User`s manual

16
WATLOW Series 945 High/Low Limit User's Manual
RTD Field Calibration Procedure
Equipment Required:
•1KΩ precision decade resistance box with 0.01 ohms resolution.
Setup And Calibration
1. Connect the AC line voltage L1, L2, and ground to the proper terminals.
2. Connect the decade resistance box to Terminal #4, 5 and 6 on the ter-minal strip. Use
regular 20 - 24 gauge wire of the same length and type.
3. Apply power to the unit and allow warm up for 15 minutes. After warm-up put the unit
in the CAL menu. See Page 14. Press MODE until rLO s displayed.
4. Press ALARM CLEAR twice to enter the calibration mode. The unit is calibrating when
the ALARM CLEAR LED is ON. Make sure the LED is on only when you are in the
correct parameters. See Figure 16.
5. At rLO set the decade resistance box to the correct low setting below. This can be
calibrated to JIS or DIN. Allow 10 seconds to stabilize. Press MODE.
6. At rHI, set the decade resistance box to the correct high setting. Allow at least 10
seconds to stabilize. The unit leaves the CAL mode if 1 minute passes between key
activations. Press ALARM CLEAR twice to exit the calibration mode. To conclude,
advance the MODE key to the next prompt or exit the CAL menu.
945A-2XX0-0000
945A-3XX0-0000
Calibration Low High
1° 17.31 317.33
0.1° 59.59 177.13
Thermocouple Field Calibration Procedure
Equipment Required:
• Type "J" or "R" Reference Compensator with reference junction at
32°F/0°C, OR Type "J" or "R" Thermocouple Calibrator set at 32°F/0°C.
• Precision millivolt source, 0-50mV min. range, 0.01mV resolution
Setup And Calibration
1. Connect the AC line voltage L1, L2, and ground to the proper terminals.
2. Connect the millivolt source to Terminal #9 Negative and Terminal #7 Positive on the
Series 945 terminal strip. Use regular 20 - 24 gauge wire.
3. Apply power to the unit and allow it to warm up for 15 minutes. After warm-up put the
unit in the CAL menu. See Page 14.
4. Press ALARM CLEAR twice to enter the calibration mode. The unit is calibrating when
the ALARM CLEAR LED is ON. Make sure the LED is on only when you are in the
correct parameters. See Figure 16.
5. At tcL, enter 0.00mV from the millivolt source to the control. Allow 10 seconds to
stabilize. Press MODE.
6. At tcH, enter 50.00mV for type "J" units or 16.035mV for type "R" units from the millivolt
source to the 945. Allow at least 10 seconds to stabilize. Press MODE.
7. At tc, disconnect the millivolt source, and connect the reference compensator or T/C
calibrator to Terminal #9 Negative, and Terminal #7 Positive on the 945 terminal strip.
Allow 10 seconds to stabilize. The unit leaves CAL if 1 minute passes between key
activations. Press ALARM CLEAR twice to exit the calibration mode. To conclude,
advance to the next prompt or exit the CAL menu.
T/C and RTD
NOTE
Before calibration
on an installed
control, make sure
all data and
parameters are
documented. See
Setup, and
Operation Tables,
Pages 12 and 13.
IMPORTANT:
When the ALARM
CLEAR LED is ON
the unit is
automatically
calibrating. Your
sequence is
VERY important.
Always move to the
next parameter
before changing the
calibration
equipment.
Table 4 -
RTD Settings.