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Install and Wire, Chapter 2

14

        WATLOW Series 942 User's Manual

Output 1 Wiring

Figure 18 -
Process, 0 - 5VDC,
Output 1 Wiring.

Figure 19 -
Solid State Relay
Without Contact
Suppression, Output
1 Wiring.

Process, 0 - 5VDC, Output 1

Model # 942A - _  

H

 

_  _

 -  _ 000

Process Output

Proportional value determined by the control to balance the sensor input and set point.  This
value will fall between 0 - 5VDC depending on the thermal characteristics of the system.

Load impedance is 10K

Ω

 minimum.

18

17

Process, 0-5VDC, Non-Isolated

External 

Load

-

+

+

-

Solid State Relay Without Contact Suppression

Watlow's solid state relay changes state at zero volts, which is "zero-cross switching."  They
are also optically isolated, which means the output circuitry is energized by infrared light
striking a photosensitive device.  This results in a virtual absence of electrically generated
noise, plus output to input electrical isolation.  

Off state impedance is nearly infinite and

should be used to switch high impedance non-inductive loads.

N.O.

COM.

External 

Load

Fuse

L1

L2

18

17

Solid State Relay, Form A, 0.5 Amp

Solid State Relay Without Contact Suppression, Output 1

Model # 942A - 

 

K

  _  _ - _ 000

Summary of Contents for 942 Series

Page 1: ...lo w C o n trols 1241 Bundy Blvd P O Box 5580 Winona MN 55987 5580 Phone 507 454 5300 Fax 507 452 4507 W942 XUMN Rev R00 June 1995 Supersedes W942 MA40 9305 10 00 Made in the U S A Printed on Recycled...

Page 2: ...2 WATLOW Series 985 User s Manual Appendix...

Page 3: ...f the Series 942 4 8 Series 942 Faceplate Dimensions 5 8 Series 942 Panel Cutout Dimensions 6 8 Series 942 Sideview Dimensions 7 9 120 VAC Power Wiring 8 9 240 VAC Power Wiring 9 10 Thermocouple Wirin...

Page 4: ...F control with the switching differen tial selectable under the HYS Setup parameter Two optional auxiliary outputs may be alarms or events An event is an ON OFF mechanical relay output Events are base...

Page 5: ...sure you have the top up to match the plugs with the case The 942 will not fit in the case upside down but check to be sure it is oriented correctly Press the unit in firmly then turn the front panel...

Page 6: ...the case against the front panel The Series 942 behind panel dimensions are 3 6 90 mm high by 3 6 90 mm wide by 6 152 mm deep Figure 5 on the next page shows the dimensions of the front panel bezel Th...

Page 7: ...o 92 79mm 3 622 to 3 653 92 00 to 92 79mm 0 06 to 0 25 1 524 to 6 35mm 3 625 x 3 625 92 08 x 92 08mm Nominal 3 62 to 3 65 92 to 93 mm 3 62 to 3 65 92 to 93 mm 3 63 X 3 63 92 08 X 92 08 mm Your Panel T...

Page 8: ...appear inside the line drawing of the 942 while connections and terminal designations appear outside the line drawing All outputs are referenced to a de energized state The final wiring figure is a t...

Page 9: ...sensor which compensates for lead length resistance When extension wire is used for a three wire RTD all three extension wires must have the same electrical resistance i e same gauge copper stranded R...

Page 10: ...942A 2 _ _ _ _ 000 942A 3 _ _ _ _ 000 A jumper must be installed between Terminals 2 and 3 0 5VDC Process Input Model 942A 2 _ _ _ _ 000 942A 3 _ _ _ _ 000 1 2 3 VDC When using a process input such a...

Page 11: ...device must provide isolation between the SS switch output and load power since the SS switch output is a non isolated output Minimum load resis tance is 500 Available current is 22mA maximum Typical...

Page 12: ...he relay Off state impedance is 20K minimum Mechanical Relay 6 Amp Form C Output 1 Model 942A _ D _ _ _ 000 Mechanical Relay Form C 6 Amp 17 16 18 N O COM External Load Fuse L1 L2 N C Process Output P...

Page 13: ...depending on the thermal characteristics of the system Load impedance is 600 maximum Figure 17 Process 0 20mA Output 1 Wiring Process 0 20mA Output 1 Model 942A _ G _ _ _ 000 Process Output Proportio...

Page 14: ...7 Process 0 5VDC Non Isolated External Load Solid State Relay Without Contact Suppression Watlow s solid state relay changes state at zero volts which is zero cross switching They are also optically i...

Page 15: ...ollector Output 2 Model 942A _ _ C _ _ 000 Figure 20 Solid State Relay With Contact Suppression Output 2 Wiring Switched DC Watlow s solid state switch is a low current DC output open collector used t...

Page 16: ...n electrical and mechanical device with moving parts When power is applied to the relay solenoid contact closure is created through movement of the common contact of the relay Off state impedance is 2...

