What capacity in amperes does a storage battery need to be in order to operate a 50 watt transmitter for 6 hours? Assume a continuous transmitter load of 70% of the key-locked demand of 40 A, and an emergency light load of 1.5 A.

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Multiple Choice

What capacity in amperes does a storage battery need to be in order to operate a 50 watt transmitter for 6 hours? Assume a continuous transmitter load of 70% of the key-locked demand of 40 A, and an emergency light load of 1.5 A.

The amount of battery capacity you need is found by multiplying the total current the system draws by the time it must run. The transmitter load is 70% of the 40 A demand, which is 28 A. The emergency lighting adds 1.5 A, giving a total load of 28 + 1.5 = 29.5 A. For 6 hours of operation, the battery must supply 29.5 A × 6 h = 177 Ah. So, a storage battery of at least 177 ampere-hours is required. In practice, you’d allow extra margin for inefficiencies and aging.

The amount of battery capacity you need is found by multiplying the total current the system draws by the time it must run. The transmitter load is 70% of the 40 A demand, which is 28 A. The emergency lighting adds 1.5 A, giving a total load of 28 + 1.5 = 29.5 A. For 6 hours of operation, the battery must supply 29.5 A × 6 h = 177 Ah. So, a storage battery of at least 177 ampere-hours is required. In practice, you’d allow extra margin for inefficiencies and aging.

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