Elevator Bypass/Shunt trip

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There was a discussion about having a 'bypass' for the elevators that are fed off a shunt trip breaker.

So far I have not found a NEC 2008 code violation. The reason they want to install the shunt trip breaker in a bypass equipment is if the shunt trip goes bad(coil etc.) or malfunction then in an emergency situation they can 'bypass' this breaker and feed the elevators so they use them while the breaker is getting ordered or replaced. Of course when they actually do the work of replacing the breaker it will have the power off to the elevators.

So are there any code issues that are a concern here??

Just in case your wondering there is a another 'main' breaker that feeds this shunt trip breaker that is about 7 floors up, so the conductors will be protected regardless.
 
What code rule allows an elevator to remain in service without all of its required safety features operational?

I do not know of one, thats why I ask the question is there a code violation to have this type of set up.
The bypass can be wired 'supervised' to where if its in bypass it gives an alarm/light to the 24hr staffed area.

Its not that they expect a 'high' failure rate of the shuntrip breaker, its just that in this particular situation (hospital) if they lose the elevators technically they are not suppose to even be open.

In the rare case they have to move a patient while those elevators are down and there is a rush, this can be critical.
After talking with some with the others about a potential plan/idea they have concerning this setup, apparently the bypass will only be manually operated in the elevator control room by one of their 24hr staff who will have to remain there to take it out of bypass immediately when the patient is secure and only if a nurse/doc etc says they need the elevators to move asap (basically a 1 in 100,000 case where the loss of power was due to that shunt trip breaker malfunction).

I have heard of these breakers failing/going bad, either because of the coil or just the breaker itself. Maybe its just a certain brands that fail more often than others because other guys claim these breakers dont fail too often.

Some of the 'old timers' claimed they had this happen before at the Hospital when the breaker failed and the elevators were not running and the spare breaker was not available as fast as they want it nor in stock. The Director of the facility was not happy nor was the doctors, nurses etc.. !

I also know that even when the 'fire alarm' is going off and the elevators are being recalled, the nurses/doctors have an 'overide' key for 1 of the elevators that they can use to operate that 1 elevator even when the fire alarm is going off if a patient is in dire need of it.
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nhfire77

Senior Member
Location
NH
What code rule allows an elevator to remain in service without all of its required safety features operational?

I second that.

Its meant to kill the power so no one uses it, so you want bypass it, so someone can use it?

That is a very dumb (not you just the fact they want that) and dangerous idea. It will not get fixed fast enough, it will be bypassed and then there will be a fire. See Murphy's Law.
 

nhfire77

Senior Member
Location
NH
I also know that even when the 'fire alarm' is going off and the elevators are being recalled, the nurses/doctors have an 'overide' key for 1 of the elevators that they can use to operate that 1 elevator even when the fire alarm is going off if a patient is in dire need of it.
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Is that permissible in ANSI 17.1? Or is there something I don't get. That seems also very dangerous. Unless the person with the key is properly trained.


I have worked in hospitals, in the electrical capacity and the medical capacity, never seen that, but hey its Friday, anythings possible
 

jusme123

Senior Member
Location
NY
Occupation
JW
Is that permissible in ANSI 17.1? Or is there something I don't get. That seems also very dangerous. Unless the person with the key is properly trained.


I have worked in hospitals, in the electrical capacity and the medical capacity, never seen that, but hey its Friday, anythings possible

....so when the Doctors yelled, 'paddles,' they looked for you? :)
 

jap

Senior Member
Occupation
Electrician
The reason they want to install the shunt trip breaker in a bypass equipment is if the shunt trip goes bad(coil etc.) or malfunction then in an emergency situation they can 'bypass' this breaker and feed the elevators so they use them while the breaker is getting ordered or replaced.

If the Shunt Trip coil goes bad,,,, then it won't trip and it will remain energized anyway.
 
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