Danfoss Turbocor TT Series Service Manual page 231

1. Isolate compressor power.
2. Remove the Service Side Cover. Refer to Section 4.1.3.1 S ervice Side Cover Removal and Installation on
3. Wait for the LEDs on the Backplane to turn off.
4. Remove the Serial Driver, BMCC, and PWM.
5. Set multimeter for resistance checks.
6. Test resistance on bearing power feedthrough pins defined in Table 4-45 M agnetic Bearing Coil
Use care not to damage the pins when inserting test leads into the connectors.
7. Compare the resistance values to those defined in Table 4-45 M agnetic Bearing Coil Resistance Values.
8. Test insulation of each pin to ground and between coils.
9. If the integrity of the bearing power feedthrough is in question, isolate the compressor, recover the
Table 4-45 Magnetic Bearing Coil Resistance Values
Connector Bearing
Location Identification
Rear Radial Coil
Rear Bearing
Connector
Axial Coil
Front B earing
Front Radial Coil
Connector
Refer to Figure 4-256 F ront and Rear
Notes Bearing Feedthrough Connectors for pin
locations
Figure 4-256 Front and Rear Bearing Feedthrough Connectors
page 54.
Resistance Values. Refer to Figure 4-256 F ront and Rear Bearing Feedthrough Connectors for pin
locations.
• • • CAUTION • • •
refrigerant according to industry standards, remove the feedthrough and repeat the above steps
directly at the internal bearing cluster block.
Compressor Model & Design Sequence
Feedthrough
TTS300, TTS400, TGS230,
Pin
Identification
1 & 6 2.70 - 3.25Ω
2 & 5 2.70 - 3.25Ω
5.70 - 6.20Ω (TTS300/TGS230 only)
3 & 4
6.00 - 6.70Ω (TTS400/TGS390 only)
1 & 2 2.70 - 3.25Ω
3 & 4 2.70 - 3.25Ω
All resistance values are in ohms. Resistance to ground and between coils should be >100MΩ
@1KV
TTS350, TTS450, TTS500, TTS700, TGS310,
TGS380, TGH490, TGS520, TTH375, &
& TGS390
2.70 - 3.25Ω
2.70 - 3.25Ω
6.00 - 6.70Ω
4.70 - 5.20Ω
4.70 - 5.20Ω
M-SV-001-EN Rev. H-1/23/2023 Page 231 of 294
TGH285