[iceman4160]

Okay its been a few years since I have done any firealarm system and now am currently installing a Simplex Mapnet II/ IDNET system with, my question is. When you have a Simplex Addressable Relay IAM for fan shutdown can the 24volt power from the IDNET cable that goes to the addressable relay IAM be used for your common on the C contacts of the relay portion of the IAM (which from the relay portion will go to a MR 201 relay to break the control circuit for fan shutdown). We had the Simplex rep out on the job the other day and I took it one way and my toolie took it another way . I say we need a separate power source ie: 24v supply from the Simplex FACP he understand that we can use the 24v from the IDNET cable used for the relay IAM and the rest of the system.

 

[NacBooster29]

The relay they provide has dry contacts only. In other words switching a seperate power source.

A typical rtu shutdown is done by breaking the low voltage side of the control transformer inside the rtu.

Newer fancy rtu's can have a set of contacts inside the wiring compartment, often times there is a jumper completing the circuit you must remove, and install your 2 wires from your fire alarm relay in nc, and c.
I can't remember ever pulling a seperare 24v from the facp to do any switching with.

 

[greenman]

It need,s an aux power supply.
You can not use the supply from the fire panel.
That is a rule for almost all fire panels.
Aux devices need Aux power supplies.
And watch your contact ratings.