A: Each NAC (Notification Appliance Circuit) in a fire alarm panel or booster power supply has a maximum current rating. This information can be found in the manuals provided with the panels. The total current draw for all the devices connected to the circuit cannot exceed the NAC rating.May 2, 2014
What is a NAC module?
Advanced Intelligent NAC Module is an addressable module for use with the AxisAX Series Intelligent Fire Alarm Control Panel's SLC Loops. ... Each module also supervises the wiring for opens, shorts and grounds and reports this status back to the intelligent fire alarm control panel.
How does a signaling line circuit work?
The Signaling Line Circuit (SLC) carries signals both to and from the panel; it uses data to carry the signals out from the panel to field devices, and data to carry the signals back from the field devices to the panel. The SLC also provides a small amount of power to operate the field devices.
How does a fire alarm NAC work?
During alarm conditions, when the voltage on the Notification Appliance Circuit (NAC) is as shown, the diode conducts to allow power to light or sounder. During non-alarm conditions, the voltage of the NAC opposite so the diode will not conduct.
What is NAC output?
Product Description. The PROACTIV® Output Control Module – NAC (OCM–NAC) provides 4 or 8 Notification Appliance Circuits, which supervise and control notification appliances across the protected space. The OCM–NAC is supplied as a surface or recess-mounted wall unit in a standard 4 gang electrical back box.
What is a NAC expander?
LifeSafety Power's four-zone Notification Appliance Circuit (NAC) Expander Power Supplies are designed to extend the power capabilities of existing NACs and provide power for auxiliary devices. The units can connect to any 12 or 24V Fire Alarm Control Panel (FACP) or operate as a standalone system.
The short on the wires is caused by installing the bell backward. ... I've seen quite a few instances where fire alarm installers put the horns or strobes in backward because they put the positive wire to the positive terminal and the negative wire to the negative terminal.