Red Lion PCU - Manual (Page 86)

APPENDIX “E” - CALIBRATION
CALIBRATION CHECK
The instrument has been fully calibrated at the factory for the voltage and
current inputs. If the unit appears to be indicating or controlling incorrectly,
see
Troubleshooting, page 73, before attempting this procedure.
If the controller is suspected of reading incorrectly, the instrument may be
checked for indication accuracy without disturbing the factory calibration.
The parameters to be checked are: voltage reading, mA reading, linear DC
output, Second Input, and Valve Position Feedback. The following
procedures may be used for this purpose.
Note: Allow 1/2 hour warm-up with the controller in an upright position to allow
adequate ventilation to the case before checking these parameters.
VOLTAGE READING CHECK
1. Connect a DC volt source with an accuracy of 0.01% or better to terminal #8
(+) and terminal #10 (-).
2. Advance to the configuration parameter modules from the normal display
mode.
3. Set the controller to indicate voltage (VOLt), in the input parameter module.
4. Press the “PAR” key until “INP 1” appears in the main display.
5. Press the “DSP” key, once, the “%PW” & “DEV” annunciators will flash.
6. The secondary display will indicate voltage applied at Terminals 8 & 10.
7. Compare the controller read-out to the standard at various points over the
range (0-10 V). The tolerance is 0.15% of reading ± 1 LSD.
8. Calibrate the controller if the readings are out of tolerance.
CURRENT READING CHECK
1. Connect a current source with an accuracy of 0.01% or better to terminal #9
(+) and terminal #10 (-).
2. Advance to the configuration parameter modules from the normal display
mode.
3. Set the controller to indicate current (Curr), in the input parameter module.
4. Press the “PAR” key until “INP 1” appears in the main display.
5. Press the “DSP” key, once, the “%PW” & “DEV” annunciators will flash.
6. The secondary display will indicate the current applied at Terminals 9 & 10.
7. Compare the controller read-out to the standard at various points over the
range (4 to 20 mA). The tolerance is 0.15% of reading ± 1 LSD.
8. Calibrate the controller if the readings are out of tolerance.
LINEAR DC OUTPUT CHECK
4 to 20 mA
1. Connect an ammeter to the linear output (#11 & #12) with an accuracy of
0.1% or better.
2. Set “ANAS” (Analog Assignment) to “INP”, in Configure Input
Parameters.
3. Drive the input signal level below the programmed “ANLO” value. Check
for 4 mA (±0.02 mA).
4. Drive the input signal level above the programmed “ANHI” value. Check
for 20 mA (±0.03 mA).
5. Calibrate the controller linear DC output if out of tolerance.
0 to 10 VDC
1. Connect a voltmeter to the linear output (#11 & #12).
2. Set “ANAS” (Analog Assignment) to “INP”, in Configure Input
Parameters.
3. Drive the input signal level below the programmed “ANLO” value. Check
for 0 VDC (±20 mV).
4. Drive the input signal level above the programmed “ANHI” value. Check
for 10 VDC (±30 mV).
5. Calibrate the controller linear DC output if out of tolerance.
SECOND INPUT CHECK
The Second Input Check applies to those models that have the Second
Analog Input (Remote Setpoint) and Valve Positioner options. Different
signals are required for each option.
Second Analog Input Check
1. Apply signals over the range of 0 to 20 mA DC to the terminals labeled
Second Input, 4-20 mA+ and 4-20 mA-. The tolerance is 0.2% of full scale
± 1 LSD.
2. Calibrate the Second Analog Input if out of tolerance.
Valve Positioner Check
1. Apply signals derived from the resistor string as described in Valve
Positioner Calibration. The tolerance is 0.2% of full scale ± 1 LSD.
2. Calibrate the Second Analog Input if out of tolerance.
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