HOCHIKI ACA-V Analog Multi-Criteria Sensor
The HOCHIKI America ACA-V Multi-Criteria Smoke Sensor is particularly suited for detecting smoke produced by a wide range of combustibles found in various applications. Temperature monitoring is achieved by a thermistor placed for optimum sensitivity. Hochiki’s unique design allows fast response to flaming fires as well as smoldering fires while minimizing false alarms.
STANDARD FEATURES • Low Profile – Only 2.23″ high, including base • Simple and reliable device addressing method • Automatic compensation for sensor contamination • Built-in fire test feature • Uses the noise immune Digital Communication Protocol (DCP), which utilizes interrupts for fast response to fires • Two built-in power/alarm LED’s • Programmable Non-polling LED’s • Non-directional smoke chamber • Vandal resistant security locking feature • Removable smoke labyrinth for cleaning or replacement • Compatible with the analog sensors
The ACA-V chamber consists of a light emitting diode (LED) and photodiode arrangement. The chamber is designed such that light emitted by the LED cannot normally reach the photodiode. In the event of fire, particles of smoke enter the chamber and scatter the light. As the smoke level increases, the scattering effect increases, causing more light to hit the photodiode. The chamber contains a unique design which allows smoke to enter the chamber while preventing external light from affecting the photodiode. The photodiode input level is sampled to sense smoke density. When the smoke density exceeds a preset threshold the sensor transmits an interrupt to the fire control panel indicating a fire condition. The fire alarm control panel can adjust the sensor threshold to compensate for contamination. The ACA-V Heat portion incorporates a highly linear thermistor circuit, with the thermistor mounted externally. The specially designed cover protects the thermistor while allowing maximum air flow. The thermistor circuit produces a voltage proportional to temperature which is scaled, and transmitted as a digitally encoded value to the control panel. When the ambient temperature exceeds a preprogrammed threshold (fixed temperature), the sensor transmits an interrupt to the control panel indicating a fire alarm. The fire alarm control panel can adjust the sensor threshold for different Standard’s requirements. Up to 127 devices are permitted on each loop. A sensor address can be set by a hand held programming unit. The sensor mounts to an electronics free base and incorporates a locking mechanism for secure installation. The base provides mounting slots, terminals for field wiring and a third contact for a remote indicator/LED. The sensor incorporates dual LED’s for easy viewing of sensor status.
SPECIFICATIONS: Operating Voltage 17-41 VDC Standby Current 450μA Alarm Current 540μA Transmission Method DCP – Digital Communication Protocol Operating Temperature 14°F (-10°C) – 122°F (50°C) UL Temperature Range 135°F (57°C) – 150°F (65°C) Storage Temperature -4°F (-20°C) – 140°F (60°C) Range Maximum Humidity 95% RH Non-Condensing Color & Case Material Ivory Weight 4.2 oz (5.9 oz. with 4″ base) Dimensions 3.9″W x 1.8″H Bases 4″ YBN-NSA-4 6″ HSB-NSA-6 6″ ASB S