6.3.5 Current Sensors Test CT1, CT2, CT3
For this procedure, provide 650 V using the split-bus
power supply.
Testing current feedback with the signal test board.
1.
Remove power to filter. Make sure the DC bus is
fully discharged.
2.
Install the signal test board into power card
connector MK104.
3.
Apply power to the filter with the 650 V split-bus
power supply.
4.
Using a DVM, connect the negative (-) meter lead
to terminal 4 (common) of the signal test board.
5.
Measure the AC voltage at terminals 1, 2, and 3
of the signal test board in sequence. These
terminals correspond with current sensors CT1,
CT2, and CT3, respectively. Expect a reading near
zero volts but no greater than +/-15 mV.
A reading of greater than 15 mVv suggests that the
corresponding current sensor be replaced.
6.3.6 Input Terminal Signal Tests
The presence of signals on either the digital or analog
input terminals of the filter can be verified on the filter
display. Digital or analog input status can be selected or
read in parameters 16-60 through 16-64.
Digital inputs
With digital inputs displayed, control terminals 18, 19, 27,
29, 32, and 33 are shown left to right, with a 1 indicating
the presence of a signal.
Figure 6.4
If the desired signal is not present in the display, the
problem may be either in the external control wiring to
the filter or a faulty control card. To determine the fault
location, use a voltmeter 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.
The meter should read between 21 and 27 V DC.
If the 24 V supply voltage is not present, replace the
control card.
If 24 V is present, proceed with checking the individual
inputs as follows
2.
Connect the (-) negative meter lead to reference
terminal 20.
3.
Connect the (+) positive meter lead to the
terminals in sequence.
The presence of a signal at the desired terminal should
correspond to the digital input display readout. A reading
of 24 V DC indicates the presence of a signal. A reading of
0 V DC indicates no signal is present.
Analog inputs
The value of signals on analog input terminals 53 and 54
can also be displayed. The voltage or current in mA,
depending on the switch setting, is shown in line 2 of the
display.
Figure 6.5
If the desired signal is not present in the display, the
problem may be either in the external control wiring to
the filter or a faulty control card. To determine the fault
location, use a voltmeter to test for a signal at the control
terminals.
Verify the reference voltage power supply is correct as
follows.
1.
With a voltmeter, measure the voltage at control
card terminal 50 with respect to terminal 55. The
meter should read between 9.2 and 11.2 V DC.
If the 10 V supply voltage is not present, conduct
Control Card Basic Voltage Test
earlier in this section.
Test Procedures
VLT Advanced Active Filter AAF006 D and E Frames Service Manual
MG90Z122 - VLT
®
is a registered Danfoss trademark
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