Rectifier Module
1.
Unplug the 8-pin connector from the top of the
Rectifier Module. Read the terminals on the
Rectifier Module side of the connector (female
connector).
2.
Measure between pins 1 and 4. Should read
approximately 21
Ω
.
Inverter Module
1.
Unplug the 10-pin connector from the top of
each Inverter Module. Read the terminals on the
Inverter Module side of the connector (female
connector).
2.
Measure between pins 5 and 10. Should read
approximately 21
Ω
.
Incorrect Reading
An incorrect reading would indicate either a defective heat
sink fan or defective wiring to the fan.
Follow the instructions for removing the heat sink fan.
Make the following measurements on the connector
leading to the fan
1.
Measure between pins 1 and 2. Should read
approximately 21
Ω
.
2.
Measure between pins 1 and 3. Should read
approximately 45
Ω
.
3.
Measure between pins 2 and 3. Should read
approximately 68
Ω
.
4.
Measure between pins 1 and 4. Should read
open.
5.
Measure between pins 2 and 4. Should read
open.
6.
Measure between pins 3 and 4. Should read
open.
Incorrect reading
An incorrect reading indicates a failed fan. Replace the fan.
If the fan is OK, the problem is the wire harness inside the
module. Remove the module in question and replace the
fan wire harness.
Check 7: Option Cabinet Door Fan (only F3/F4)
This checks the wiring between the Rectifier Module and
the Option Cabinet Door Fan.
1.
Unplug the 8-pin connector from the top of the
Rectifier Module. Read the terminals on the wire
harness side of the connector (male connector).
2.
Measure between pins 5 and 8. Should read
approximately 47
Ω
.
Incorrect reading
In incorrect reading could indicate a failed fan or a bad
wire harness. Measure the fan resistance at the Option
Cabinet Door Fan. If bad, replace the door fan. If good,
replace the wire harness.
Reconnect the 8-pin connector on top of the Rectifier
Module.
6.3 Dynamic Test Procedures
6.3.1 Split Bus Mode
Powering the drive in the split bus mode allows dynamic
testing on the drive in a safer manner.
In the split bus mode, the DC bus in each module is split
into two portions. One connects to the DC bus and power
card to provide low voltage power for the SMPS. By
powering only the SMPS in each module, the various logic
circuits can be tested without the danger of damaging the
power components.
The other provides low voltage power to the DC capacitors
and the output IGBTs for test purposes. A low voltage
power supply connected to the DC bus allows testing the
functionality of the output section safely.
The following procedure will be referred to throughout the
dynamic test section.
Powering the Drive in Split Bus Mode
1.
Ensure that AC power has been removed and
that all DC capacitors are fully discharged.
2.
Remove the top and bottom safety covers from
each inverter module as well as the top safety
cover from the rectifier module.
3.
If a motor is connected to the drive, remove all
output bus bars from each inverter module. Also
remove the brake bus bars if the drive is
equipped with the brake option.
4.
Remove the plugs from the 6-pin sockets on each
module.
5.
Connect the power supply cable (p/n 176F8766)
to the 6-pin sockets of each module.
6.
Connect a 610 – 800VDC power supply to the
input end of the power supply cable.
7.
Apply power to the power supply. The LCP
should light up as if the drive were powered
normally.
8.
Warning 24,
External Fan Failure
will be displayed
in the LCP. This is because the fan circuitry is not
powered in this mode. This will not affect the
operation.
Test Procedures
High Power Service Manual for Modular F Frame Drives
94
MG90K202 - VLT
®
is a registered Danfoss trademark
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