Fire alarm light switch

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Fire alarm light switch

A few days ago a friend and me had the idea to make a fire alarm pull station the lightswitch in my room. Anyone know if that will work? If it will I need to know where i can get a pull station and how to wire it. Thanks for any info.

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Check the ratings first

Step one is to check the voltage and amperage rating of the switch --- can it handle the juice required to run a lamp. It would be ironic if a fire alarm pull started a fire.

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somthin like this...

I was thinking of somthing along the lines of this:

http://www.wheelockinc.com/products/sync_modules/manual_pull%20_stations.htm

it seems simple enough. The only problem is i cant find any specs on the switch.

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The problem you'll face is th

The problem you'll face is that even if the switch is capable of handling the voltage/amps, those boxes are designed to be turned off with a key. The spec sheet says that to reset (turn off) the switch, you need to open the box with a key and reset the handle upright. Pretty inconvenient for when you wanna turn the lights off.

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if its just a normal toggle s

if its just a normal toggle switch im sure you could rig somthin up to have it bring the switch back to the normal position...i think the actual pull handle is plastic so im sure you could could just glue/screw somthin on there to have it go back up when the handle is pushed up. But i cant start moddin' somthin i dont have so the first step is to find one, but i have no idea how to go about doing that. Ive tried ebay but i can only find new ones sold in lots of like 4 or more. plus my mom wont buy anything over the internet wiht her credit card so that kinda rules ebay out anyways. i highly doubt it but if anyones got one lying around they dont need id be more then happy to buy it off you. thanks a lot.

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30 VDC @ 1 A is too small

The spec sheet for that model (its on that page your provided) is only 30 VDC @ 1 A. That is wholly inadequate for any kind of room lighting. It won't surprise me if all the fire alarm switches are like that -- I'd bet that fire alarm systems run at low voltages and currents.

You can still make it work, but now you need a circuit that can be triggered by the lower power from the fire alarm switch. An solenoid relay would probably do the trick. The fire alarm switch would control current flowing into a solenoid coil from a small DC power supply. The relay would then switch household current to power the room lights.

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i noticed that there is a sps

i noticed that there is a spst and a dpst model....whats the difference?

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He might just get away with a

He might just get away with a 25W incandencent bulb, or more likely a 5-15W energy saver...

Even so, the flurocent lamps can draw large currents on start up as the induction coil engergizes...so probally not very safe!!

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DPST = Double-pole/single-thr

DPST = Double-pole/single-throw , i.e, both live and negative are disconnected / connected when in use.

SPST = Single-pole/single throw - Only one line connected / disconnected when switch is used. This is normally the live line btw...

For a 12V relay circuit either will be fine. I would personally go for the SPST switch.

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good

good, the spst model is cheaper. it needs to be able to power a ceilingfan/light thingy with 3 bulbs. i like the relay idea but i dont know how my dad would feel about putting somthin i wired into my wall....

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ebay

i got my parents to let me bid on ebay and found a lot of 5 pull stations. I am the current high bidder and the auction ends in a day. I know this a stupid question but what do i do if i win?will the contact me or somthing?

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amps

i finnaly got an alarm box and the switch is rated at 125volts ac 3 amps. is this enough to handle 3 25w bulbs?

thanks so mch for your guyses help!

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Interestingly, in theorie tha

Interestingly, in theorie that should be able to support 25W bulbs...I STRONGLY recommend you don't do it, as those fire pulls are not designed with that in mind.

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done!

i tried it and it works perfectly. thanks so much for your guyses help, i appreciate it.

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Cool, post pics. BTW, 3A at

Cool, post pics. BTW, 3A at 120V is 360W

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pics

theres a pic of it in my image gallery. ill post a few more once my camera/imovie stops acting up

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According to...

According to the spec sheet, these pullboxes are rated for 1 amp @ 30 volts DC

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Fire alarm pull station light switch

Does anybody know if a fire alarm pull station will run one 60 watt bulb?

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No.

According to a previous post, the pull is rated for 1A*30V=30W. It's also built for direct current (DC).

The bulb takes alternating current (AC), and pulls 0.5A*120V=60W. The switch is underrated for the bulb's power draw. It would likely overheat and possibly start a fire.

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it depends.

If it is indeed 30VDC and 1A rated, then cwsmith is absolutely right, of course. At 30W max rating, a 60W AC load probably isn't going to fly. If it ends up being like the one the guy further up got, 125VAC 3A, then you're good to go. If you have the pull station in hand, check your switch ratings. If you've seen it on eBay, ask the seller.

I would mention that sometimes a switch is rated like 3A 125VAC AND also 30VDC 1A. If that is the case, then you might be in the clear. Again, check your switch specs.

You could also just change the switch out, depending on how it is designed. If it is just a microswitch actuated by the pull handle mechanism, then you could easily sub out something beefier.

mike

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find a way to incorporate an

find a way to incorporate an AC relay in there.

relays would probably handle more load than a switch

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Switches and power transmissi

Switches and power transmission hardware is always rated in current, never power. So, if the switch says 1A, then it'll carry 1A at 1V up to 1A at the highest rated power. The real issue is the voltage rating. It's probably rated at 30VDC because that's what every fire alarm system runs on. The two problems with voltage rating it dielectric strength and interruption capability. The first means what voltage the insulation can withstand with acceptable leakage, and the latter means what voltages won't jump across the contacts when you open it.

So, even though it's rated at 30V, you're probably fine at 110V because that's still a pretty low voltage if you stay under 120W bulbs there's probably no problems with capacity. However, since you're switch is only rated at 30vdc (and dc is much less likely to jump up when an inductor discharges) you may find that once you turn on the switch, you can't turn it off. It might just arc and burn when you try to turn it off. If you want to do an experiment, hook it up to a power strip that you can quickly turn off if that happens.

As an alternative, you could make a lower voltage AC below 30V to flow through the switch that then triggers a 120VAC relay to turn your light on and off.

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Relay

Wiring up a relay sounds like the safer option. The max rating on a switch is there for a reason: safety. just my 2¢ tho.

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This relay would work great:

This relay would work great for loads up to 360W:

G4B-112T1CUS-AC24

http://oeiwcsnts1.omron.com/pdfcatal.nsf/PDFLookupByUniqueID/09FF9B0AB74A4326862571480051527D/$File/G4B.pdf?OpenElement

$9.33 at digikey

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Deactivating sprinklers, alarms and firemen response

I just thought I'd start a thread to address preventing alarms and firemen showing up unexpectedly everytime you switch the lights. Also, better safe than sorry, making sure the sprinklers are on an isolated system, if not installed locally, then at least disconnected from the mains at the switch-housing's original location.

I'm no expert, so anyone that knows please correct me if I'm wrong, but before I even tested the mechanism, I'd make sure there weren't any obvious wires still connected to a remote alarm activation system that might alert local fire response teams. That'd be the first thing I did. Then I'd start to figure out how to wash off the fluorescent die that was all over my hands and shirt, and just remove that whole die spray thing altogether. Though likely amusing, there is little point in trying to figure out who it was who set off a false light switch.

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Say what? It's plastic and a

Say what? It's plastic and a little metal. Fire alarm switches aren't wireless transmitters with GPS receivers that summon the local fire department to their location with every pull.

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I'm reasonably sure

that C.M. is employing some tongue-in-cheek humor. I hope Wink

Though that dye thing is a good point if you're scavenging old pulls to use as light switches!

mike

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I can't tell anymore, and fra

I can't tell anymore, and frankly, I'm getting pretty tired of it.

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