Danfoss VLT 5000-P User Manual

5-8
VLT is a registered Danfoss trademark
5.1.4 Soft Charge Rectifier Test: E-frame Size
The DC cable at connector MK3 remains disconnected for
this procedure.
Since the rectifier test requires the soft charge resistor to be in
the circuit, verify the resistor is good before proceeding.
1. Measure resistance between pins A and B of
connector MK4 on soft charge card. It should
read 27 ohms (±10%) for 380-500 V drives or 68
ohms (±10%) for 525-690 V drives. A reading
outside this range indicates a defective soft
charge resistor. Replace resistor in accordance
with disassembly procedures in Section 7.
Continue tests.
Should the resistor be defective and a replacement not readily
available, the remainder of the tests can be carried out by
disconnecting the cable at connector MK4 on the soft charge
card and placing a temporary jumper across pins A and B.
This provides a path for continuity for the remaining tests. Ensure
any temporary jumpers are removed at the conclusion of the
tests.
For the following tests, set the meter to diode check or Rx100
scale.
2. Connect negative (-) meter lead to positive (+)
MK3 (A) (DC output to DC bus), and connect
positive (+) meter lead to MK1 terminals R, S,
and T in turn. Each reading should show a diode
drop.
3. Reverse meter leads with positive (+) meter lead
to positive (+) MK3 (A). Connect negative (-) lead
to MK1 terminals R, S, and T in turn. Each
reading should show open.
Figure 5-5. Soft Charge Card Connectors
MK1
MK2
MK4
MK3
4. Connect positive (+) meter lead to negative (-)
MK3 (C). Connect negative (-) meter lead to
MK1 terminals R, S, and T in turn. Each reading
should show a diode drop.
5. Reverse meter leads with negative (-) meter lead
to negative (-) MK3 (C). Connect positive (+)
meter lead to MK1 terminals R, S, and T in turn.
Each reading should show open.
An incorrect reading here indicates the soft charge rectifier is
faulty. The rectifier is not serviced as a component. Replace
the entire soft charge card in accordance with the disassembly
procedures in Section 7.
Reconnect MK3 on shoft charge card after these tests.

Danfoss VLT 5000-P Specifications

General

Brand	Danfoss
Model	VLT 5000-P
Category	DC Drives
Language	English