Troubleshooting; Error Messages; Common Problems And Solutions - Honeywell SC1000 Owner's Manual

10.7 Troubleshooting

10.7.1 Error Messages

10.7.2 Common Problems
and Solutions
Erratic Display
+OVLD or -OVLD on Display
Analog Output Incorrect
" " on Power-up
APPLY 00000
Auxiliary Function Pins Not
Operating
See "Error Messages" on page 151 for information relating to error messages.
Check electrical connections for continuity and the transducer's wiring code from
its Certificate of Calibration.
Make sure that the load on the transducer is constant.
Check millivolt input to the (+)Signal ("+SIG") and (-)Signal ("-SIG") pins with a
voltmeter.
Indicates that the voltage across the (+)Signal ("+SIG") and (-)Signal ("-SIG") pins
is overranging or underranging the amplifier circuit. Make certain all wires are
connected properly.
If you remove all load from the transducer and you still see this message, the
(+)Excitation ("+EXC") or (-)Excitation ("-EXC") pins may be shorted to the (+)Sig-
nal ("+SIG") or (-)Signal ("-SIG") pins.
If you remove all load from the transducer and you get a numeric reading, the
transducer may have a high zero offset. Use the channel's SETUP menu and set
-> to "ON"; in the RUN mode this will allow the [VALUE] but-
DIAGNOSTICS DISPLAY ADC
ton to display raw A/D readings as a percentage of its full-scale. If the raw A/D
readings display more than +/-10% when there is no load on the transducer, the
transducer has a high zero offset.
Make certain of the type of Analog Output (voltage or current) that the channel is
equipped with; see "Identifying the Output Type" on page 76.
Use the ->
DIAGNOSTICS DAC FULL SCALE
force the Analog Output to a known output. Then, adjust your readout device,
panel meter, PLC or data acquisition system to match.
Check the output selection jumpers; see "Output Selection" on page 76.
The channel has detected that the transducer connected to the instrument is dif-
ferent than the one the channel was last calibrated with. Because the
is set to either Shunt Calibration or mV/V Calibration, the instrument is
TYPE
prompting you to apply zero load in order to auto-calibrate to this new transducer.
Do one of the following, depending on the situation:
• Re-connect the original transducer to the channel and re-start the instrument.
• Press [ENTER] to re-calibrate the channel to this new transducer using Shunt
or mV/V Calibration and accept the presently applied load as "0". (In situa-
tions where one can't apply "0" load to an absolute pressure transducer or a
load cell with a pre-load, you can change the
menu item from "0" to a load that can be applied. For example, 14.7
VALUE
PSIA or the known pre-load on the load cell.
• Use the menu item to perform a Known-Load Calibration with this
CALIBRATE
new transducer.
Make sure that the
AUX1 FUNCTION
rectly; if they are set to
DISABLED
The Auxiliary Function ("AUX1" and "AUX2") pins must be connected to pin 10,
and ->
DIAGNOSTICS DAC ZERO SCALE
CALIBRATION DATA
or SETUP menu items are set cor-
AUX2 FUNCTION
then they will not operate.
SC Series Instruction Manual
menu items to
CALIBRATION
->
ZERO-SCALE
page 77