In normal AC operation the Power Sentry battery is being charged, the battery at this time is not operating any of the lamps. The regular AC ballast is powered by the switched HOT feed. The regular AC ballast neutral feed is passes through a Normally Closed Replay and then out to the regular AC ballast on the White/Red wire, which the regular AC ballast neutral wire is connected to. At this time the following events are occurring in Normal AC Operation:
- The AC ballast is energized and the lamps in the luminaire are illuminated.
- The Battery is being charged by the constant HOT line feed.
- The Test Switch/Pilot Light is lit at the this time to indicate that the battery is receiving AC power for battery charging.
In Emergency Operation the Power Sentry battery is operating the lamp(s), this occurs when there is a loss of power to the constant power feed to the Power Sentry battery pack, the regular AC ballast will have also lost its power feed from the swithed HOT feed. The regular AC ballast neutral feed is removed from the ballast when ballast output to the lamp is also now opened. The Normally Open Relay contacts are now closed which connects the battery to the lamp(s) which will be operated for 90 minutes from the battery. The return path to the battery is via the RED wire which is connected to the opposite end of the lamp(s) being operated. At this time following events are occurring in Emergency operation:
- Constant HOT feed to the battery is OFF the battery turns ON to operate the lamp wired for Emergency operation and the Test Switch/Pilot Light is OFF.
- Regular ballast neutral feed is lost as relay is now OPEN as is the relay that connects the ballast lamp output to the lamp.
- Battery powers lamp for minimum of 90 minutes, after regular AC power is restored battery will be recharged.