When the necessity arises for the reliable detection and warnings against smoke and heat our multi-sensor smoke and heat detectors should be your first choice. The two asynchronously work well to ensure minimal false alarm feedback.
There are two types of heat detection methods:
Fixed temperature detectors rely on the mixture of two or more metals combined known as eutectic alloy.
This alloy because of its mixture has a low melting point. When ambient temperature reaches the eutectic temperature the alloy changes from a solid to a liquid.
Fixed temperature detectors can also operate using a single thermistor a type of resistor whose resistance is dramatically affected by temperature to effectively
detect changes in ambient temperatures.
Rate-of-rise temperature detectors most commonly make use of thermistors known as thermocouples to distinguish change in ambient temperatures. A thermistor is a type of resistor whose resistance is dramatically affected by temperature. A rate-of-rise detector can have one or two thermistors – one for monitoring heat radiation and the other for monitoring ambient temperature. When a rise in heat is identified the rate of the risen temperature is calculated by the thermistor responsible for the ambient temperature and compared to the thermistor responsible for the heat radiation. If a rate of 1.6°C per minute is picked up the detector is triggered.
An optical smoke detector also known as a photoelectric alarm is a light sensor. The optical smoke detector uses a photodiode (sensor) and an infrared LED to detect smoke inside a chamber built into the device known as an optical chamber. The sensor inside the chamber is placed across the infrared LED to an angle so that the LED beam does not point directly at the photodiode. When smoke enters the chamber the LED beam reflects off small particles of smoke and directs it to the sensor thus triggering the alarm.
Make sure the detector is functioning properly before installing it. The detector should be placed as close as possible to the centre of the ceiling. If ceiling mounting is not possible then the detector can be wall mounted 30 cm from the ceiling.
The multi sensor uses the same algorithm in the Orbis optical detector to reduce false alarm feedback. It just goes a step further and makes use of an added in heat detector (thermal) panel that senses fast burning or flaming fires.
This is the detector of choice for any high risk areas of fire where an electric power cable is present or where a security system is installed or capable of being installed.
The Discovery multi sensor makes use of optical technology to detect smoke and uses a temperature detector called a thermistor that is used to detect temperatures with greater precision but only within a limited temperature range of −90 °C to 130 °C. The detector can rely on the combination of both signals to achieve a final result.
Discovery multi sensor detectors can be used in a wide range of environments such as bedrooms, offices, medium sized buildings, large homes or restaurants where an electric power cable or fire security system is present or capable of being installed.
The XP95 is similar to the Discovery multi-sensor detector and uses optical technology to detect smoke particles. Combined with its heat detector the XP95 relies on the combination of the two outputs (smoke and heat) to give a final analogue value.
XP95 multi sensor detectors can be used in a wide range of environments such as bedrooms, offices, medium sized buildings, large homes or restaurants where an electric power cable or fire security system is present or capable of being installed.