120v Tamper Switch?

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amps88

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This has everyone confused, even our Fire Alarm Technician.

In on panel in a dining facility there is a 20A breaker indicated for a tamper switch and one for the PIV.

Why would someone run 120v to devices on the fire alarm loop?
 
I'm just guessing here...

I'm just guessing here...

And no, I haven't seen this done myself, but someone wanted a buzzer, bell, or light to go off (maybe at a security shack?) if the water was shut off. I'm assuming that the supervisory switches have 2 sets of contacts.....some do and some don't. Are these devices also connected to a fire alarm panel?
 
Yes they are. There is a gas soleniod control also but it is powered by another panel.
There is no indication of the two circuits on the kitchen equipment electrical, general electrical or fire alarm drawings.
I have sent an RFI to COE about this. I was just wondering if anyone else had heard of such a thing.
Thanks
 
Don't know if this helps or not...

I've seen 120V wired to a fire sprinkler flow switch, then this went to the main breaker to turn off power to the building. So fire sprinkler head pops, water flows in pipe, flow switch activates, power to building cut.
 
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Some sort of home-brew annunciation is the only reason I can think of to run 120V to a post indicator valve. Probably nothing wrong with it, but it is weird.
 
In my area, we have a local code that requires an exterior bell to ring during water flow. This is accomplished by using a 120 volt bell, controlled by a flow switch, or a mechanical bell that operates by the actual water flow.
 
peter d said:
In my area, we have a local code that requires an exterior bell to ring during water flow. This is accomplished by using a 120 volt bell, controlled by a flow switch, or a mechanical bell that operates by the actual water flow.
Click to expand...
A typical flow switch has 2 sets of contacts, 1 for the Fire Alarm system and 1 set for a 120vac Horn / strobe to help the Fire Fighters locate the Siamese Connection on the building.
So could it possibly be for locating the Post indicator valve ?
 
Stallzer said:
A typical flow switch has 2 sets of contacts, 1 for the Fire Alarm system and 1 set for a 120vac Horn / strobe to help the Fire Fighters locate the Siamese Connection on the building.
Click to expand...

That's one way to do it as well. Local codes and practices vary when it comes to this stuff, but usually there is some kind of outdoor notification with sprinkler systems.
 
120v tamper switch

120v tamper switch

Billy_Bob said:
Don't know if this helps or not...

I've seen 120V wired to a fire sprinkler flow switch, then this went to the main breaker to turn off power to the building. So fire sprinkler head pops, water flows in pipe, flow switch activates, power to building cut.
Click to expand...


Could it be because the said circuits are located in the emergency panel that would be run off a generator in case of a power loss? The Fire Alarm Control panel is fed from a different sub-panel.
 
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I was thinking about this one this afternoon.....

I was thinking about this one this afternoon.....

Billy_Bob said:
Don't know if this helps or not...

I've seen 120V wired to a fire sprinkler flow switch, then this went to the main breaker to turn off power to the building. So fire sprinkler head pops, water flows in pipe, flow switch activates, power to building cut.
Click to expand...

Are you sure that's what you were looking at?

You'll have to forgive me....while I've seen shunt trip coils used to trip a breaker to kill power to elevators (once the feedback signal has come back from the elevator controller indicating that the elevators are recalled and the doors are held open), and in computer rooms to shut down mainframes, incorporated into the suppression system, the concept of using one to shut off power to a building is new to me....

So, have there been many .... 'incidents' .... taking place during the required periodic testing of this particular system? Please tell me its not a hospital or a air traffic control tower or a nuclear power plant, or one of those nightclubs that gets packed to the doors on the weekends.....
 
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mdshunk said:
Some of these replies make me think some guys don't know what a PIV valve is. It has nothing to do with indicating flow.
Click to expand...

I know exactly what a PIV valve is. But going off topic was far more interesting. :D
 
MichaelGP3 said:
Are you sure that's what you were looking at?

You'll have to forgive me....while I've seen shunt trip coils used to trip a breaker to kill power to elevators (once the feedback signal has come back from the elevator controller indicating that the elevators are recalled and the doors are held open), and in computer rooms to shut down mainframes, incorporated into the suppression system, the concept of using one to shut off power to a building is new to me....

So, have there been many .... 'incidents' .... taking place during the required periodic testing of this particular system? Please tell me its not a hospital or a air traffic control tower or a nuclear power plant, or one of those nightclubs that gets packed to the doors on the weekends.....
Click to expand...

I'm darn sure the flow valve tripped the main breaker because my job at the time was testing fire alarms and I was testing the flow switch to be sure if one head popped, this would activate the fire alarm.

So when I tested the alarm by opening the test valve, the alarm triggered and the power went out!

Then I investigated and saw that the flow switch was also wired to the main breaker! This was a large national retail chain-store.

This store had refrigeration equipment to keep food for sale cold as well as A/C... I informed my boss about this unusual set-up with the fire sprinkler flow switch, then he met with his boss, etc.

This resulted in a letter to the retailer that we could no longer test the fire alarm flow switch unless they wrote us a letter saying we not responsible to any damage to any of their equipment (refrigeration) due to power loss from testing the alarm.
 
Billy_Bob said:
I'm darn sure the flow valve tripped the main breaker because my job at the time was testing fire alarms and I was testing the flow switch to be sure if one head popped, this would activate the fire alarm.

So when I tested the alarm by opening the test valve, the alarm triggered and the power went out!

Then I investigated and saw that the flow switch was also wired to the main breaker! This was a large national retail chain-store.

This store had refrigeration equipment to keep food for sale cold as well as A/C... I informed my boss about this unusual set-up with the fire sprinkler flow switch, then he met with his boss, etc.

This resulted in a letter to the retailer that we could no longer test the fire alarm flow switch unless they wrote us a letter saying we not responsible to any damage to any of their equipment (refrigeration) due to power loss from testing the alarm.
Click to expand...


at the customer's request, I have wired such systems, but we always installed a swith in the system to prevent the power trip during "routine test". The switch was always double-pole and activated some type of supervisory alarm when switched to eliminate it being accidentlly left "off"
 
amps88 said:
This has everyone confused, even our Fire Alarm Technician.

In on panel in a dining facility there is a 20A breaker indicated for a tamper switch and one for the PIV.

Why would someone run 120v to devices on the fire alarm loop?
Click to expand...

One question for the OP: What is the rest of the fire alarm system like? We have old buildings in our area that have completely 120v ac fire alarm systems. The only portion not 120v is the relay box next to the panel that sends a make/break signal over a dedicated phone line to the alarm center.

:-?

Mike
 
The system is Honeywell, Class "A" AE Loop wiring. The only 120v on FA drawings is for the Control Panel. The building is a new Dining Facility located on an army post.
We are beginning to think it is just one of the many "oops, that shouldn't be there" that we find on the drawings we were given to work with.
 
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