Omicron CMC 430, Руководство пользователя

Страница: 49 / 53

5.2 Potential errors, possible causes, remedies
Some potential disruptions that may occur while operating the CMC 430 are listed below. Try to
eliminate them by applying the remedies proposed here.
Error Possible causes Remedies
Power switch does not light up
after turning on the
CMC 430
test set.
There is no power to the test set. Check the power supply and
assure that it supplies power to
the test set.
Malfunction of internal test set
components. Contact OMICRON
(→
Support on page 52).
The following message appears
in the status line of the
controlling software or device:
"WARNING: Broken ground
connection! Immediately turn off
the test set! Resuming the
operation can result in hazard to
life and is done at your own risk." Ground-wire connection to the
CMC 430 is broken or the test
set is powered by an earth-free
power supply.
Note: Never connect the
CMC 430 to an isolating
transformer.
Check the ground connection.
Ground the housing of the test
set separately using the
grounding terminal on the front
plate.
5.3 Overheating
Depending on the output current, the compliance voltage setting and the ambient temperature, a duty
cycle smaller than 100 % has to be applied for the current outputs in order to prevent a protective
shut-down of the current amplifier by the overtemperature protection function (→
Duty cycles on
page 23). If the CMC 430 performed a protective shut-down of the current amplifier, an according
message is displayed in the controlling software or at the controlling device.
You can then try the following to avoid further protective shut-downs:
• Use shorter duty cycles, for example, 50 % ON-time instead of 75 %.
• Reduce the compliance voltage of the current outputs. This way, you can optimize the output
power limit of the current amplifiers.
• Use the CMC 430 at lower ambient temperatures.
Refer to the figures shown in section Duty cycles on page 23 for typical duty cycles for different
ambient temperatures.
Refer to the documentation of the controlling software or device for detailed information on how to set
the compliance voltage.
Troubleshooting
OMICRON 49