shunt trip breaker

[cousinwillie]

what is this for and where does it go

 

[charlie b]

This thread had been temporarily closed. This action was taken because the nature of the question and the occupation shown in the Original Poster's profile raised a concern that this may have been an attempt by a Do It Yourself person to obtain "how-to" information.

In an exchange of Private Messages, the Original Poster has provided assurances that he was a licensed electrician for many years, and is now only doing the occasional small jobs. Therefore, the thread is being reopened. I offer an apology to the OP for the inconvenience and the delay.

 

[charlie b]

I am not sure I understand exactly what you are asking for. A shunt trip breaker is an overcurrent protection device, just like any other breaker, except that it can be tripped from a remote location. It will have an electromagnetic coil (or other device, I am not current on the more modern technologies here) that, when energized, causes the breaker to trip open. Generally, it will not have a similar device to allow it to be closed by a remote action. The types of things that are used to remotely trip a breaker include load-shedding schemes (i.e., you trip some loads to make sure the generator is not overloaded when it comes on line), protective schemes (e.g., to trip off an air compressor when the system detects a break in an air pipe), and remote manual switches (i.e., to allow an operator to control equipment from a central control station).

 

[celtic]

what is this for and where does it go

To trip the CB.
In a panel.


Maybe a bit more info will yield a better response?

 

[cousinwillie]

ok ,this guy is putting in a sub-panel coming off a three phase panel,he may not even need a shunt,I just needed to know for sure what it was for,but according to the same guy,all this sub-panel is going to be used for lighting and receptacles,because it's going to be a bar and the sub-panel is going to be upstairs where the bar itself is located and the main panel down stairs why would you need a shunt breaker?

 

[zog]

what is this for and where does it go

There really is not such thing as a "shunt trip breaker", a shunt trip is an accessory in a breaker, the inouts vary widely depending on what type of breaker you are asking about, for small MCCB's charlie nailed it, for power breakers there are many more variations.

 

[quogueelectric]

what is this for and where does it go

It is a circuit breaker with two wires attatched to it so that when the two wires have the proper voltage applied to them it causes the breaker to trip immediately shutting the breaker off.

A simple example would be an electric fryer in a restaurant.

Usually this would have an ansul system protecting it however when the ansul system discharges it trips one or more micro switches which in turn energizes the shunt breaker causing it to trip and shutting down effectively the source of the fire once the grease fire has been put out.

It is not uncomon for an entire kitchen panel to be on a shunt trip main. And in the fire protection scheme usually a gas solenoid valve may be powered off this breaker so that an ansul trip will trip the breaker suppling the main gas solenoid to the cooking area .

 

[cousinwillie]

that is exactly what I thought because I had to do one at a campground in Va.for their restaurant above the cooking area

 

[charlie b]

. . . this sub-panel is going to be . . . upstairs where the bar itself is located and the main panel down stairs. Why would you need a shunt breaker?

This situation does not require a shunt trip breaker. In the sub-panel, you don't even need a main breaker (i.e., it could be main lug only). The breaker in the main panel can protect the feeder and the sub-panel, and is sufficient to isolate the sub-panel for maintenance.

 

[Billy_Bob]

I have seen these used for fire related systems. Like a fire sprinker system - sprinklers spray water -> main power shuts off.

 

[electricalperson]

you can also use a shunt trip to shut power off to a subpanel with an emergency stop button. you can use it for anything you want basically.

the shunt trip device usually attaches to breakers that are able to take accessories. you can also buy breakers with shunt trip built in. they have a couple wires hanging off of it and you bring power to that

one company wanted us to install shunt trip breakers for there data equipment. the building had a small data center inside and if they lost the air conditioner in the room the room might get too hot and trip the sprinkler system. the stuff they had was not that crucial and could be turned off but they didnt want to spend 100,000 dollars on new equipment if the air conditioner fails

they were controlled by a 24 volt thermostat that went to a relay that switched the 120volt power to the units. when it hit 90 degrees in the room, bang they would trip. the ac kept the room at around 75 even at full power

 

[480sparky]

For those who haven't seen a shunt trip:

 

[LarryFine]

One more thing: Most shunt-trip breakers are not designed to have the tripping coil constantly energized, especially when the tripping voltage is higher, such as 480v. Some open the power to the tripping coil when they trip, and some don't.

If the breaker powers the circuit that trips it, then it doesn't matter. However, if it doesn't open the coil circuit, and it's not supplying itself, then the tripping voltage must be temporary, or auxillary contacts must be included in the breaker.

 

[ce2two]

They are also used in computer rooms ,hit the mushroom red button it then energizes the coil with in the breaker....Also found in traffic signal cabinets through out california like 80% ,if one of the 15 amp shunt trip breakers trip the signal goes on flash??????????????????

 

[tesla fan]

They are also used in conjunction with fire alarm systems to shut off elevator motor, heat detector in elevator mech room is wired to shunt trip

 

[electricalperson]

They are also used in conjunction with fire alarm systems to shut off elevator motor, heat detector in elevator mech room is wired to shunt trip

i was at a local club in providence RI (the living room) and the fire alarm went off which in turn activated a shunt trip and turned off all power to the stage. i think that was a new fire code that everyone had to do following the station night club fire. they all needed to install sprinklers too

 

[peter d]

i was at a local club in providence RI (the living room)

The Living Room? Did you disinfect your clothes after you went in there?

The RI Fire Alarm Code requires music/dj equipment shutdown upon initiating device activation. It also requires the house lights to come on as well. It makes for some interesting logic trying to figure out what circuits to deactivate and what circuits to turn on.

 

[LarryFine]

i was at a local club in providence RI (the living room) and the fire alarm went off which in turn activated a shunt trip and turned off all power to the stage. i think that was a new fire code that everyone had to do following the station night club fire.

It's really just an easy way to get the building evacuated. Nobody wants to stay when the music dies.

 

[LarryFine]

The RI Fire Alarm Code requires music/dj equipment shutdown upon initiating device activation. It also requires the house lights to come on as well. It makes for some interesting logic trying to figure out what circuits to deactivate and what circuits to turn on.

Shouldn't be any tougher than wiring a typical commercial kitchen system.

 

[iwire]

Shouldn't be any tougher than wiring a typical commercial kitchen system.

Neither is tough, both are very simple. :smile: