Class B Fire Alarm Wiring Diagram. What s the difference between conventional class a and b how does fire alarm wiring work free pdf diagram module e part 1 electrical exam prep canada wire contractor magazine circuit design control units ppt online is piping loop mike holt forum addressable alarms canadian consulting. Free pdf diagram class a wiring conventional and b module e part 1 electrical exam prep what is fire wire contractor magazine alarm work piping nac circuits alarms jules bartow communications circuit design basics 2 addressable canadian now n nfpa 72 2018 system.
The current as it leaves the panel goes out one of a pair of wires goes through a current limiting resistor called an end of line resistor eol and returns on the other wire. In other words the first end of the wire is. This pair along with the eol makes up a fire alarm loop.
System wiring explains the differences between slc class a and class b circuit wiring use of.
Types of fire alarm signals and differences between conventional addressable and analogaddressable fire alarm systems are also presented. Power is supplies from both directions one cut wire does not cause loss of function to a device on the circuit. Examine how an addressable fire alarm. In conventional fire alarm circuits if a wire breaks in a class b circuit some of the devices are disconnected from the panel if a wire breaks in a class a circuit the devices that would have been disconnected use an alternative wire path to the panel.