Chapter Five
5 - 2
Safety Warning
Maintenance work should be undertaken only by qualified personnel who are fully aware
of the danger involved and who have taken adequate safety precautions.
Always isolate all the supplies to the equipment before inspecting, moving equipment,
removing or replacing parts.
Work on the equipment while the electrical supplies are connected is not normally
necessary. If it should become necessary for any reason, take extreme care not to come in
to contact with live parts.
You should remain alert at all times when the unit is in operation. There are three main
sources of danger:
Electricity can kill.
Serious injury or death could result from contact with electrically live
parts. Even though the connections to the load bank may be temporary, they must always
be made to the same standards as if they were permanent.
Load banks contain fast moving parts.
The fan, in particular, can cause serious injury if
you come into contact with it when it is in operation.
Load banks produce a lot of heat.
When a test is in progress the resistive element can
glow cherry red. The heat they produce is removed by the air that the fan forces past them,
but that air in turn can become very hot.
Maintenance & Troubleshooting
5 - 3
Routine Maintenance Procedures
To keep the load bank in good working order, carry out the following maintenance tasks at
the specified intervals:
Daily (after transportation or before each use of the load bank):
•
Inspect the equipment for signs of damage.
•
Ensure that the inlet and outlet grilles are free from dirt, debris or obstruction. Remove
the grilles and clean them if necessary.
•
Check that both the external supply and the Supply-on-Test are properly connected.
•
Check that the connecting cables are free from damage.
•
Check that all cables are secured and routed so that they do not present a safety
hazard.
•
Ensure all panels are secure.
Monthly
•
Clean and inspect painted surfaces for damage or corrosion and touch up as necessary.
•
Check that there is no build up of dirt or debris on the load elements.
•
Check that the fan rotates freely.
•
Isolate the supply and then inspect the resistive load element terminals, ensuring that
they are tight and show no signs of overheating.
•
Visually inspect the switchgear cabinets, wiring, fuses and contactors for signs of
overheating.
•
Visually inspect and clean all filters.
In addition, carry out a load check to ensure that load contactors and elements are
operating correctly:
1. Connect a supply (at the load bank’s rated voltage) to the load bank.
2. Set and apply loads at 30%, 60%, and 100%, and make a note of the power value shown
on the instrumentation (or external metering).
3. Check that the power values are within 5% of the load set on the controller.
Annually
Verify the load bank instrumentation’s calibration. If adjustment is required contact ASCO
for advice.
Warning! The fan can
cause serious injury
when it is in operation.
Ensure that the supply
is isolated before re-
moving safety covers.
Note:
The recommend-
ed interval for a calibra-
tion check is one year,
unless the equipment
has been subject to
misuse or damage.
