1
5
4
3
2
130BX184.10
Figure 6.3 Fan and DC Bus Fuse Locations
1
Power card
4
Mounting plate
2
DC bus fuse
5
MK107
3
Fan fuse
Table 6.2
6.2.6 AC Line power Contactor and Soft
Charge Contactor Tests
The AC line power contactor and soft charge contactor can
be tested for continuity using an ohmmeter set to Rx1
scale.
Measure resistance across each set of contacts in both the
energized and non-energized state.
1.
Place meter leads across the contact sets (L1 –
T1, L2 – T2, L3 – T3) in turn. The non-energized
state should read open (infinite resistance).
2.
Repeat step 1 in the energized state.
NOTE!
In most cases, depressing the plunger on the top of the
contactor does not allow closing the contacts. The
energized state should read 0 (or near 0) Ω.
3.
Using meter leads, measure resistance across
each set of auxiliary contacts Aux 1 – Aux 2.
Reading values for the non-energized state
should be infinite resistance, and near 0 Ω for
energized state of the AC Line power contactor
and soft charge contactor.
NOTE!
The AC line power contactor and soft charge contactor
have an electronic coil, therefore using an ohmmeter to
test the coil by measuring the resistance across the coil is
not possible. In general, the ohmmeter should measure 1–
5 M Ω. Low values indicate on coil damaging.
6.3 Dynamic Test Procedures
NOTE!
Test procedures in this section are numbered for reference
only. Tests need not be performed in this order. Perform
tests only as necessary.
WARNING
Electrical Hazard
Never disconnect the input cabling to the filter with power
applied due to danger of severe injury or death.
CAUTION
Take all the necessary safety precautions for system start
up before applying power to the filter.
6.3.1 No Display Test
A filter with no display can be the result of several causes.
A single character in the display or a dot in the upper
corner of the display indicates a communication error and
is typically caused by an option card not being properly
installed. When this condition occurs, the green power-on
LED is illuminated.
If the LCD display is dark and the green power-on LED is
not lit, proceed with the following tests.
First test for proper input voltage.
6.3.2 Input Voltage Test
1.
Apply power to filter.
2.
Use the DVM to measure the input AC line
voltage between the filter input terminals in
sequence:
L1 to L2
L1 to L3
L2 to L3
All measurements must be within the range of 342–550 V
AC. Readings of less than 342 V AC indicate problems with
the input AC line voltage.
In addition to the actual voltage reading, the balance of
the voltage between the phases is also important. The
filter can operate within specifications as long as the
imbalance of the supply voltage is not more than 3%.
Test Procedures
VLT Advanced Active Filter AAF006 D and E Frames Service Manual
MG90Z122 - VLT
®
is a registered Danfoss trademark
6-5
6
6
