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Shunt trip wiring QO240-1021

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nizak

Senior Member
Excuse my ignorance, I am attempting to wire a 2 pole QO shunt trip breaker that will provide power to a sub panel that contains breakers for outlets in a commercial kitchen. My question is,what will my wiring be coming from the micro switch in the Ansul module to the breaker?Appears to be 3 contacts on the switch, (1) N/O, (1) N/C, and (1) C. Do I take 120Vpower to the switch and then just run a "signal) wire back to the breaker? I've never dealt with this before, only been doing electrical work for a couple of years. Thanks.
 

iwire

Moderator
Staff member
Location
Massachusetts
I will assume you have two leads hanging out of the breaker?

If so land one of these on the neutral bar, run the other out to the Ansul switch using the normaly open contacts, (N/O and C) now back to the same panel with the shunt and feed the circuit from a breaker that will always be on.

Done.
 

brian john

Senior Member
Location
Leesburg, VA
For some reason two conductors hanging out the side of a circuit breaker baffle electricians..

In the case of a shunt trip these two conductors lead to a coil this coil when energizes pulls in, activating the trip mechanism for the CB. Think of those two wires as feeding a light fixture, one is the neutral and the other is the phase/hot/energized conductor. You have to turn the load (light) on and when the load (light) goes on the circuit breaker opens. Any number of contact closures can be used to operate this shunt trip

There are other cases where there are two or more conductors hanging out the side of a circuit breaker, one is under voltage release, this has to be energized to close the circuit breaker and the circuit breaker opens when the UV relay is de-energized.

The other case is AUX (auxiliary) contacts , sometimes two conductors but usually 3 or 6 maybe 9 conductors a common, a NC (normally open contact) or a NC (normally closed contact).

Always check the side of the CB for type of accessories when you have extra conductors just hanging there, for type of accessory and voltage rating.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
Nizak, think of a shunt-trip breaker as a remote-controlled-tripping breaker. A voltage sent to the breaker will cause it to trip, much like a GFCI breaker. Some include auxillary contacts that are often used to immediately remove the tripping voltage to avoid burning out the tripping coil.

As for wiring the suppression system to it, as mentioned above, one of the wires simply gets connected to the panel's neutral bus. The second should connect to a contact on the Ansul's micro-switches that receives power only when the supression system trips.
 

jim dungar

Moderator
Staff member
Location
Wisconsin
Occupation
PE (Retired) - Power Systems
I believe (?) a QOxxx-1021 shunt trip breaker has screw terminals for the trip not wires.
 

celtic

Senior Member
Location
NJ
nizak said:
Excuse my ignorance, I am attempting to wire a 2 pole QO shunt trip breaker that will provide power to a sub panel that contains breakers for outlets in a commercial kitchen. My question is,what will my wiring be coming from the micro switch in the Ansul module to the breaker?Appears to be 3 contacts on the switch, (1) N/O, (1) N/C, and (1) C. Do I take 120Vpower to the switch and then just run a "signal) wire back to the breaker? I've never dealt with this before, only been doing electrical work for a couple of years. Thanks.

Is there a requirement that all equipment "under the hood" be disconnected simulataneoulsy on alarm/incident?

Here are two similar threads from recent days;
Commercial exhaust hoods and make up air.

Shunt trip breakers
 

480sparky

Senior Member
Location
Iowegia
celtic said:
Is there a requirement that all equipment "under the hood" be disconnected simulataneoulsy on alarm/incident?

I think that's if it's a wet suppresion system. If it's dry, I don't think it's required.
 

iwire

Moderator
Staff member
Location
Massachusetts
480sparky said:
I think that's if it's a wet suppression system. If it's dry, I don't think it's required.


What kind of wet suppression system is used under a hood? :confused:

All the ones I have done where 'dry' chemical systems and all sources of fuel/ignition had to be cut off.

It is hard to keep a pan of oil extinguished if the electric element under it keep pumping heat into the oil.
 

celtic

Senior Member
Location
NJ
480sparky said:
I think that's if it's a wet suppresion system. If it's dry, I don't think it's required.
I don't think you want "wet" under the hood....grease spatters and flames and that sort of occurance.


