APC VS 50 - Manual (Page 52)

Magnum VS –48 Vdc User’s Manual Page 47
7 Preventive Maintenance
Preventive Maintenance is typically performed on a quarterly basis.
7.1. Equipment
1. 4 Digit voltmeter.
2. Clamp-on ampere meter.
3. Standard Insulated tools.
7.2. Inspection
Environmental Inspection
1. Ensure the dc system environment is suitable for operation.
2. Ensure that there is sufficient clearance around the system for service.
3. Ensure that there is no sign of damage to the dc system.
4. Contact monitoring personnel or disable system alarms before servicing the unit. This
will allow the unit to be serviced without creating false alarms.
System Visual and Safety Inspection
WARNING: Hazardous energy levels are present on bare conductors in the
dc distribution connection area of the plant. Accidental shorting of distribution
conductors can cause arcing and high currents that can cause serious burns
or other physical harm. It is recommended that:
• Any jewelry, rings or watches be removed while working on this
equipment.
• Handles of all wrenches, screwdrivers, cutters and pliers are insulated.
1. Ensure that the dc wiring is properly installed, sized, terminated and identified.
2. Ensure that the ac wiring is properly installed, sized, terminated and identified.
3. Ensure that the battery wiring is properly connected to the System.
4. Ensure that the dc output over-current protection devices are adequate for the size of
wiring installed.
5. Ensure that the dc Positive is bonded to central office ground (- 48 volt system).
6. Note the resistance of the ground bond.
7. Note any currents flowing in the ground.
8. Record ambient temperature.
9. Verify that the battery polarity is correct.
10. If battery disconnect devices are present, note the following for each device:
a) DC voltage rating.
b) DC current rating