Page 17: ...ee Chapter 6 Load Fuse L1 L2 Load Fuse L1 L2 24 25 26 27 Mechanical Relay Form A or B 6 Amp Output 4 Output 3 Mechanical Relay 6 Amp Dual Form A or B Auxiliary Output Model 942A _ _ _ 2 _ 000 Mechanic...

Page 18: ...h movement of the common contact of the relay NOTE This output is sup plied with an arc suppression snub ber across the out put terminals High impedance loads may remain ener gized even though the out...

Page 19: ...of the retransmit output An example of this is By setting rL 0 rH 1000 and Ot4 PrOC a process value of 500 will result in a retransmitted signal of 2 5VDC or 12mA 0 5VDC Retransmit Auxiliary Output M...

Page 20: ...ure to observe NEC safety guidelines could result in injury to personnel WARNING Watlow mercury relays are designed to be used only with resistive loads 942A 1DD0 A000 Integral Setpot 140A 16XX 6000 H...

Page 21: ...or 4 Only appears on those units with auxiliary option Lower Display Red 0 56 14 mm high seven segment four digit LED display indicating the set point menu parameters and alarm or error codes L 1 L2...

Page 22: ...pping through the menu it returns to the control set point parameter under the Operation menu Chapter 4 How To Setup The Series 942 Setting up the Series 942 is a simple process First configure the 94...

Page 23: ...d1 rtd 1 0 5 420 Default J or r Decimal Selects the location of the decimal point for all process related data This parameter only appears if the In parameter is 0 5 or 420 Range 0 0 0 0 00 Default 0...

Page 24: ...F 999 F 0 1 F 99 9 F Default 3 F 1 C 540 C 0 1 C 54 0 C 1Unit 999 Units 0 1 Units 99 9 Units Output 3 Selects Output 3 as an alarm or an event This parameter only appears if you have at least one aux...

Page 25: ...JIS 0 003916 C DIN 0 003850 C Range din or JIS Default din Program Type Selects the program type as time based ti or ramp rate rAtE in degrees per minute Changing this parameter erases all profile ste...

Page 26: ...9600 Default 1200 Data Allows the user to select the data bits and parity for communication This parameter appears if your Series 942 has communications Range 7 o 7 data bits and odd parity Default 7...

Page 27: ...999U 3 F 0 1 F 99 9 F 0 1 C 54 0 C 0 1U 99 9U Ot3 AL Ent or no AL AL1 Pr or dE Pr LAt 1 LAt or nLA nLA Dependent on AL 1 Pr or dE HYS3 1 F 999 F 1 C 540 C 1U 999U 3 F 0 1 F 99 9 F 0 1 C 54 0 C 0 1U 9...

Page 28: ...For more information on events see Chapter 6 Range On or OFF Default OFF SP Prog no Ent1 Operation Menu In the Operation menu the 942 operates as a digital set point control Select a set point and the...

Page 29: ...lt 0 00 Reset Integral 2 A reset integral control action for Output 2 that automatically eliminates offset or droop between set point and actual process temperature in a proportional control This para...

Page 30: ...2HI Deviation dE 0 to 999 999 Process Pr A2LO to rH rH Appears if auxiliary output and Ot4 AL CAL 99 F 55 C 99 Units 0 AUt 0 to 3 0 Table 3 Operation Menu Parameters and Descriptions Alarm 1 High This...

Page 31: ...y grasp the necessary terms and concepts by entering and observing your profiles Enter your profile values in the Master Step Chart at the end of the chapter Chapter 5 How to Program Run the Series 94...

Page 32: ...meter only appears if PtYP ti Range 0 to 23 Default 0 Minutes The number of minutes in combination with the HOUr and SEC param eters equaling total step time to achieve the temperature under the StPt...

Page 33: ...rameters are associated with the jumploop step When StEP 1 JL will not appear Jump Step The Series 942 jumps backwards to any step in your file Range 1 to 23 Default 1 Jump Count The number of times t...

Page 34: ...LD RUN key once again your profile begins and the RUN LED is lit If the HOLD RUN key is not pressed twice within 1 minute the RUN function will abort While the profile is RUNning you can only view the...

Page 35: ...On Events OFF StPt SP HOUr Min SEC Ent1 Ent2 rAtE SoAh HOUr Min SEC Ent1 Ent2 JL JS JC End OFF OFFA HOLd Step Step Type Values Time On Events OFF StPt SP HOUr Min SEC Ent1 Ent2 rAtE SoAh HOUr Min SEC...

Page 36: ...the MODE key until you reach the Ot3 parameter The default for Ot3 is AL alarms Change the value to Ent event if it hasn t already been done Press the MODE key to continue on to the Ot4 parameter Do...

Page 37: ...r following the End step is the start of another profile You can continue entering profiles until you run out of steps remember there are a total of 24 steps Jumploop The Series 942 can only jump back...

Page 38: ...for the programmed time Step 4 is an end step signalling the end of the profile 1 When the lower display reads set point press MODE once and you see the Prog parameter Select YES in the upper display...

