Figure 115 - Pwm Connector - 6 Pin; Figure 116 - Pwm Test Points - Danfoss Turbocor VTT Series Service Manual

Figure 115 - PWM Connector
- 6 Pin

Figure 116 - PWM Test Points

Compressor Components
Diode Test
1. Isolate the Compressor power as described in the
section of this manual.
2. Disconnect the PWM Bearing Power Cables from the Compressor bearing feed throughs.
3. Unplug the 250V DC input to the PWM.
4. Using a Multimeter, set to measure Diode, place the positive(+) test lead on the HV- test point of
the PWM and negative(-) lead in the first pin hole of the rear PWM Bearing Power Cable.
5. The measured voltage drop should be 0.33-0.46 VDC.
6. Repeat in a clockwise rotation for all the outer pin holes of the rear Bearing Power Cable and the
4 pins of the front Bearing Power Cable (The center pin of the rear Bearing Power Cable does not
have a test value.).
7. Place the negative (-) test lead on the HV+ test point of the PWM and the positive(+) lead in the
first pin hole of the PWM Bearing Power Cable.
8. Repeat in a clockwise rotation for all the outer pin holes of the rear Bearing Power Cable and the
4 pins of the front Bearing Power Cable. (The center pin of the rear Bearing Power Cable does
not have a test value.)
9. The measured voltage drop should be 0.33-0.46 VDC.
"Electrical Isolation of the Compressor/VFD"
Pin 1
TP 1: HV+
TP 3: 17VDC
TP 2: HV-
M-SV-VT-001-EN Rev. A
97 of 165