Class E Circuits

[Alwayslearningelec]

In a Class "E" addressable system what devices(indicating/notification) require separate circuits. I know the with a speaker/strobe you have separate wiring for the speaker and strobe and then a/b alternating circuits. But as far as pull stations strobes etc. which can go on the same "loop" circuit? Just curious

 

[nhfire77]

In a Class "E" addressable system what devices(indicating/notification) require separate circuits. I know the with a speaker/strobe you have separate wiring for the speaker and strobe and then a/b alternating circuits. But as far as pull stations strobes etc. which can go on the same "loop" circuit? Just curious

what the hell is a class E circuit, never heard of it. Style E, yes, but in the 2010 nfpa 72 went back to just class A and B.

If, you are talking about mixing a NAC and and SLC in the same cable, yea thats OK, unless the manufacturer or AHJ says no.

 

[ron]

I'm guessing he is talking about a high rise base building fire alarm system in NYC.

The drawings required by the FDNY will dictate the circuiting.

 

[Alwayslearningelec]

I'm guessing he is talking about a high rise base building fire alarm system in NYC.

The drawings required by the FDNY will dictate the circuiting.

Looking at the riser it does not indicate wire sizes but as far as 4 pair #16, 4 pair #18 for devices I'm ok. It show different/separate circuits for the speaker/strobes,strobes, then separate for pull station then separate for warden stations. I was not sure if that represented how they actually wanted it wired? They don't shoe wire sizes which they usually do so that's why I'm questioning this.

 

[gadfly56]

Looking at the riser it does not indicate wire sizes but as far as 4 pair #16, 4 pair #18 for devices I'm ok. It show different/separate circuits for the speaker/strobes,strobes, then separate for pull station then separate for warden stations. I was not sure if that represented how they actually wanted it wired? They don't shoe wire sizes which they usually do so that's why I'm questioning this.

It sounds like someone stuck you with a generic riser diagram for the system. Typically they'll show smokes, heats, pulls, strobes, speaker/strobes and horn/strobes as if each type of device is home-run to the panel; all smokes on one line, all heats on another, etc. This is the height of laziness. The exception might be if someone is doing voice-evac with a conventional panel, but I don't think that is likely. Communication (voice or A/V), phones, and alarm devices (including monitoring and relay modules) will all have separate circuits. The important things will be whether anything is wired Class A and where CI cable is required, if at all.

 

[Alwayslearningelec]

It sounds like someone stuck you with a generic riser diagram for the system. Typically they'll show smokes, heats, pulls, strobes, speaker/strobes and horn/strobes as if each type of device is home-run to the panel; all smokes on one line, all heats on another, etc. This is the height of laziness. The exception might be if someone is doing voice-evac with a conventional panel, but I don't think that is likely. Communication (voice or A/V), phones, and alarm devices (including monitoring and relay modules) will all have separate circuits. The important things will be whether anything is wired Class A and where CI cable is required, if at all.

Thanks Gadfly. What do you mean by CI cable. Communication Interface???? They want us to run network cable to tie the DGP's etc

 

[gadfly56]

Thanks Gadfly. What do you mean by CI cable. Communication Interface???? They want us to run network cable to tie the DGP's etc

Circuit Integrity. Designed to survive 2 hours in a raging inferno, get smacked with a stream from a fire hose, and still carry current. Used in any situation where you are doing other that total evacuation at the first alarm; defend-in-place, floor above floor below floor of incidence, or areas of refuge, to name a few. It's mighty pricey, but you usually use it for risers only, or if you network the voice/notification components.