When the electrical system is healthy with generators online, what would you expect to see on the DC voltmeter and ammeter?

• A. The voltmeter at nominal system voltage (~28V) and the ammeter showing load current balanced by generation, with no excessive discharge.
• B. The voltmeter reads zero and the ammeter shows maximum discharge.
• C. The voltmeter reads high voltage while the ammeter shows large discharge.
• D. The voltmeter fluctuates and the ammeter shows no consistent load.

Answer: (A)

When the electrical system is healthy and the generators are online, the DC bus is kept at a nominal voltage, typically around 28 volts. The voltage regulator in the generators auto-regulates to hold that level, so the DC voltmeter should read roughly 28V. The DC ammeter shows the balance between what the loads draw and what the generators supply. If everything is functioning properly, generation meets demand, so there’s no significant discharge from the battery bank and no excessive current drawn from it. In short, you’ll see about 28V on the voltmeter and the ammeter indicating the load current being supplied by generation with no abnormal discharge.