FA RISER

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Alwayslearningelec

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Just curious how is the duct detector wired to a FSD? A FSD usually get 120v but what size FA wire is usually used?
 

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horsegoer said:
Just curious how is the duct detector wired to a FSD? A FSD usually get 120v but what size FA wire is usually used?
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Power to the FSD is routed through the on-board form "C" relay, which is typically rated to 10 amps or so at 120VAC. The connection depends on whether or not you are using the NO or NC side of the relay. The power to the damper is likely non-power limited, use Article 300 wiring methods suitable for the environment. This means likely no "fire alarm" wire (FPL, FPLR, or FPLP).
 
gadfly56 said:
Power to the FSD is routed through the on-board form "C" relay, which is typically rated to 10 amps or so at 120VAC. The connection depends on whether or not you are using the NO or NC side of the relay. The power to the damper is likely non-power limited, use Article 300 wiring methods suitable for the environment. This means likely no "fire alarm" wire (FPL, FPLR, or FPLP).
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Just to let you know I am not taking this off it was an old drawing and I am trying to learn from it. But the ducts and fsd are on the same loops as the pulls stations etc. so aren't they connect with initiating circuit(fire alarm wiring)
 
horsegoer said:
Just to let you know I am not taking this off it was an old drawing and I am trying to learn from it. But the ducts and fsd are on the same loops as the pulls stations etc. so aren't they connect with initiating circuit(fire alarm wiring)
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Ah, I see what you're talking about. I don't know of any major fire alarm manufacturer who makes an addressable fire/smoke damper, and that seems to be the only thing that would make any sense in this case. As far as I know, FSD's aren't alarm devices and so have no business on an indicating device circuit (IDC, conventional) or signal line circuit (SLC, addressable). While we're at it, someday I'm going to brain an architect or three with a copy of NFPA 170 to try and convince them to use the standard device symbols instead of their in-house junk.

Taking the drawing at face value, I can't tell what's going on here. Especially since there is a break in the group of FSD's located inside the cloud. Without seeing the full sheet and the notes, I'm leaning towards "crappy riser diagram" :thumbsdown: as the answer to your question.
 
gadfly56 said:
Ah, I see what you're talking about. I don't know of any major fire alarm manufacturer who makes an addressable fire/smoke damper, and that seems to be the only thing that would make any sense in this case. As far as I know, FSD's aren't alarm devices and so have no business on an indicating device circuit (IDC, conventional) or signal line circuit (SLC, addressable). While we're at it, someday I'm going to brain an architect or three with a copy of NFPA 170 to try and convince them to use the standard device symbols instead of their in-house junk.

Taking the drawing at face value, I can't tell what's going on here. Especially since there is a break in the group of FSD's located inside the cloud. Without seeing the full sheet and the notes, I'm leaning towards "crappy riser diagram" :thumbsdown: as the answer to your question.
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Sorry Gadfly I am just trying to understand. So the way the fsd and duct are shown are incorrect? They are not part of an adressable loop? They get 120v only?
 
IDC SFD Information

IDC SFD Information

The Smoke Fire Damper needs to be controlled by an addressable relay and a PAM-SD (from Space Age). The 120v for the Damper passes through one side of the PAM-SD which you will set to normally open. 24v needs to be run separately from the IDC and one leg landed on the addressable relay to normally closed to power the PAM-SD. The panel will be programmed to switch the addressable relay which in turn allows the 24v power to open the relay on the PAM-SD and kills the 120v going to the SFD.

This is the Fail-Safe method in case you lose 24v the sfd will close. If the AHU is pushing a lot of air you may want to wire the relays opposite to prevent damage to the duct work in case of 24v power loss.

Also most addressable relays allow the use of 120v directly on their relays, but it is preferable to add an extra degree of separation from FACP. I have seen a 24 floor high-rise lose every panel due to improper wiring of the addressable relay and having 120v sent back through the IDC and split out through the RUI Curcuit, 12 panels fried..
 
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DUCT Detector.

DUCT Detector.

Sorry, just noticed it shows and was stated about the duct detector. Same situation applies as above, except the Duct detector IS the addressable relay, and you use the relay output on the duct detector to switch the PAM-SD.

This information only applies to addressable systems.
 
hysticali said:
Sorry, just noticed it shows and was stated about the duct detector. Same situation applies as above, except the Duct detector IS the addressable relay, and you use the relay output on the duct detector to switch the PAM-SD.

This information only applies to addressable systems.
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Thanks A LOT!!! Very helpful.
 
hysticali said:
Sorry, just noticed it shows and was stated about the duct detector. Same situation applies as above, except the Duct detector IS the addressable relay, and you use the relay output on the duct detector to switch the PAM-SD.

This information only applies to addressable systems.
Click to expand...

This is possibly what's happening, but you "assume facts not in evidence". Note that the FSD's are shown connected on the alarm loop, while the duct detectors are t-tapped off the individual FSD's. This makes no sense. And what about the break in the loop??
 
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gadfly56 said:
This is possibly what's happening, but you "assume facts not in evidence". Note that the FSD's are shown connected on the alarm loop, while the duct detectors are t-tapped off the individual FSD's. This makes no sense. And what about the break in the loop??
Click to expand...

I was only answering the general question about the hook-up to the FSD. Anything more and you would need to be able to see more of the drawings to read the matrix and any notes applied to the shutdown. If this is a high-rise things get more complicated, and depending on what state your in would also change how you would control the shutdown in the programming of the FACP.
 
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