Electrical Safety Checks - Siemens VersiCharge Ultra 175 Maintenance Manual

Electrical safety checks

It is recommended to complete the following checklist annually.
1. Check the protective earth connections (around enclosure) for:
• breakage or loss
• signs of corrosion
2. Measure the resistance of the main, protective earth connection.
3. Inspect connections to buried earth electrode for signs of:
• corrosion
• breakage
• loss
4. Inspect all buried site cables interconnecting the equipment for signs of insulation degradation.
5. Check any insulating supporters and insulators for condition and fit.
6. Check all connections and visible components for signs of overheating (especially IPU contactors and main power
connections).
7. Check cable support/strain relief structures.
8. Retorque any screw terminals (especially contactor).
9. Inspect the retention of rectifier module screw terminals (these cannot be retorqued).
10. Check the resistance of 50 Ohm discharge resistor and 25 Ohm discharge resistor (can be done with a DMM with the
power off).
11. Retorque and check IMD connections and terminals.
12. Check AC contactors in the IPU are in the released/open position when de-energized (this can be visually checked with the
power off).
13. Visual inspection of SPD devices and associated fuses in the IPU.
14. Evaluate the amount of deposited pollution visible in the enclosure. Consider cleaning as necessary.
15. Manually engage all ten Power Unit contactors and listen for chatter or intermittent operation.
16. Check isolation transformer primary / secondary connections for corrosion or heating.
Maintenance Manual | VersiCharge Ultra 175™
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