Although Ansul does make a "wet" product:
R-102? Restaurant Fire Suppression Systems
The ANSUL? R-102? Liquid Agent System continues to be the #1 protector of today?s kitchen equipment.

R102_m.jpg



...I have only see the "dry" type.
 

LarryFine

Master Electrician Electric Contractor Richmond VA
Location
Henrico County, VA
Occupation
Electrical Contractor
brian john said:
Larry:

I see no coorelation between a shunt trip circuit breaker and a GFCI, other that they are both OCP devices.
My bad. I used a poor comparison, but I meant that the breaker can be tripped "remotely" without a fault/overload occurance or with manual handle operation.

GFCI's, for example, can be tripped by pressing the test button or by using a GFCI tester or with a solenoid voltage tester, and the handle moves.

"Remote control" :rolleyes:
 

480sparky

Senior Member
Location
Iowegia
iwire said:
What kind of wet suppression system is used under a hood? :confused:

All the ones I have done where 'dry' chemical systems and all sources of fuel/ignition had to be cut off.

It is hard to keep a pan of oil extinguished if the electric element under it keep pumping heat into the oil.

Last 4 hoods I've worked on were wet systems.

It's been years since I've even seen a dry system...

The idea is not to turn the electric off to prevent reignition of a pan of oil (most coomercial stoves are gas anyway, so the gas sets shut off when the systme discharges), it's to prevent any liquids from becoming energized.

As I understand it, most Ansul-type systems are completely drained within seconds... they don't continue to dispense the suppresion agent for long periods of time like a sprinkler system does water.
 
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celtic

Senior Member
Location
NJ
480sparky said:
The idea is not to turn the electric off to prevent reignition of a pan of oil (most coomercial stoves are gas anyway, so the gas sets shut off when the systme discharges), it's to prevent any liquids from becoming energized.
Fryers, steamers, warming draws, etc can be electric.
The kitchen I finished last month even had refrigerators, steamers and a skillet all "under the hood"...all electric...all shunt trip CBs...and GFCI's as required.


Yea...it was a LONG front line :)

On this particular job, the gas for the 12 burner range had a solenoid valve that would shut down the gas when there was an "incident"...it also did NOT have electronic ignition :-?. I guess gi-normous ranges are different.
 

iwire

Moderator
Staff member
Location
Massachusetts
480sparky said:
The idea is not to turn the electric off to prevent reignition of a pan of oil

Actually it does has to do with re-ignition as you point out the Ansul system is depleted quickly and re-ignition can not be dealt with.

Remember the fire triangle.

Oxygen, Fuel, Heat.

You must take away the source of heat if you plan on keeping the fire out.

Why must we take away the heat?

Because the fuel will still be there and the oxygen will come back once the suppression system is empty.

(most commercial stoves are gas anyway, so the gas sets shut off when the system discharges),

Yes I agree most are, then again I work at quite a few locations that are not gas,....electric deep fryers, electric pizza ovens, even electric chicken roasters. etc.

it's to prevent any liquids from becoming energized.

I don't believe that has anything at all to do with it, I think your assuming that.

Have you ever seen a requirement to shut down the electricity automatically for any other wet system application other then maybe a DATA room?

Take a main electrical room with a wet system in the room, must we shut down the gear upon activation of a sprinkler head?
 
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brian john

Senior Member
Location
Leesburg, VA
Take a main electrical room with a wet system in the room, must we shut down the gear upon activation of a sprinkler head?

NO, but I have seen other drastic measures taken, NEMA 3R gear, drip shields on everything. The fact is when a fire or explosion occurs in an electric room with a wet system the steam permeates EVERYTHING, then the fun begins... and no practical measures exist to STOP this steam.
 

brian john

Senior Member
Location
Leesburg, VA
NO but I have investigated and cleaned up many. But Check here they have some good clips. I went to the Bussman facility in St. Louis and saw this in action my only regret is we could no blow up more stuff....

They changed their website around and not necessarly for the better IMO..But thats because I was familar with the old site


http://www.bussmann.com/
 
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