid in baths Because of the temperature range some fluids may not apply to your bath 8 1 11 2 About the Graph The fluid graph visually illustrates some of the important qualities of the fluids shown Temperature Range The temperature scale is shown in degrees Celsius A sense of the fluid s general range of application is indicated Qualities including pour point freeze poin...
Страница 37: ...6 C fl 168 C 15 75 C 5 125 C 0 87 25 C 0 84 75 C 0 81 125 C 0 48 25 C 0 53 75 C 0 57 125 C 0 00025 25 C 0 0007 50 C 5 25 C Silicone Oil Type 200 05 5010 40 C v 130 C fl cc 133 C 5 25 C 0 92 25 C 0 4 0 00028 25 C 0 00105 1000 25 C 10 150 C Silicone Oil Type 200 10 5012 30 C v 209 C fl cc 211 C 10 25 C 3 135 C 0 934 25 C 0 43 40 C 0 45 100 C 0 482 200 C 0 00032 25 C 0 00108 1000 25 C 50 150 C Silico...
Страница 38: ...centistokes Lighter shading represents decreasing viscosity while vaporization and decomposition increase Black area represents liquid range with excessive viscosity Range over which a fume hood is recommended 10 CS FL 302 C PP Silicone Oil 5017 Silicone Oil 5014 10 CS FL 280 C PP Silicone Oil 5013 10 CS FL 232 C PP Silicone Oil 5012 10 CS FL 211 C PP Silicone Oil 5010 10 CS FL 133 C PP EP 100 C H...
Страница 39: ...when the heater is off The indicator pulses constantly when the bath is maintaining a sta ble temperature The heater has two power level settings The HIGH heater power setting is used to quickly heat the bath fluid up to the desired operating temperature The HIGH heater power setting may also be required for control at high tempera tures The LOW setting is used for control at lower temperatures an...
Страница 40: ...est bath stability the cooling should be adjusted to allow the heater power to operate between 10 and 50 For temperatures above 60 C set to approximately 90 psig and regulate the cooling power with the cooling power switch For maximum cooling for ramping down and controlling at lower temperatures the cooling power should be switched to HIGH and the cooling pressure should be set to 2 Hg Readjust h...
Страница 41: ... and programmed from the front control panel using the four key switches and digital LED display The controller may also be optionally equipped with a serial RS 232 or IEEE 488 GPIB digital interface for remote operation Operation of the controller using the front control panel is discussed following in Section9 Operation using the digital interfaces is dis cussed in Section10 When the controller ...
Страница 42: ...e in degrees Celsius The temperature display function may be accessed from any other function by pressing the EXIT button 9 2 Reset Cut out If the over temperature cut out has been triggered the temperature display will alternately flash cut out Indicates cut out condition The message continues to flash until the temperature is reduced and the cut out is reset The cut out has two modes automatic r...
Страница 43: ...XIT Probe Menu R0 ALPHA Adj R0 Adj ALPHA SET EXIT Serial Interface Menu BAUD Rate Adjust BAUD Rate Sample Period Adj Sample Period Duplex Mode Adj Duplex Mode Linefeed Adjust Linefeed EXIT EXIT EXIT EXIT EXIT EXIT EXIT EXIT EXIT EXIT SET Display Power Set Proportional Band Set Cutout Temp EXIT EXIT EXIT SET SET SET SET SET SET SET SET SET SET Reset Cutout Select Setpoint Adjust Setpoint EXIT EXIT ...
Страница 44: ...temperature should also be set below the upper limit of the fluid Setting the bath temperature involves three steps 1 select the set point mem ory 2 adjust the set point value and 3 adjust the vernier if desired 9 3 1 Programmable Set points The controller stores 8 set point temperatures in memory The set points can be quickly recalled to conveniently set the bath to a previously programmed tem pe...
Страница 45: ... 3 Set point Vernier The set point value can be set with a resolution of 0 01 C The user may want to adjust the set point slightly to achieve a more precise bath temperature The set point vernier allows one to adjust the temperature below or above the set point by a small amount with very high resolution Each of the 8 stored set points has an associated vernier setting The vernier is accessed from...
Страница 46: ...proportional band and cut out set point The temperature scale units selection is accessed after the vernier adjustment function by pressing SET From the temperature display function access the units selection by pressing SET 4 times 25 00 C Bath temperature S Access set point memory 1 25 0 Set point memory S Access set point value C 25 00 Set point value S Access vernier 0 00000 Vernier setting S ...
Страница 47: ...f heating the user can tell if the bath is heating up to the set point cooling down or controlling at a constant temperature Monitoring the percent heater power lets the user know how stable the bath temperature is With good control stability the percent heat ing power should not fluctuate more than 1 within one minute The heater power display is accessed in the secondary menu Press SET and EXIT s...
Страница 48: ...eat thermal conduc tivity heater power setting operating temperature and stirring Thus the pro portional band width may require adjustment for best bath stability when any of these conditions change Of these the most significant factors affecting the op timum proportional band width are heater power setting and fluid viscosity The proportional band should be wider when the higher power setting is ...
