Shunt trip breakers

[elvis_931]

Can anyone give me a crash course in shunt trip wiring of vent hood for a restaraunt, and the theory behind it; the need for it? Please?
Thanks in advance.

 

[Buck Parrish]

If you have outlets in or behind the commercial range hood.
The hood has fire protection equipment. When you pull the leaver to activate the spray to extinguish the fire. The oulets should loose power at the same time.
Most of the newer hoods come equipped with relays that make the install very easy,

 

[LarryFine]

Here's the basics:

Upon automatic or manual tripping, the exhaust fan must come on or stay on.

Everything else, such as the intake fan, any electrical appliances and/or receptacles, gas (may or may not be electrically controlled), lights (usually), etc., under the hood must lose power.

Often, a horn/strobe must activate.

In some applications, a building fire alarm must go into alarm.

In some localities, the gas must cut off every time the exhaust is shut off, and a solenoid valve reset box must be reset and then the pilots relit after turning the exhaust back on. (The cooks hate this one.)


The reasoning? To minimize smoke and make the fire easier to extinguish.

Shunt-trip breakers are only one way of accomplishing this. I often find relays easier and cheaper to use.

 

[quogueelectric]

Lately the most recent jobs I have done including these setups, shut down the main for the entire kitchen panels thereby shutting down all cooking equipment in the kitchen which could be causing the fire. For example if an electric deepfryer caught fire and tripped the ansul system it would trip the kitchen panel which was feeding the power to the fryolator to help extinguish the source of heat while the ansul was working to put out the grease fire. There are numerous other fire code related functions which you should not be getting involved in unless you are qualified or instructed by a licensed fire system installer/designer such as Simplex/Pyrotronics and there are others.

 

[electricalperson]

Lately the most recent jobs I have done including these setups, shut down the main for the entire kitchen panels thereby shutting down all cooking equipment in the kitchen which could be causing the fire. For example if an electric deepfryer caught fire and tripped the ansul system it would trip the kitchen panel which was feeding the power to the fryolator to help extinguish the source of heat while the ansul was working to put out the grease fire. There are numerous other fire code related functions which you should not be getting involved in unless you are qualified or instructed by a licensed fire system installer/designer such as Simplex/Pyrotronics and there are others.

shutting down the entire kitchen seems like a good idea and isnt much harder than shutting down the gas valve and outlets under the hood. simplex is pretty good at explaining things to you. the guys i worked with were pretty smart about the system and didnt mind to take the time to explain it

 

[quogueelectric]

shutting down the entire kitchen seems like a good idea and isnt much harder than shutting down the gas valve and outlets under the hood. simplex is pretty good at explaining things to you. the guys i worked with were pretty smart about the system and didnt mind to take the time to explain it

When you do the job right it gets very expensive very quickly and there are heartless contractors out there who dont understand the legal process and why it is in force is because other people lost thier lives in a fire because of this. Safety is important and just like you put your life in the pilots hands when you board a plane you would like to know the electrician is competant to be doing your work.

 

[LarryFine]

Lately the most recent jobs I have done including these setups, shut down the main for the entire kitchen panels thereby shutting down all cooking equipment in the kitchen which could be causing the fire.

That's a good idea, and I've re-used existing shunt-trip mains. The one problem with that is that the exhaust fan(s) and horn-strobe must receive power after a trip, meaning they require another source of power.

I have tapped the incoming feeder with Kup-L-Taps to set a small sub-panel for the above-mentioned items, plus anything else they'd rather not lose power on during a trip (as long as it's not required to be de-energized.)