Appendix, Specifications, Appendix series 920 specifications – Watlow Series 920 Microprocessor-Based Ramping Control User Manual
Page 59: Mode, Control, Input

Appendix
Series 920 Specifications
Control
Mode
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Microprocessor-based, user selectable modes.
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Single input, dual control outputs, dual auxiliary outputs.
.
99 step programmer with up to 10 profiles.
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Control outputs: User selectable as: Heat, Heat/Cool, Cool, Cool/Heat.
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Outputs independent, or related via dead band.
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ON/OFF: 3°F (1.7°C) switching hysteresis.
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PID parameters.
Proportional band: 0 to 900°F (0 to 500°C), or 0 to 500 units, 0.0 to 90.0°F
(0.0 to 50.0°C) for 0.l° RTD inputs.
Reset: 0.00 to 5.00 repeats per minute.
Rate: 0.00 to 5.00 minutes.
Rate band: 0 to 7 times proportional band.
Cycle time: 1 to 60 seconds.
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Deadband: ±36°F ±20° C), ± 20 units.
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Auxiliary outputs: User selectable as:
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Event per step or alarm.
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Process or deviation value per output.
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Latching or non-latching.
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Separate high and low values per output.
Operator interface
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Membrane front panel.
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Four digit 1/2” (13 mm) LEDs display actual process input value.
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LED indication of °F, °C, or process variable units.
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MODE, ENTER, UP, DOWN, and RUN/HOLD keys.
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Eight character alphanumeric display of operating data.
Input
Thermocouple, RTD and electrical process input.
Lead resistance effect for “J” type thermocouple input: 2OO ohm of lead resis-
tance will cause less than 1°F error. Refer to the lead wire manufacturer’s
specification on ohms per double foot for the type and gauge of wire used.
Automatic cold junction compensation for thermocouple.
RTD input 2 or 3 wire, platinum, 100 ohms @ 0°C, calibrated to JIS curve #3916
(0.003916 ohms/ohms/°C or DIN curve #3850 (0.003850 ohms/ohms/°C
Se lectable in the RTD parameter under the SPCLFUNC menu
Sensor break protection de-energizes control outputs to protect system.
Isolated or grounded sensor. Isolated sensors must be used with process
inputs or outputs.
100K ohms input impedance for 0-5 volt input.
250 ohms input impedance for 4 - 20mA input.
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Operating ranges user selectable.
J t/c:
32 to 1382°F or
0 to 750°C
K t/c:
- 3 2 8 t o 2282°F or -200 to 1250°C
T t/c:
-328 to 662°F or -200 to 350°C
R tic:
32 to 2642°F or
0 to 145O°C
S t/c:
32 to 2642°F or
0 t o 1450°C
B t/c:
3 9 2 t o 3092°F o r 2 0 0 t o 1700°C
1° RTD:
-328 to 1112°F or -200 to 600°C
0.1° RTD: -99.9 to 392.0°F or -99.9 to 200.0°C
0-5VDC:
-99 to 1800 units
4-20mA:
-99 to 1800 units
WATLOW Series 920 User’s Manual
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