Страница 49: ... band setting To change the proportional band press UP or DOWN D Decrement display Pb 0 060C New proportional band setting 7100 Calibration Bath User s Guide 44 Fluid Temperature Heater Setting Proportional Band Stability Methanol 100 C Low 0 04 C 0 005 C Methanol 80 C Low 0 04 C 0 005 C Methanol 40 C Low 0 04 C 0 003 C Water 0 0 C Low 0 04 C 0 003 C Water 30 0 C Low 0 04 C 0 003 C Water 60 0 C Lo...
Страница 50: ...upper temperature limit of the bath If the cut out is activated because of excessive bath temperature then power to the heater is shut off and the bath cools The bath cools until it reaches a few degrees below the cut out set point temperature At this point the action of the cut out is determined by the setting of the cut out mode parameter The cut out has two selectable modes automatic reset or m...
Страница 51: ...he UP and DOWN keys and then pressing SET 9 10 Probe Parameters The probe parameter menu is indicated by PrObE Probe parameters menu Press SET to enter the menu The probe parameters menu contains the pa rameters R0 and ALPHA which characterize the resistance temperature rela tionship of the platinum control probe These parameters may be adjusted to improve the accuracy of the bath This procedure i...
Страница 52: ...er Press SET to access the parameter setting Normally the cut out is set for manual mode Cut out set for manual reset To change to automatic reset mode press UP and then SET Cut out set for automatic reset 9 12 Serial Interface Parameters The serial RS 232 interface parameters menu is indicated by SErIAL Serial RS 232 interface parameters menu The Serial interface parameters menu contains paramete...
Страница 53: ...mple rate is set to 5 the bath transmits the current measurement over the serial interface approximately every five seconds The automatic sampling is disabled with a sample period of 0 The sample period is indicated by SAmPLE Serial sample period parameter Press SET to choose to set the sample period The current sample period value will be displayed SA 1 Current sample period seconds Adjust the va...
Страница 54: ...rameter LF On Current linefeed setting The mode may be changed using UP or DOWN and pressing SET LF OFF New linefeed setting 9 13 IEEE 488 Parameters Baths may optionally be fitted with an IEEE 488 GPIB interface In this case the user may set the interface address within the IEEE 488 parameter menu This menu does not appear on baths not fitted with the interface The menu is indicated by IEEE IEEE ...
Страница 55: ...f these parameters is im portant to the safety and proper operation of the bath The calibration parameters menu is indicated by CAL Calibration parameters menu Press SET five times to enter the menu 9 14 1 CTO Parameter CTO sets the calibration of the over temperature cut out This is not adjustable by software but is adjusted with an internal potentiometer For the 7100 baths this parameter should ...
Страница 56: ... controlled using the interface To enable the heater to be switched to high using the interface the HEATER switch must be set to the LOW position The COOLING switch must be set to OFF and the COOL ING POWER switch set to HIGH to enable remote control Adjust the cool ing temperature to the minimum desired Digital Interface Setup HEATER switch LOW COOLING switch OFF COOLING POWER switch HIGH COOLING...
Страница 57: ...face menu is indicated with SErIAL Finally press SET to enter the serial parameter menu In the serial interface parameters menu are the BAUD rate the sample rate the duplex mode and the linefeed parameter 10 1 2 1 Baud Rate The baud rate is the first parameter in the menu The display will prompt with the baud rate parameter by showing BAUd Press SET to choose to set the baud rate The current baud ...
Страница 58: ...n The mode may be changed using UP or DOWN and pressing SET 10 1 3 Serial Operation Once the cable has been attached and the interface set up properly the control ler immediately begins transmitting temperature readings at the programmed rate The set point and other commands may be sent to the bath via the serial interface to set the bath and view or program the various parameters The inter face c...
Страница 59: ... be used to either set a parameter or display a parameter depending on whether or not a value is sent with the command following a character For example s CR will return the current set point and s 50 00 CR will set the set point to 50 00 degrees In the following list of commands characters or data within brackets and are optional for the command A slash denotes alternate characters or data Numeri...
Страница 60: ...ad proportional band setting pr op band pr pr 999 9 pr 15 9 Set proportional band to n pr op band n pr 8 83 Depends on Configuration Read cutout setting c utout c c 9999 x xxx c 620 C in Set cutout setting c utout n r eset Set cutout to n degrees c utout n c 500 Temperature Range Reset cutout now c utout r eset c r Read heater power duty cycle po wer po po 9999 po 1 Configuration Menu Probe Menu R...
Страница 61: ...b0 n b0 0 999 9 to 999 9 Read BG calibration parameter bg bg bg 999 99 bg 156 25 Set BG calibration parameter to n bg n bg 156 25 999 9 to 999 9 Read low set point limit value tl ow tl tl 999 tl 80 Set low set point limit to n tl ow n tl 80 999 9 to 999 9 Read high set point limit value th igh th th 999 th 205 Set high set point limit to n th igh n th 205 999 9 to 999 9 Miscellaneous not on menus ...
