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Posted By: Peter Shunt trip breakers - 08/17/06 12:39 AM
I was hooking up an Ansul system today with a shunt trip breaker. I connected the shunt trip to the normally closed contacts from the Ansul system. It seems that every time I turn on the breaker for the Ansul system, both of the pizza oven breakers trip. Should I attach to the normally open contacts?
Should I wire the two pizza ovens in parallel or series?
~Peter
Posted By: togol Re: Shunt trip breakers - 08/17/06 01:55 AM
around here, once the Ansul ring is pulled,
EVERYTHING electrical on
the cooking line must be de-energized,

the gas valve must close ,

the MUA for the hood is shut down,

and the hood exhaust fans shall continue to run....

is the Ansul system cocked ? it sounds like it is tripped and needs to be reset.

unwire the ansul switch and reset the shunt breaker , that should tell you

pizza ovens in parallel or series???
Posted By: Peter Re: Shunt trip breakers - 08/17/06 03:22 AM
The Ansul system is cocked.
What I mean by series/paeallel is there are two, three pole breakers, each with its' own shunt trip mechanism [takes up on breaker space]. I wired these in series instead of parallel.
What I need to know is what trips the shunt trip? Is it the presence of voltage or the absence?
~Peter
Posted By: Roger Re: Shunt trip breakers - 08/17/06 10:14 AM
The shunt trips work upon applied voltage.

You will need to wire two breakers in parallel.

One side of the shunt coils will wire to a neutral or neutral bar, (this is assuming 120 v shunt trip units) the other sides get the voltage through the Ansul switch. You will feed the Ansul common with 120 v and wire your switch leg to the open switch conductor when the Ansul system is cocked.

Roger

[This message has been edited by Roger (edited 08-17-2006).]
Posted By: Larry Fine Re: Shunt trip breakers - 08/18/06 12:56 AM
Just an aside: For anyone who needs it, I came up with a way to interconnect the intake and exhaust fans to the control box using only 3 wires.

There are two advantages: (1) freeing up the second micro-switch for use with shunt-trips or other purposes; (2) being able to use simpler wiring methods (MC, etc. as required).

It can easily interface with existing wiring. Of course, anything other than 120v motors will need relays/contactors to use this method.

Before:

[Linked Image from fineelectricco.com]


After:

[Linked Image from fineelectricco.com]
Posted By: XtheEdgeX Re: Shunt trip breakers - 08/18/06 03:20 PM
Normally Open
Posted By: Peter Re: Shunt trip breakers - 08/19/06 01:47 AM
Today I changed from serial to parallel. This seems to make sense. I had already changed from the N.C. contacts to the N.O. contacts.
Thank you for your adviCe.
~Peter
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