Honeywell HPFF12CM 06/03 Each Siemens FDOOT441 unit is

Each Siemens FDOOT441 unit is UL 268 7th edition listed incorporating advanced built-in ISOtechnology™ - True Class-X SLC operation (use is optional) greatly improving system reliability and circuit integrity while providing advanced addressable fault finding

Together these sensors efficiently detect smoldering fires

After installation

and the initiating device loops share a common supervisory supply and ground

The MIX-M501MAP is a miniature monitor module that supervises a Style B (Class B) circuit of dry-contact input devices

Honeywell HPFF12CM 06/03 Each Siemens FDOOT441 unit isHPFF12 and HPFF12CM are twelve amp Notification Appliance Circuit (NAC) Expander Power Supplies designed to extend the power capabilities of existing NACs and provide power for auxiliary devices. The HPFF12 and HPFF12CM connects to any 12 or 24V Fire Alarm Control Panel (FACP) or operates stand alone.