Страница 62: ...and Setting the F2 value to 0 turns the refrigeration off and setting it to 1 turns it on F2 alone returns 0 or 1 showing the state of the re frigeration power control 57 10 Digital Communication Interface Power Control Functions Command Description Command Format Command Example Returned Returned Example Acceptable Values Set Expansion Valve 1 to off f3 n f3 0 Read Cooling Power f4 f4 f4 9 f4 1 S...
Страница 63: ...perature ranges Actual pressures may ve varied for specific applications Table 7 summarizes the serial control functions for heating and cooling Table 8 shows the recommended control settings for each operating temperature range The ranges may need to be adjusted depending on the bath and its particular use 7100 Calibration Bath User s Guide 58 Function Command 0 1 Heater F1 low high Refrigeration...
Страница 64: ...ath may achieve an accuracy of maybe 0 03 C over the range 10 to 110 C Choosing 30 C and 70 C may allow the bath to have a better accuracy of maybe 0 01 C over the range 25 to 75 C but outside that range the accuracy may be only 0 05 C 11 2 Measuring the Set point Error The first step in the calibration procedure is to measure the temperature errors including sign at the two calibration temperatur...
Страница 65: ...the new values R0 and ALPHA would be computed as 99 885 and 0 0038302 re spectively Program the new values R0 and ALPHA into the controller Check the calibration by setting the temperature to tL and tH and measuring the errors again If desired the calibration procedure may be repeated again to further im prove the accuracy 11 4 Calibration Example The bath is to be used between 25 and 75 C and it ...
Страница 66: ... tH 80 00 C measured t 79 914 C Compute errors errL 29 843 30 00 C 0 157 C errH 79 914 80 00 C 0 086 C Compute R0 R0 0 086 30 0 0157 80 0 80 0 30 0 0 00385 1 100 000 100 077 Compute ALPHA ALPHA 1 0 00385 80 0 0157 1 0 00385 30 0 0 086 80 0 30 0 1 0 00385 0 0038416 Figure 11 Sample calibration computations ...
Страница 67: ...lication Heat transfer medium lifetime is dependent upon the type of medium and the environment The fluid should be checked at least every month for the first year and regularly thereafter This fluid check provides a baseline for knowledge of bath operation with clean usable fluid Once some fluids have become compromised the break down can occur rapidly Particular attention should be paid to the v...
Страница 68: ...the equip ment design the operation of the bath may be impaired or safety hazards may arise The over temperature cut out should be checked every 6 months to see that it is working properly In order to check the user selected cut out fol low the controller directions Section9 2 for setting the cut out Both the manual and the auto reset option of the cut out should be checked Set the bath temperatur...
Страница 69: ...to find and solve the problem Several possible problem conditions are described along with likely causes and solutions If a problem arises please read this section carefully and attempt to understand and solve the problem If the probe seems faulty or the problem cannot otherwise be solved contact an Authorized Service Center see Section 1 3 on page 5 for assistance Be sure to have the instrument m...
Страница 70: ...ng power at all first check the heater fuses If a fuse is burned out try re placing the fuse with a new one of the type and rating and then check to see if the bath resumes normal opera tion If the fuse blows again there may be a shorted heater As a last resort a Factory Reset Sequence may need to be performed See Troubleshooting Section The display flashes Cut out and an incorrect process tempera...
Страница 71: ...an Au thorized Service Center see Section 1 3 on page 5 for assistance The display flashes cutout and an incorrect process temperature The problem may be that the controller s voltmeter circuit is not func tioning properly A problem could exist with the memory back up battery If the battery voltage is insufficient to maintain the mem ory data may become scrambled causing problems A nearby large st...
Страница 72: ...er controls or at tempts to control at an inaccurate temperature The controller operates normally except when controlling at a speci fied set point At this set point the temperature displayed does not agree with the temperature measured by the user s reference ther mometer to within the specified accuracy This problem may be caused by an actual difference in temperature between the points where th...
Страница 73: ...the proportional band until the temperature stabilizes as discussed in Section 9 7 Proportional Band The controller erratically heats then cools control is unstable If both the bath temperature and output power do not vary periodically but in a very erratic manner the problem may be excess noise in the system Noise due to the control sensor should be less than 0 001 C However if the probe has been...
Страница 74: ...be used to 100 C should be approximately 95 methanol and 5 water by volume or approximately 93 methanol and 7 wa ter by weight Methanol if incorrectly mixed or not mixed at all with water will cause the following prob lems If no water is mixed with methanol the methanol will freeze on the cooling coil as seen in Figure 12 and the bath usually will not cool much below 97 C If too much water is mixe...
Страница 75: ...ing a memory check is the easiest way to verify the ability of the battery to maintain controller parameters 1 Power off the instrument 2 Disconnect the instrument from AC power for 10 seconds 3 Reconnect the AC power and power on the instrument 4 If the display shows InIT and or the cycle count shows a low num ber such as 0002 the battery is spent and should be replaced Con tact an Authorized Ser...
