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Posted By: bot540 Ansul System - 11/08/06 06:54 PM
I am doing a commercial kitchen with an ansul system for the first time and had a few questions. The inspector want all power to the hood and exhaust fans to shut down. How is this usually acomplished, with contactors and a low voltage signal? Does anyone know where I can find wiring diagrams?
Thanks.
Posted By: iwire Re: Ansul System - 11/08/06 07:20 PM
The ansul panel will have electrical contacts in it, usually a few SPDT micro switches.

The most common way I handle it is by the use of shunt trip breakers controlled at 120 volts through the ansul contacts.

Be sure to find out exactly what needs to be shut down.

In my area the power to the appliances under the hood and the make up air supply shut down but exhaust fans and lights stay on.

In other areas they want all power off, before you waste time and money find out for sure what your AHJ wants.
Posted By: renosteinke Re: Ansul System - 11/09/06 12:56 AM
I agree with Bob... work closely with your fire guy on this one.

The trip mechanism will usually have two sets of contacts. One set is used in the "normally open" position by the alarm guy; the other is for you.

I use the "normally closed" contacts to interrupt power to my contactor coils. System trips, coils stop working, contactors open, stuff shuts down.

I have had the issue of the exhaust fans go both ways. The make-up air, any power under the hood, hood lights, and the gas valve (if electric- most are mechanical) all get shut off.

Usually, I will use an 8x8 gutter to mount my contactors in. I do this, as usually the power to the various items comes from different panels.

The coils really ought to be on their own dedicated circuit. This is both because it makes it easy to test the system, and you really don't want any nuisance tripping. Lose power, everything under the hood gets shut down.

As for the circuits being interrupted, I cut into them wherever it's most convenient. This could very well be at the panel, and nowhere near the appliance at all.
Posted By: HCE727 Re: Ansul System - 11/09/06 01:40 AM
BOT, I have something from ANSUL, if you have a fax, I will fax it to you. E-mail me.
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