Given: A storage battery supply back-up power for a local protective premises signaling system shall be properly recharged after use. If the battery is recharged from the circuit that cannot be switched on or off, recharging shall be done within how many hours?

Given: A storage battery supply back-up power for a local protective premises signaling system shall be properly recharged after use. If the battery is recharged from the circuit that cannot be switched on or off, recharging shall be done within how many hours?