wiring shunt trip breakers

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riversidefab

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I have 6 shunt trip breakers in the panel I'm wiring for a commercial kitchen counter located under a hood. This is the first time I have used shunt trip breakers in a panel. Can I "daisy-chain" the trip wires from my shunt trip breakers inside the electrical panel and run only two trip wires out of the panel to a junction box for the electrician on site to wire to the fire suppression system?
 
Re: wiring shunt trip breakers

Electrically no problem. However, will the fire suppression equipment circuit/switch handle that much current? Do all of the breakers need to operate at the same time?
 
Re: wiring shunt trip breakers

Maybe. If all shunt trip coils use the same control voltage (120VAC, 24VDC, or ??) you could parallel (not series, not daisy chain) the trip coil wires together and only run two wires to the fire suppression panel.

Things that might affect the installation:

Are all trip coils the same voltage?
Where is the tripping power source - another panel, a breaker in the same panel, the fire alarm system?
Are the shunt trips energize-to-trip or de-energize to trip?
Are the fire panel output contacts rated for the trip coils? current and voltage? (This is usually not a problem.)
Should all six loads trip for any fire or does the fire panel have multiple outputs designed to shut down just an affected zone?
 
Re: wiring shunt trip breakers

Thank you for the fast reply.

Yes, there are 5 breakers that trip at the same time (these equipment are located under one hood) and 1 breaker is located under another hood.

We're not sure what the fire suppression switch can handle. Under the equipment schedule, the fire suppression system is listed as having 20-amp service. So...I guess my question about this is, what amperage does it take to trip a shunt trip breaker? does it take a full 20 amps to trip the shunt on a 20-amp breaker?

We have (2) 30-amp shunt trip breakers and (3) 20-amp shunt trip breakers for the equipment under one hood. Additionally, there is (1) 30-amp shunt trip breaker for the piece of equipment under the second hood. So, we were thinking of tying the 5 trip wires that are for one hood together and running 2 wires out of the panel to the junction box for these. Then, just have the trip wires for the single breaker under the other hood wire directly from the panel to the junction box.
 
Re: wiring shunt trip breakers

You need to be concerned wth the rating of the switching device not the circuit that feeds it. Ask the equipment manufacturer

If these are Square D QO breakers, each 120VAC trip coil takes about 24VA.
 
Re: wiring shunt trip breakers

riversidefab,

The shunt trip coil uses very little power,I can't see 6 STCB giving you a problem.

The ansul system dry contacts are normally rated for 20a and you'll be lucky to draw 2a.

Where ever the control power originates make sure you bring the neutral all the way to all the STCB.
 
Re: wiring shunt trip breakers

Shunt trip breakers are not needed for this.
simply run the circuits thru contactor polls (how ever many you need) and run the control circuit thru the micro switch ( common/NC)located in the Ansel bottle encloser (which is rated at 20 amps).
When the system is activated, the control circuit for the contactor drops out thus disconnecting the circuits.

It's the cheapest way and it passes code.
 
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