In an automatic system, the closing of any one of the normally open heat detection devices will cause the Control Unit or Circuit Monitor Panel to discharge the electric actuator. The pressure generated from the discharge of the electric actuator forces the piston through the seal of the actuating nitrogen gas cartridge, the gas then moves through the actuation lines to the slave actuator where a piston punctures the seal of the pressurising cartridge. The released gas flows to the agent tank and distributes the fire suppression agent into the protected areas of the machine.
If the automatic detection feature of the system has been disabled, or was not installed, the system will not discharge unless manually actuated. Manual actuation is accomplished by pulling a safety pin and striking down forcefully on the push knob on a mechanical actuator assembly. This action also forces the piercing rod through the seal of the compressed nitrogen gas cartridge.
The AFEX fire suppression system is a pre-engineered dry chemical, liquid agent, or dual agent system. It is designed to suppress fires that occur on heavy duty mobile equipment. Typical applications are found on machines used in surface mining, logging, landfill, agriculture, resource recovery, oil and gas, slag operations, buses and transportation applications, and special uses such as conveyor belts, compressors and generators.
The fire system described is a suppression system only and is not designed or intended to suppress all fires.