Control for fire fighting equipment - uses tripping signal working with time lag element producing signal with delay shorter than alert time

摘要

The fire fighting installation has room mounted fire alarms with control circuit assigned to certain sections. The control circuit produces an operating signal after an alert time has elapsed. The trip signal is fed into a time lag element which produces an output signal. The output signal is produced after a time lag which is shorter than the alert time. The supply line is fitted with a switch operated by the output signal of the time lag element. The switch is fitted with a protection with a tripping current, which is larger than the holding current.