Danfoss VLT Series Service Manual page 33

Rectifier Module:
1. Remove the five terminal screws from the module. Note the wire orientation
and disconnect all wire leads.
2. Remove the two mounting screws securing the rectifier module to the heatsink
and remove the module.
3. Clean the thermal grease from the enclosure heatsink and from underneath
the Rectifier Module.
4. Apply silicon grease 3 mils thick to the entire base of the Rectifier Module.
5. Install the module and alternately torque the screws to 19-21 LB-IN (2.2Nm).
6. Replace all wire leads to the Rectifier Module terminals and torque the
terminal hardware to 19-21 LB-IN (2.2 Nm).
IGBT Module:
1. Remove the HF Card (does not apply to 230V units).
2. Remove all hardware mounting the IGBT bus bars and the Clamp Capacitors.
3. Remove the remaining wire connecting the IGBT to the Motor Coil.
4. Remove the mounting screws on the IGBT and remove from the unit.
5. Clean the thermal grease from the enclosure heatsink and from underneath
the IGBT Module.
6. Prior to installing the IGBT module, apply silicon grease 3 mils thick to the
entire base of the module.
7. Install the module and lightly tighten the mounting screws. Tighten the
mounting screws to a final torque of 19-21 LB-IN (2.2Nm).
8. Re-install the IGBT bus bars, clamp capacitors and Motor Coil lead. The
IGBT terminal hardware (including the 7mm HF Card standoffs) should be
torqued to 27-29 LB-IN, (3.2 Nm).
9. Replace the HF Card and HF Card foil. The HF Card mounting screws should
be tighten down to 12-14 LB-IN, (1.5Nm)
Section Four
4 - 5