Re: fire door
UL 864 is a 119 page document which gives the manufacturer all the information to design, build and test the device. In this document, a "end-of-line device" is defined as a device installed at the end of a circuit for the purpose of monitoring the circuit for fault conditions.
I wonder if the engineer has specified the right UL standard.
The book goes on to say:
"1.5 These requirements do not cover the following:
........
c) Equipment intended for use in fire protective signaling systems used to detect, monitor, signal, or control a fire condition;"
Isn't an indicating switch on the fire door meant to signal the position of the door in case of fire? And shouldn't this switch be rated for fire duty?