EST QS4 class A + class B initiating circuit w/Ground Fault

[devonb]

We have a new customer that has a QS4 with a ground fault. We have isolated it to the circuit with all the smokes and pulls for the entire building. The circuit is Class A out to the modules, then from the modules it is Class B, conventional AND addressable devices mixed. (I think this is correct, alarms will show address of area but not specific device address eg, "Lobby Smoke Detectors" when there are four detectors.)

Our problem is we have no idea how the system wiring goes from one module to another, no idea where half-way point is, no idea what is the first module, second module, etc on the circuit. It could take two or three days of labour for 2 or 3 techs to figure this out. Also we have never installed an addressable system yet and are unfamiliar with the way modules are wired (schematics).

I was hoping someone had suggestions to make this easier, such as where to find schematics for the modules, or if module LEDs indicate anything useful, or what terminals to put an ohmmeter on on modules.

Let me know if you need more info such as specific module model numbers etc. Any help is appreciated!

[Firetech1701A]

Start by opening the Class A circuit at the Panel then go out to the Field go a little ways from the panel find a smoke Detector or Monitor module Pull Station water flow switch or tamper switch disconnect the SLC/DATA side. After you open the circuit your going to have devices go missing. Check to see if your ground fault stays or goes away if it goes away look at what is missing. If it don't go away go down a little bit father and open up the SLC/DATA circuit again. Go back to the 1st Device you opened up and put it back together and see whats missing and check your ground fault. I'm some what new to Quick Start system there might be any easier way. Also keep in mind that even addressable devices can give you ground fault if it got wet. That's how I would start with a system I have never worked on before. Don't let the fact that its a addressable system get the best of you its not much different from a conventional system.

[FireTech]

What exactly does the Trbl say on the Panel? IE- Grd Flt- 01-01-0676 (pp-cc-dddd) What zone #? (I think you can hit either details or enter button when viewing the trbl to obtain actual zone #?

Do you know what type of module the Conventional smks are wired to? Ie- 2-Smk and Siga-UM OR with a Siga-CT1? I wonder if there are wires coming off of the PS-6 system power supply that feed the 2-smk/Siga-um module for smoke power?

Look at same examples I have attached for you that show how conventional smks might be set up....