0-5/0-10 Volt Output Field Calibration Procedure
Equipment Required
l
20K ohm, 1/4 watt, 10% resistor
l
4
-
1/2 digit Digital Multimeter.
Setup And Calibration
NOTE
NOTE:
Not all parameters
will
appear. They
are dependent on
your
unit type. Use
only the steps that
apply to your unit.
1.
2.
3.
Before calibration on an installed control, make sure all data and
parameters are documented. See Setup and Operation Charts,
Pages 26 and 26.
Connect the AC line voltage
Ll
,
L2,
and ground to the proper terminals of
the 980/985. See Chapter 2.
Connect the multimeter across the 20K ohm resistor to Terminai #1 (+) and
#3 (-) for 0-5VDC or 0-10VDC units, on the Series 980/985 terminal strip.
Use regular 20
-
24 gauge wire.
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 Figure 33 on Page 37.
Press the MODE key until the 4A0 prompt is displayed.
IMPORTANT:
When the MANUAL LED is ON the unit is automatically calibrating. Your
sequence is VERY important. Always move to the next prompt before
changing the calibration equipment.
4.
5.
6.
7.
8.
9.
Press the AUTO/MAN key twice to enter the MANUAL mode. The unit is
calibrating when the MANUAL LED is ON.
At the 4A0 prompt, the multimeter should read approximately 0.000V.
Allow at least 10 seconds to stabilize.
Use the UP/DOWN keys (reverse acting) to adjust the reading on the
multimeter for 0.0V±0.10V
.
Press the MODE key.
At the 2AO prompt, the multimeter should read approximately 5.000V for
0-5 volt units, or 1 0.000V for 0-10 volt units. Allow at least 10 seconds to
stabilize.
Use the UP/DOWN keys (reverse acting) to adjust the reading on the
multimeter for 5.0V ±0.10V on 0-5V units and 10.0V+/-0.1 OV on 0-1 OV
units.
Press the AUTO/MAN key twice to exit the MANUAL mode. This pauses
calibration to exit the CAL mode.
Appendix
WATLOW Series 980/985 User’s Manual
43
