Patent ID: 9117360
Filing Date: 2015-08-25
Classification: G08B

Abstract:
1. A low battery trouble signal delay circuit for a smoke detector configured for periodically measuring environmental conditions and for producing a fire alarm signal when smoke is detected in the environment, said trouble signal delay circuit comprising: a battery; a comparator configured for receiving a voltage measurement signal from the battery and a reference voltage measurement signal and sending a resulting signal to an activator circuit; at least one activator in said activator circuit that is user activated upon receiving a first input; at least one low battery trouble signal annunciator connected to the activator circuit and configured for indicating that the voltage measurement signal is below the reference voltage measurement after receiving a signal from the comparator; and a lockout device connected to the activator circuit for temporarily preventing reactivation of the activator after the activation, wherein the activator temporarily disables the low battery trouble signal when activated for a predetermined silencing time period, while maintaining the operation of the fire alarm signal, and the activator circuit automatically enables the low battery trouble signal at the end of the predetermined silencing time period.