Manual pull station

FIGURE M.2 Fire alarm manual pull station. 

Manual pull stations are provided as part of the notification system, and all requirements are found in NFPA 72. These are manually activated initiating devices that will sound the audible and visible notification when pulled. The technology behind pull stations is simple They usually incorporate either a two position switch or momentary switch wired in an open circuit. When the activation handle is pulled or slid, this in turn throws the position of the switch, which closes the circuit and signals the alarm panel to activate the systems notification devices. 

Manual pull stations. NFPA Article 72A 5-8.1.2 requires the distribution of manual fire alarm pull stations throughout the protected area. 

In new H-6 facilities, transporting HPMs in code-required exit corridors is prohibited. In existing facilities, the UBC and UFC will allow transportation of HPMs in the exit corridors only if spill-alarm signaling devices are provided at 150-foot intervals (among other requirements outlined in other sections). The purpose of the HPM emergency spill alarm is to initiate a local alarm and to report to the ECS the conditions of the spill, leak or other accident within the exit corridor used to transport HPMs. Although a manual pull station is acceptable by the code, we recommend utilizing a fireman s telephone mounted in an enclosure. 

Manual Pull Station (MPS)/Manual Activation Callpoint (MAC)... 

A wide variety of sensing and initiating devices are available that can detect heat, smoke, radiant energy, and fire gas products. These devices should be selected based upon the type of fire anticipated. Additionally, sprinkler system water flow, activation of other extinguishing systems, and manual fire alarm pull stations can also be used to initiate an alarm signal. 

In a manual fire alarm system, the device used to activate the alarm in most cases is a pull box or pull station. The mechanism is very simple—puUing the switch either makes or breaks an electrical circuit which in turn causes an alarm to sound. As wiU be discussed more fiiUy in the next section, the alarm may sound only in the individual building, or the alarm could initiate a signal at a remote location as well. 

Infra-red light curtains at the stripper loading station and stacking conveyor discharge points shut down the operation of the machine triggered by an operator. Pull-switches and emergency stop pushbuttons located at strategic points perform the same task manually. 

The CLEM operator controls all machine operations from the control console in the cab mounted on the transporter trolley. The control of CLEM is semiautomatic that is, operations are performed automatically after the operator initiates a command. Interlocks to control the machine s operations have been incorporated into the design to meet safety requirements. Manual overrides are also provided to permit the operator to take control if necessary. The grapple speed and push-pull load requirements in handling fuel are controlled through all modes of operation. Indexing of the CLEM to a refueling station is accomplished by manually operated controls. 

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