GE Giraffe OmniBed Service Manual page 75

Cause(s)
No output from heater
isolation transformer.
Defective relay board.
Defective heater
isolation transformer
Defective DAC circuit
on control board.
Defective solid state
relay (SSR)
Defective radiant
heater SSR
Defective incubator
heater SSR
Defective current sense
circuit on relay board.
Defective 50-pin ribbon
cable
© 2001 by Datex-Ohmeda, Inc.. All rights reserved.
Action(s)
In service mode, check the output voltage of the heater isolation transformer at the one
pin connectors on the black and white wires on the transformer secondary. This secondary
voltage should always read 115 volts.
• If 115 volts is present, then replace the relay board.
• If 115 volts is not present, check that the mains voltage is input to the transformer
primaries.
• Be sure J49 on the relay board is properly connected.
• Verify the configuration plug on the transformer primary is seated properly.
To measure primary input voltage on 115 volt units:
• Verify mains voltage is present at pins 2-5 (brown and orange wires) on the
transformer primary configuration plug.
• Verify mains voltage is present at pins 3-6 (yellow and blue wires) on the
transformer primary configuration plug
To measure primary input voltage on 230 volt units:
• Verify mains voltage is present at pins 2-6 (brown and blue wires) on the
transformer primary configuration plug.
• If voltages are not present, verify mains voltage is present at pins 1-4 (black and
red wires) on the transformer primary configuration plug.
• If not, replace the relay board.
If voltage is present at primaries but no voltage output at secondaries, replace the heater
isolation transformer.
If failure persists, replace control board. After replacing the control board, set it to incubator
mode and restart the unit.
Power up the unit in service mode. Run status test on the second service screen and verify
that the I/WHTROFF (incubator/warmer heater off) test fails. If the status test fails, then it is an
SSR problem. If the status test does not fail, then try the recommended action for a defective
current sense circuit on relay board, below.
To determine which SSR is shorted, disconnect an output wire from them one at a time and
rerun the status rest.
Disconnect the black wire (larger diameter) from the AC side of the radiant heater solid state
relay. Run status test. If I/WHTROFF test passes replace the radiant heater SSR. If it still fails
reconnect the wire to the SSR.
Disconnect the black wire (larger diameter) from the AC side of the incubator heater solid state
relay. Run status test. If I/WHTROFF test passes replace the incubator heater SSR. If it still fails
reconnect the wire to the SSR.
Replace relay board.
If failure persists, replace 50 pin ribbon cable.
Chapter 4: Troubleshooting
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