bonitron M3460UC, Customer Reference Manual

Page: 35 / 56

User’s Manual
35
5.2.2. C
APACITOR
T
ESTING
P
ROCEDURE
1. Open the panel door to expose the capacitor bank.
1. Measure voltage across each cap and make note for future reference.
2. Any voltage difference more than 15% indicates a substantial change in
capacitance.
Example: DC bus = 540V, each series cap = 270V
15% of 270 = 40.5V
cap 1 = 290V
cap 2 = 250V
Turn off power, discharge the capacitor bank voltage and replace both
capacitors if the difference is more than 15%.
5.2.3. C
LEANING
It may be necessary to clean off dust, debris, or chemical build-up on high
voltage bus bars or other exposed components. If cleaning is needed:
•
Remove power and allow all voltages to drain.
•
Check for residual voltages with meter.
•
Clean affected areas with rag, brush or denatured alcohol, depending on
the type of contamination.
•
Once area is clean and dry, reapply power.
5.2.4. H
EATSINKS
Dirt can build up on heatsink surfaces degrading its ability to dissipate heat.
The heatsinks should be checked for large amounts of deposits and cleaned
as needed. The maintenance interval depends upon the amount of activity and
the environment inside the cabinet.
Checking the heatsink should be included when checking for fan operation.