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If the desired signal is not present in the display, the
problem may be either in the external control wiring to
the drive or a faulty control card. To determine the fault
location, use a volt meter to test for voltage at the control
terminals.
Verify the control voltage power supply is correct as
follows.
1.
With a voltmeter measure voltage at control card
terminal 12 and 13 with respect to terminal 20.
Meter should read between 21 and 27 VDC.
If the 24 V supply voltage is not present, conduct the
Control Card Test (6.3.17) later in this section.
If the 24 V is present proceed with checking the individual
inputs as follows
2.
Connect (-) negative meter lead to reference
terminal 20.
3.
Connect (+) positive meter lead to terminals 16,
17, 18, 19, 27, 29, 32, and 33 in turn.
Presence of a signal at the desired terminal should
correspond to the digital input display reading. A reading
of 24 VDC indicates the presence of a signal. A reading of
0 VDC indicates no signal is present.
Analog inputs
The value of signals on analog input terminals 53, 54, and
60 can also be displayed.
The voltage on terminals 53 and 54, or the current in
milliamps for terminal 60 is shown in line 2 of the display.
If the desired signal is not present in the display, the
problem may be either in the external control wiring to
the drive or a faulty control card. To determine the fault
location, use a volt meter to test for a signal at the control
terminals.
Verify the reference voltage power supply is correct as
follows.
1.
With a voltmeter measure voltage at control card
terminal 50 with respect to terminal 55. Meter
should read between 9.2 and 11.2 VDC.
If the 10 V supply voltage is not present, conduct the
Control Card Voltage Test earlier in this section.
If the 10 volts is present proceed with checking the
individual inputs as follows.
2.
Connect (-) negative meter lead to reference
terminal 55.
3.
Connect (+) positive meter lead to desired
terminal 53, 54 or 60.
For analog input terminals 53 and 54, a DC voltage
between 0 and +10 VDC should be read to match the
analog signal being sent to the drive.
For analog input terminal 60, a reading of 0.9 to 4.8 VDC
corresponds to a 4 to 20ma signal.
Note that a (-) minus sign preceding any reading above
indicates a reversed polarity. In this case, reverse the
wiring to the analog terminals.
6.4 Module-level Static Test Procedures
6.4.1 Inverter Module
Heatsink Temperature Sensor Test
Remove the inverter module from the drive in accordance
with disassembly procedures.
Test Procedures
High Power Service Manual for Modular F Frame Drives
MG90K202 - VLT
®
is a registered Danfoss trademark
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