The Apollo XP95 55000-885APO is a multisensor detector, with an optical smoke sensor and a thermistor temperature sensor. The outputs of the sensors are combined to give the final analogue value. The construction of the Apollo XP95 55000-885APO is similar to that of the optical smoke detectors, but uses a different lid and optical mouldings to accommodate the thermistor temperature sensor.
The signals from the optical smoke sensing element and the temperature sensor are independent, and represent the smoke level and the air temperature respectively in the vicinity of the 55000-885APO. The microcontroller inside the XP95 55000-885APO processes the two signals. The temperature signal processing extracts only rate-of-rise information for combination with the optical signal. The XP95 55000-885APO does not respond to a slow temperature increase, even if the temperature reaches a high level. When a large sudden change in temperature is sustained for 20 seconds, the 55000-885APO causes an alarm without the precense of smoke.
The processing algorithms in the 55000-885APO incorporates drift compensation. The control panel must not have a drift compensation algorithm enabled. The sensitivity of the XP95 55000-885APO is considered the optimum for most general applications since it offers good response to both smouldering and flaming fires.
