Shunt Trip for fire alarm/elvator

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erock

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Have a 3 phase breaker with 4 breakers. I am assuming the 4th breake is the shunt trip. It has two wires and I am going to hook one wire to one of the leads returning from the 24v coil provided by f/a guys.
I am also running 120v power to coil(no neutral) . I am then going to hook other lead from shunt in panel to neutral. Is this the correct wiring
 
No.

The fire alarm contractor supplies a relay.

You have to confirm your shunt trip coil voltage.

If it is 120 volts, route 120 volts through the set of normally open contacts on the FA relay. Neutral goes to the other half of the shunt trip coil.
 
Tony S said:
Some clarification needed as to the type of elevator.

You could be entering a legal minefield.
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I agree.

Something has to recall the elevator, and there has to be a time delay before the shunt trip, correct?

If that doesn't happen there is a chance you are just trapping people in the elevator.
 
steve66 said:
I agree.

Something has to recall the elevator, and there has to be a time delay before the shunt trip, correct?
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This is the job of the smoke detector(s). Smoke is supposed to go off and recall prior to the heat. The heat should have a rating just below the rating of the fuse in the sprinkler head. If there is no sprinkler system then there is no need for a shunt trip device.
 
You must also supervise the control power to the shunt trip device and report loss of power as a supervisory signal. Most people forget , ignore or do not know this rule.

NFPA 72 2013 21.4.4
 
In many areas it is a common requirement for the elevator feeder to be controlled by a machine room heat detector.

This is in addition too smoke detector controlled elevator recall systems.

The elevator recall should have already brought the elevator to the primary or alternate floors before the machine room heat trips out the feeder.

However when the elevator is in recall mode the firemen can override it with their key and that could lead to trapped firemen.

In Rhode Island the state had us disconnect these shunt trips but in MA I think we are still installing them.

Bottom line is to make sure what the local code requires.
 
iwire said:
However when the elevator is in recall mode the firemen can override it with their key and that could lead to trapped firemen.
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They should know better. The elevator should only recall if there is smoke in the elevator lobby of any floor, the machine room or the hoist way. Overriding prior to investigation would be terribly un professional of a responding firefighter.
 
luckylerado said:
They should know better. The elevator should only recall if there is smoke in the elevator lobby of any floor, the machine room or the hoist way. Overriding prior to investigation would be terribly un professional of a responding firefighter.
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Or heroic, you can never tell till the dust settles.
 
Add to all of this, the elevator inspectors I have had the pleasure of meeting are notorious for making up pocket codes.
 
Once you get in to the field of elevators and fire codes the best advice I could give is “get a specialist consultant involved.” Lives and law suits don’t come cheap.

I don’t know how prominent Otis is in the US, in the UK they run emergency rescue courses for electricians.
All our electricians went on it after a bit of an unfortunate incident. The only person on site qualified in elevator rescue was stuck in the elevator. It took 5 hours to get me out of that damn box!
To add a perfect end to the day, I was taken to hospital with hypothermia.
 
Tony S said:
Once you get in to the field of elevators and fire codes the best advice I could give is “get a specialist consultant involved.” Lives and law suits don’t come cheap.

I don’t know how prominent Otis is in the US, in the UK they run emergency rescue courses for electricians.
All our electricians went on it after a bit of an unfortunate incident. The only person on site qualified in elevator rescue was stuck in the elevator. It took 5 hours to get me out of that damn box!
To add a perfect end to the day, I was taken to hospital with hypothermia.
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Funny you should mention Otis. I had a brief conversation with the mechanic for a job we supplied a panel for elevator recall only. He asked where the smoke in the hoistway was. I said there wasn't one. He said it needs one. I asked, did they suddenly put a sprinkler in the hoistway? and he said "No." I said, no sprinkler, no smoke detector. Sent him a copy of NFPA 72 (2007) 6.16.3.6. Waiting now to see what happens.
 
gadfly56 said:
...Sent him a copy of NFPA 72 (2007) 6.16.3.6.....
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I am not familiar with that reference but there is this from 2013.

"3-9.3.4 Smoke detectors shall not be installed in elevator
hoistways.
Exception No. 1: Where the top of the elevator hoistway is protected by
automatic sprinklers.
Exception No. 2: Where a smoke detector is installed to activate the elevator
hoistway smoke relief equipment."


I will offer this though as a former maintenance man in an 8 story building. The little crack in the floor between the elevator car and the floor at any given level is a fantastic place for people to throw mountains of cigarette butts. The elevator hoistway smoke detector and its ability to recall properly IMO is essential to a well designed life safety system regardless of sprinkler heads
 
luckylerado said:
I am not familiar with that reference but there is this from 2013.

"3-9.3.4 Smoke detectors shall not be installed in elevator
hoistways.
Exception No. 1: Where the top of the elevator hoistway is protected by
automatic sprinklers.
Exception No. 2: Where a smoke detector is installed to activate the elevator
hoistway smoke relief equipment."


I will offer this though as a former maintenance man in an 8 story building. The little crack in the floor between the elevator car and the floor at any given level is a fantastic place for people to throw mountains of cigarette butts. The elevator hoistway smoke detector and its ability to recall properly IMO is essential to a well designed life safety system regardless of sprinkler heads
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That is basically what is in the 2007 edition. Note the use of the word "shall". When it comes to codes, "shall" means "must", regardless of the quantity of butts in the pit. The AHJ has to specifically request the smoke detector if he wants one.
 
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