Manual

Field Calibration
Technical Reference
76 WATLOW Series 1500 User's Manual
Field Calibration, Appendix
Calibrate Channel 1 °F Output
7. Remove (+) plus lead from E-120 and connect to Term. 4. Set Ch-1 input to
(92.93) [93.03] ohms. Adjust Ch-1 SC-Lo pot for 0.000V on DVM. Ch-1
Actual should be 000.0 ± 0.5°F (-18°C).
8. Set Ch-1 input to (294.91) [291.56] ohms and adjust Ch-1 SC-Hi pot for
4.950VDC. Actual should read 990.0° ± 0.5°F (532°C).
9. Repeat Steps 7 and 8 until all the readings are correct with no further
adjustment necessary.
10. Set Ch-1 input to (199.37) [197.69] ohms. DVM should read 2.50VDC. Actual
should read 500° ± 1.0°F (260°C).
Calibrate Channel 2 °F Output
11. Remove DVM (+) plus lead from Term. 4 and connect to Term. 3. Set Ch-2
input to (92.93) [93.03] ohms. Adjust Ch-2 SC-Lo pot for 0.000V on DVM.
12. Set Ch-2 input to (294.91) [291.56] ohms and adjust Ch-2 SC-Hi pot for
4.950VDC on DVM.
13. Repeat Steps 11 and 12 until all the readings are correct with no further
adjustment necessary.
Calibrate %RH Output
14. Remove DVM (+) plus lead from Term. 3 and connect to Term. 2. Set Ch-1 and
Ch-2 inputs to (136.59) [135.97] ohms. Adjust F.S. pot for 0.500VDC on
DVM. Ch-2 Actual should read 100.0 ± 1.0.
15. Set Ch-2 input to (112.75) [112.53] ohms. Adjust zero pot for 0.000VDC on
DVM. Ch-2 should read 00.0 ± 1.0.
16. Repeat Steps 14 and 15 until readings are correct.
17. Set Ch-2 input to (132.28) [131.74]. DVM should read 0.325± 0.005VDC and
Ch-2 Actual should read 64.4 ±1.0.
Calibrate Channel 1 °C Output
18. Power down control. Set DIP Switch #7 ON.
19. Disconnect DVM (+) plus from Term. 2 and connect to Term. 11. Power up
control. Set Ch-1 input to (100.00) [100.00] ohms. Ch-1 Actual should read
000.0°C. Adjust °C Lo pot for 0.00V on DVM.
20. Set Ch-1 input to (284.04) [280.90] ohms. Ch-1 Actual should read 500.0°C.
Adjust °C Hi pot for 2.500VDC on DVM.
21. Repeat Steps 19 and 20 until readings are correct.
22. Set Ch-1 input for (195.70) [194.07] ohms. Actual should read 250.0°C. DVM
should read 1.25VDC.
NOTE:
#13 thru #16
required only if
%RH analog
output is used.
NOTE:
#17 thru #21
required only if °C
analog output is
used.
%RH analog
output does not
work with a
voltage input on
Channel 2