Alarms for testing sensors, particularly those used in fire-suppression systems, are described. In one aspect of the invention, the alarm includes an audio and/or a visual indicator operably coupled to the housing of a sensor. The audio indicator may be a speaker that beeps when the sensor is activated. The visual indicator may be one or more LEDs that are illuminated when the sensor is activated. The alarm also can be used to determine whether power and ground conductors extending to the sensor are properly connected. Additionally, the alarm can be used to determine whether one or more conductors extending from the sensor to the control panel are properly connected.