Danfoss Turbocor TTS Series Service Manual page 275

Figure B-24 Compressor Voltage Troubleshooting Flowchart (Sheet 3)
B
Electrically isolate
compressor – Refer
to Electrical Isolation
1.7
Remove Top Cover
Remove DC Bus Test
Harness and re‐
install the J2 and J3
outputs to DC‐DC
Re‐install Top Cover
and remove Service
Side Cover
Re‐apply mains
power
Verify the HV+ and
24VDC test points
on Backplane
Both voltages
within +/‐ 10%?
Yes
No
Electrically isolate
compressor
Remove all
connectors from
Backplane, leaving
only the J6 (IGBT
cable), J4 (250VDC),
and J24(VDC) inputs
connected
Remove Serial
Driver, BMCC, and
PWM
Re‐apply mains
power
Verify the HV+ and
24V test points on
Backplane
Are voltages
Yes
within +/‐ 10%?
No
Replace DC‐DC
Verify the +17V +5
and the ‐15 and +15
voltage and
resistance values
Replace Backplane
Are all voltages
No
within +/‐ 10%?
Yes
Electrically isolate
compressor
End
Re‐install all
connectors and the
PWM, BMCC and
Serial Driver to
Backplane
Re‐apply
compressor power
Verify the +17V,
+15V, +5 and ‐15
voltages
Are all voltages
No
within +/_ 10%?
Yes
If any of the voltages
are not within +/‐
10% refer to Section
5.5.2 "Determine
the Cause of an
Energy Drain."
M-SV-001-EN Rev. G
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