What signal is received when the fire alarm system is placed in a bypass or test mode?

When the fire alarm system is placed in a bypass or test mode, a "trouble" signal is typically received. This is because the bypass or test mode indicates that the system is not operating in its normal alarm monitoring capacity. It may be temporarily disabling certain devices to allow for maintenance or testing without triggering a full alarm response.

In this context, the trouble signal serves as a notification that the system is not fully operational, alerting personnel that they need to be aware of the modified state of the system. This is crucial for maintaining safety and awareness during maintenance activities. The receiving of a trouble signal helps ensure that any issues can be addressed immediately upon returning the system to its normal operational state.