Danfoss VLT FC 103, Service Manual

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6. Remove two screws (T30) from the bottom of the
brake IGBT module.
7. Remove one thread-forming retaining screw
(T25).
8. Remove four screws (T25), one from each corner
of the IGBT module.
For reassembly, follow the replacement IGBT instructions.
7.3.18 IGBTs
7.3.18.1 400 V AC Power Size
1. Remove the gate drive card in accordance with
chapter 7.3.14 IGBT Gate Drive Card .
2. Remove the SCR input bus bars in accordance
with
chapter 7.3.15 SCR Input Bus Bars .
3. Remove the balance/high frequency card in
accordance with
chapter 7.3.11 Balance/High
Frequency Card .
4. Remove the Mylar cover from the capacitor bank.
5. Remove the round bus bar support bracket by
removing three screws (T30).
6. Remove one screw (T25 thread-forming) from
each IGBT output bus bar, one bus bar per IGBT
module.
7. Remove the IGBT output bus bar by removing
two screws (T30), from each IGBT output bus bar,
one bus bar per IGBT module.
8. Remove the IGBT temperature cable by discon-
necting the cable from each IGBT module.
9. Remove the gate leads, one from each IGBT
module.
10. Remove the snubber capacitor from each IGBT
module by removing the two screws (T30)
mounting the capacitor to the IGBT module.
11. Remove the (-) DC plate by removing:
•
Three screws (T20 thread-forming), next
to the IGBT modules
•
One standoff (0.3 in [8 mm]) connecting
the plate to the negative terminal of
capacitor 3
•
Screws (T25) connecting the plate to the
negative terminals of capacitors 4 and 5.
Number of T25 screws varies based on
the size of the adjustable frequency
drive.
12. Remove the Mylar insulator between the (-) DC
plate and the (+) DC and DC center capacitor
plate. The screws connecting the (+) DC and DC
center plates to the capacitors may have to be
removed to remove the insulator.
13. Remove the (+) DC plate by removing:
•
Three screws (T20 thread-forming) next
to the IGBT modules
•
One standoff (0.3 in [8 mm]) connecting
the plate to the positive terminal of
capacitor 2
•
Screws (T25) connecting the plate to the
positive terminals of capacitors 1 and 6.
Number of T25 screws varies based on
the size of the adjustable frequency
drive
14. Remove the plastic IGBT support (not shown) by
removing four screws (T25).
15. Remove the IGBTs by removing four screws (T25)
from each.
For reassembly, use the replacement IGBT instructions.
See Figure 7.7
7.3.18.2 690 V AC Power Size
1. Remove the gate drive card in accordance with
chapter 7.3.14 IGBT Gate Drive Card .
2. Remove the SCR input bus bars in accordance
with
chapter 7.3.15 SCR Input Bus Bars .
3. Remove the balance/high frequency card in
accordance with
chapter 7.3.11 Balance/High
Frequency Card .
4. Remove the Mylar cover from the capacitor bank.
5. Remove the round bus bar support bracket by
removing three screws (T30).
6. Remove one screw (T25 thread-forming) from
each IGBT output bus bar, one bus bar per IGBT
module.
7. Remove the IGBT output bus bar by removing
two screws (T30) from each IGBT output bus bar,
one bus bar per IGBT module.
8. Remove the IGBT temperature cable by discon-
necting the cable from each IGBT module.
9. Remove the gate leads, one from each IGBT.
Disassembly and Assembly In... Service Manual
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