Shunt Trip Elevator Shutdown

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new_ee

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The building code in my area requires elevator power to be disconnected before the fire sprinkler system goes off if the elevator equipment room has sprinklers.

If anyone has experience with this how do you meet this requirement?

Enclosed circuit breaker with shunt trip?
Fusible disconnect with shunt trip?

Is either of these two options much better than the other? Is there a big price difference?

Do elevator controllers usually have a shunt trip built in or does it depend on the manufacturer?

Do elevator manufacturers provide their own controllers? Looking at major elevator manufacturers websites I was having a hard time finding anything about controllers.
 
This is one of the more difficult things to design correctly. I always use a circuit breaker with a shunt trip. (I've never heard of a fusible disconnect with a shunt trip. I'm not sure if there is any such animal).

Anyhow, you have to figure out were the source of your shunt trip voltage will come from. When the fire alarm panel detects heat, it should send the signal to trip the shunt trip. However, there should be a time delay before tripping the breaker so the elevator can get to the recall landing. So the fire alarm panel also has to recall the elevator. (Best would be feedback from the elevator control panel to tell the fire alarm panel the elevator is stopped at a landing, and then have the shunt trip. I've never got the elevator people to provide that from their control panel, though. And you don't want to make the trip circuit too complicated, or it might not work.)

Finally, there is a NFPA requirement (forget which code) that says the fire alarm panel has to monitor the shunt trip voltage, and send a trouble signal if the voltage disappears. You have to be careful where you monitor this voltage at. If you monitor it at the source, and a downstream connection is broken, then the monitoring won't help.

Steve
 
Most of the time, you will find that coordinating the elevator electrical is the designers responsibility. On the ones I've done, I have spec'd the shunt trip breaker. We specify heat detectors adjacent to the sprinkler head. These detectors operate at a lower temperature than the sprinkler and will shut down the elevator prior to the sprinkler going off.
The elevator people I've worked with are usually quite knowledgeable and have checklists to help with the design, but the responsibility belongs to the designer.

Jim T
 
steve66 said:
This is one of the more difficult things to design correctly. I always use a circuit breaker with a shunt trip. (I've never heard of a fusible disconnect with a shunt trip. I'm not sure if there is any such animal).

Anyhow, you have to figure out were the source of your shunt trip voltage will come from. When the fire alarm panel detects heat, it should send the signal to trip the shunt trip. However, there should be a time delay before tripping the breaker so the elevator can get to the recall landing. So the fire alarm panel also has to recall the elevator. (Best would be feedback from the elevator control panel to tell the fire alarm panel the elevator is stopped at a landing, and then have the shunt trip. I've never got the elevator people to provide that from their control panel, though. And you don't want to make the trip circuit too complicated, or it might not work.)

Finally, there is a NFPA requirement (forget which code) that says the fire alarm panel has to monitor the shunt trip voltage, and send a trouble signal if the voltage disappears. You have to be careful where you monitor this voltage at. If you monitor it at the source, and a downstream connection is broken, then the monitoring won't help.

Steve
Click to expand...

Here is a link to a fusible shunt trip disconnect:

http://www.ferrazshawmutsales.com/2005newpdfs/engineeredswitches.pdf
 
shunt trip

shunt trip

If my memory serves me well here in the "Peoples Republic of Mass." no longer requires a shunt trip, but it does require elevator recall to designated floor. I would check with the local building and fire code we're your working.
 
We just did a couple of these. The boss said each shunt trip breaker cost $750.
Al, the elevator man, said that they have a battery backup to move the elevator somewhere.
~Peter
 
lowryder88h said:
If my memory serves me well here in the "Peoples Republic of Mass." no longer requires a shunt trip, but it does require elevator recall to designated floor. I would check with the local building and fire code we're your working.
Click to expand...

Are AHJ's allowed to strike out: ASME A17.1-2004, Safety Code for Elevators and Escalators, Rule 2.8.2.3 requires that where sprinklers are installed in hoistways, machine rooms, or machinery spaces, a means must be provided to automatically disconnect the main line power supply to the affected elevator(s) upon or prior to the application of water.

I'm just curious.

TXInspect
 
iwire said:
I know we disconnected a few of these shunt trips in RI under the direction of the elevator inspectors.
Click to expand...

They gave you no reason as to why?

In Texas...elevators installed prior to 3-16-1985 do not require shunt tripping, but every elevator installed since that date does providing that the hoistway is sprinkled.

For those who have interest in the Texas requirements here is a one page link concerning shunt tripping from TDLR.

https://www.license.state.tx.us/elevator/b02_03_97_02.htm

TXInspect
 
We just finished an elevator. What we did was to provide a shunt trip 80 amp breaker enclosure. Then we went from a 120 volt leg to a relay, which the fire alarm contractor supplied in a 4 square next to the shunt trip. The relay is a normally open contact inline with the shunt trip power. Really a simple procedure.
 
OTIS Standard Note#19. IF SPRINKLERS ARE INSTALLED IN THE HOISTWAY, MACHINE ROOM, OR MACHINERY SPACES, THE LOCAL CODE MAY REQUIRE A MEANS TO AUTOMATICALLY DISCONNECT THE MAIN LINE POWER SUPPLY OF THE AFFECTED ELEVATOR PRIOR TO THE APPLICATION OF WATER (CONFIRM WITH LOCAL CODE OFFICIAL). SMOKE DETECTORS SHALL NOT BE USED TO ACTIVATE SPRINKLERS IN HOISTWAYS, MACHINE ROOMS OR MACHINERY SPACES OR TO DISCONNECT THE MAIN LINE POWER SUPPLY.

In other words, if your local code says it has to be done, you are responsible for making it happen.
 
i have done a bunch of these and we use heat detectors for the shunt trip. They are not life safety devices but are pretty sensitive to the rise of heat and give adequate monitoring of the heat inside the shaft(top and bottom), elevator equipment room, or wherever else they are required. We were to place them within one foot of the sprinkler head in each shaft. If the shaft wasn't sprinkled, they were not required. Local code thing.
 
(I've never heard of a fusible disconnect with a shunt trip. I'm not sure if there is any such animal).
Click to expand...
And another fusible shunt trip specifically for elevators.
http://www.bussmann.com/library/bifs/1145.PDF
Rarely can you take the shunt trip signal from the fire alarm directly to the shunt trip device. I may burn out the shunt strip, due to lack of amperage delivered from the fire alarm equipment.
Just my $.02
 
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