# alarm issues



## s.kelly (Mar 20, 2009)

Got an alarm at a community center where I volunteer. Making some changes and I just got the recent page of false alarms. There have been 2 glass break sensor and 2 door contact false alarms

We have had lots of storms in the 30 day period and there is heavy truck traffic on the street out front, but this seems excessive to me. It is however a leaky old building and I have heard that the contractor bases some of the alarms on the trucks.

I don't do alarms so I have nothing to base it against.


----------



## HARRY304E (Sep 15, 2010)

s.kelly said:


> Got an alarm at a community center where I volunteer. Making some changes and I just got the recent page of false alarms. There have been 2 glass break sensor and 2 door contact false alarms
> 
> We have had lots of storms in the 30 day period and there is heavy truck traffic on the street out front, but this seems excessive to me. It is however a leaky old building and I have heard that the contractor bases some of the alarms on the trucks.
> 
> I don't do alarms so I have nothing to base it against.


Sound's like poor connections and splices.


----------



## user4818 (Jan 15, 2009)

The glass break sensors can have their sensitivity dialed down. There is also a test you can do to see if they are operating correctly, at least on the Ademco stuff that I use. I'm sure the DSC, Napco, Bosch, etc stuff is the same.


----------



## zwodubber (Feb 24, 2011)

Did you replace the wiring from the pull stations to the main unit? If so is it run in conduit?

We had a call at a commercial site with alarm errors showing up. It was originally wired in 1995 with THHN in conduit. After doing continuity tests between the wire and conduit we found the culprit. It was a warehouse environment with forklifts flying around. One hit the conduit hard enough to pierce the insulation on the wire.

We ended up doing a complete rewire using fire rated four conductor through a 700,000 sq ft building. 

Even though there is only 24V running through it with a triggered alarm, these are complicated closed loop systems and finding faults between strobe/sirens and pull boxes to the main unit can be time consuming. There were 5 zones all independently monitored.

Also check the resistor at the end of the loop if there are multiple zones, it could be that simple.

This was a Simplex Grinnell system BTW.


----------



## zwodubber (Feb 24, 2011)

HARRY304E said:


> Sound's like poor connections and splices.


If anything it would be the connections, we did not splice any wires in the alarm system. All home runs to each zone and the connections were at the pull boxes and strobe/siren units.

Splices will fail here as it is a life saving device.


----------



## bduerler (Oct 2, 2009)

zwodubber said:


> If anything it would be the connections, we did not splice any wires in the alarm system. All home runs to each zone and the connections were at the pull boxes and strobe/siren units.
> 
> Splices will fail here as it is a life saving device.


They are talking about a burg system:laughing: not fire. I agree with your assessment for the FA if that was the subject. 

Check the magnets on the door contacts, it is possible they aren't in line with the contacts. As for the glassbreaks take your normally closed wire off the contact and twisi it with the common. Leave your 12 volt power on the glass break. If the circuit closes the wire is good if not than you might have a bad device or connections. You can do the same thing for a door contact, just twist the wires together out in the field and if it clears good wire, could be bad contact or the magnets arnt in line. If it doesnt clear run a new wire. If you replace the contact always replace the magnet you never know if its getting weak or not.


----------



## BBQ (Nov 16, 2010)

zwodubber said:


> Splices will fail here as it is a life saving device.


Say what?


----------



## zwodubber (Feb 24, 2011)

bduerler said:


> They are talking about a burg system:laughing: not fire. I agree with your assessment for the FA if that was the subject.


:laughing: oh well, now the OP may know what to look for on any fire alarm errors...


----------



## bduerler (Oct 2, 2009)

BBQ said:


> Say what?


 As far as I know you can splice a FA system as long as it is in a labeled splice box and painted red. Thats what the AHJ requires here for splices.



zwodubber said:


> :laughing: oh well, now the OP may know what to look for on any fire alarm errors...


:laughing: yes he will


----------



## LARMGUY (Aug 22, 2010)

I'm assuming as an electrician you have an alarm license and or the building in question is in an area that requires no license. Just saying if you mess with it and something happens...

Check the door contact gap too. Put your meter on continuity and test the conact terminals with the wires off. Slowly open and close the door and notice the gap. Go outside, shut the doors and push on the area of the door that the contact is mounted. see if the contact changes state. 

As for the glassbreaks, they have a test mode you can use to set them.


----------

