ansul system wiring

[mgonzalez1031]

hey guys, need some help. I am currently working in tx. on a small restaurant and nee d to connect a vent hood. First of all i have never done a ansul sys. before, so please forgive if some of the questions sound dumm.
I have a single vent and a supply(fresh air)and lights. the lights and supply are required to shut down when the ansul system is activated. the system is also a mechanical setup,so it has no low voltage control circuit.the question i have is where do the 2 leads of the shunt trip breaker land? do i just need a regular breaker or do i need a shunt trip breaker? Your help would be greatly appreciated :grin:

 

[mdshunk]

Isn't there a micro switch in the upper right hand corner of the ANSUL cabinet? Never saw one without that microswitch.

Here's an ANSUL question from a couple of days ago the might clear things up a little.
http://www.contractortalk.com/showthread.php?t=16291

 

[mgonzalez1031]

yes there are two micro switches. rated for 20a ac

 

[emahler]

you need those...on the backside of the cover will be a simple schematic, it'll tell you everything you need to know. good luck.

 

[mgonzalez1031]

there are no schematics behind the cover

 

[LarryFine]

Here is a simple way I came up with for controlling both fans using only one microswitch, relieving the second for other stuff. The loads may be either relays or the fans themselves if within the switch rating. Your colors may vary:

Now you have the second microswitch to use for the lighting, shunt-trip breaker(s), and/or relays. Today, I added three relays (aka contactors) to shut down the electrical equipment under a large hood.

Two 3p, 30a relays de-energize a pair of 3-phase convection steam ovens, and a 4p, 20a relay de-energizes three 20a receptacle circuits, with the fourth pole reserved for future use.

I simply added these three relays to the intake-fan contactor, which is controlled by the modification I drew above. When we split the original intakes and exhausts, I ran a 12-3 to replace the 12-2, so I had the 12-2 to control these new relays.

You really need to know the full extent of the requirements, which the fire-suppression guys should know.

In one county, we need to energize the exhaust (whether already on or not), de-energize the intake (ditto), extinguish the lighting, de-energize anything electrical under the hood, shut off the gas via a solenoid valve, and energize a horn/strobe unit.

Plus, the gas solenoid must further be controlled by a manually-reset latching relay, so resetting the Ansul system will not energize the gas solenoid. They apparently want you to be ready to re-light the pilots.

The real kicker is that even manually turning off the exhaust fan must do everything the system tripping does, except for the supression and the horn/strobe unit. They have to reset everything every time they turn off the fans.