Page 39: ...ing all outputs Editing Your Profile Now let s try editing the profile by expanding it with another ramp and soak step adding a jumploop and programming the End step to hold We ll jump to Step 1 and r...

Page 40: ...eturns to a standard PID control with the heat PID values automatically set as a result of auto tuning Tuning is complete within 80 minutes Any change of set point while in auto tune re initiates the...

Page 41: ...he best system control However if a mechanical contactor or solenoid is switching power to the load a longer cycle time may be desirable to minimize wear on the mechanical components Experiment until...

Page 42: ...occurs When an event is ON the N O contacts close and the N C contacts open If the L3 or L4 LED on the front panel are lit this indicates an energized event or alarm condition for Output 3 or 4 Changi...

Page 43: ...hing Clear it manually press the HOLD RUN key once as soon as the process temperature is inside the alarm limit according to the HYSX parameter If the alarm is non latching The alarm will clear itself...

Page 44: ...croprocessor is faulty call the factory Er 5 Non volatile checksum error The nonvolatile memory checksum discovered a checksum error Unless a momentary power interruption occurred while the unit was s...

Page 45: ...To clear a corrected error Cycle power to the control or MODE through the SETUP menu until you return to the set point If an error occurs while in the RUN mode the program cannot be resumed Set point...

Page 46: ...3850 0 003850 C Sensor break protection de energizes control outputs to protect system Grounded or ungrounded sensors F C or process variable units are user selectable J t c 32 to 1382 F or 0 to 750...

Page 47: ...ed Retransmit of process or set point User selectable range 0 5VDC into a 10K minimum load non isolated Retransmit of process or set point User selectable range Accuracy Calibration Accuracy and Senso...

Page 48: ...l Relay Form C 6A E Process 0 10VDC non isolated F Process 4 20mA non isolated G Process 0 20mA non isolated H Process 0 5VDC non isolated K Solid State Relay without contact suppression Form A 0 5A 2...

Page 49: ...ce For wiring guidelines refer to the IEEE Standard No 518 1982 available from IEEE Inc 345 East 47th Street New York NY 10017 Noise Sources Switches and relay contacts operating inductive loads such...

Page 50: ...t Using greatly larger wire sizes than required generally will increase the likelihood of electrostatic capacitance coupling of noise Ground loops must be eliminated in the entire control system There...

Page 51: ...doing so repeatedly deteriorates its ability to function MOVs have a limited life Watlow stocks several MOVs See Table 7 Islatrols and other similar power line filters are designed to carry the power...

Page 52: ...d in the system one at a time checking for continuity after each discon nection When continuity reads open you have eliminated the ground loop s Also as you reconnect grounds keep making the continuit...

Page 53: ...This prevents ground loops and maintain filter effectiveness Line Load L2 L1 Ground Co D M Line Filter Shield Figure 42 Differential Mode Filter Wiring NOTE Keep filters 12 305 mm or less from the con...

Page 54: ...walks through the entire calibration param eter list While calibrating a process output the upper display contains a numeric value to be slewed up or down until the output value is correct The control...

Page 55: ...source to 4 00mA Set the current source to 20 00mA Press the UP DOWN keys until Output 1 reads process low Press the UP DOWN keys until Output 1 reads process high Factory select for Output 4 type Pre...

Page 56: ...t is automatically calibrating Your sequence is VERY important Always move to the next parameter before changing the calibration equipment When you have completed all of the thermocouple calibration p...

Page 57: ...in inaccurate calibration values 4 Press the HOLD RUN key twice to enter the RUN mode The unit is calibrating when the RUN LED is ON Make sure the unit is in the RUN mode only when you are in the corr...

Page 58: ...the 0 5 Volt input calibration parameters press the HOLD RUN key twice Failure to do so will result in inaccurate calibration values 4 Press the HOLD RUN key twice to enter the RUN mode The unit is c...

Page 59: ...uipment When you have completed all of the 4 20mA input calibration parameters press the HOLD RUN key twice Failure to do so will result in inaccurate calibration values 4 Press the HOLD RUN key twice...

Page 60: ...Failure to do so will result in inaccurate calibration values 4 Press the HOLD RUN key twice to enter the RUN mode The unit is calibrating when the RUN LED is ON Make sure the unit is in the RUN mode...

Page 61: ...meter before changing the calibra tion equipment When you have completed all of the 4 20mA output calibration parameters press the HOLD RUN key twice Failure to do so will result in inaccurate calibra...

Page 62: ...ameters press the HOLD RUN key twice Failure to do so will result in inaccurate calibration values 4 Press the HOLD RUN key twice to enter the RUN mode The unit is calibrating when the RUN LED is ON M...

Page 63: ...ers press the HOLD RUN key twice Failure to do so will result in inaccurate calibration values 4 Press the HOLD RUN key twice to enter the RUN mode The unit is calibrating when the RUN LED is ON Make...

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