Danfoss VLT FC Series, Service Manual

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11.2.20 Standard DC Capacitors
To remove or reinstall the standard DC capacitors, use the
following steps.
NOTICE
CAPACITOR REPLACEMENT
When replacing DC capacitors, always replace the entire
bank of capacitors, even if only 1 DC capacitor has failed.
NOTICE
CAPACITOR TYPE
Drives can contain standard DC capacitors or twistlock
capacitors. Use the standard DC capacitor instructions for
drives manufactured prior to the following time period:
•
240/400 V AC units produced before week 18,
2018.
•
690 V AC units produced before week 23, 2018.
For excluded drives, see chapter 11.2.22 Twistlock DC
Capacitors .
Disassembly in 400 V AC units
To remove the standard DC capacitors from 400 V DC
units, use the following steps. Refer to
Illustration 11.14 .
1. Remove the gate drive card. Refer to
chapter 11.2.14 Gate Drive Card .
2. Remove the balance/high frequency card. Refer to
chapter 11.2.13 Balance/High Frequency Card .
3. Remove the DC bus rails. Refer to
chapter 11.2.18 DC Bus Rails .
4. Remove the insulator sheet from the capacitor
bank.
5. Remove the IGBT output busbars by removing 3
thread-forming screws (T20), 1 per busbar, and 6
screws (T40), 2 per busbar.
6. Remove the snubber capacitors, 1 from each IGBT
module, by removing 2 screws (T40).
7. Remove the DC(+) plate by removing:
7a The standoff (8 mm) connecting the
plate to the positive terminal of
capacitor 3.
7b Screws (T25) connecting the plate to the
positive terminals of capacitors 1, 2, 4, 9,
and 12. The number of T25 screws
varies based on the size of the drive.
8. Remove the insulator between the DC(+) plate
and the DC(-) plate. If necessary, first remove the
screws connecting the DC(-) plate and the DC
center plate to the capacitors.
9. Remove the DC(-) plate by removing:
9a The standoff (8 mm) connecting the
plate to the negative terminal of
capacitor 6.
9b Screws (T25) connecting the plate to the
negative terminals of capacitors 5, 7, 8,
10, and 11. The number of T25 screws
varies based on the size of the drive.
10. Remove the insulator sheet between the DC(-)
plate and the DC center plate. If necessary, first
remove the screws connecting the DC center
plate to the capacitors.
11. Remove the DC center plate by removing:
11a The standoff (8 mm) connecting the
plate to the negative terminal of
capacitor 2.
11b Screws (T25) connecting the plate to the
negative terminal of capacitors 1, 3, 4, 9,
and 12.
11c Screws (T25) connecting the plate to the
positive terminal of capacitors 5, 6, 7, 8,
10, and 11. The number of screws (T25)
varies based on the size of the drive.
12. Remove the capacitor locking panel by removing
the 10 thread-forming screws (T25).
Reassembly in 400 V AC units
Reinstall in reverse order of this procedure. Tighten
hardware according to
chapter 14.1 Fastener Torque Ratings .
D2h/D4h/D7h/D8h/J9 Unit Dis...
VLT
®
FC Series, D1h–D8h, Da2/Db2/Da4/Db4, E1h–E4h, J8/J9
216 Danfoss A/S © 02/2019 All rights reserved. MG94A502
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