Alarm panels and sensors. Who has put resistors at EOL for residential?

May 1, 2019
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Reno, NV
I have a new DSC 1832 panel I have yet to fire up (waiting on power supply and battery). Recessed sensors for windows and doors all set.
However, before I close up all the swiss cheesed drywall I cut out, the EOL resistors come to mind. It seems, they are great for additional security in a business environment. But are they needed in residential? These would be resistors that are inserted near the senors, not the box.
 
EOL devices / resistors are placed at the end of the circuit when you want the circuit to be supervised for residential or commercial.
They are not "needed" for either unless it is a life safety circuit ( fire alarm ) and then that depends on the AHJ.
It's purpose is to provide the panel with a notification of when there is a trouble within the circuit. ie. a sensor failure, fault or short.
 
so now the question is... should I or should I not? :) I think I will. Doesn't hurt. Will take a little bit of time to add in some troubleshooting insurance but I only get 1 shot at a thumbs up or thumbs down. Might as well get it out of the way.
 
It's not a bad idea to have and can save a lot of time troubleshooting the circuit... Just keep in mind you dont want to bury it in the wall.. you will regret it later..
 
I have recessed window/door sensors. Thought the EOL resistors are to be inches before the sensor.
 
They only need to be at the end of the last sensor in the circuit.. ( should be) Many like to put them ITP- in the panel - but that is not the correct location.
 
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EOL devices / resistors are placed at the end of the circuit when you want the circuit to be supervised for residential or commercial.
They are not "needed" for either unless it is a life safety circuit ( fire alarm ) and then that depends on the AHJ.
It's purpose is to provide the panel with a notification of when there is a trouble within the circuit. ie. a sensor failure, fault or short.

My understanding is they allow you to differentiate between short circuit and fault. The panel will detect both but in a commercial environment it's necessary to detect the difference due to the more sophisticated methods burglars may use.
 
They only need to be at the end of the last sensor in the circuit.. ( should be) Many like to put them ITP- in the panel - but that is not the correct location.
This guy has an interesting video on EOL resistors. At about 12 minuets in, he shows a technique using a 4 conductor wire that allows the EOL resistor to be properly placed in the panel.
 
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You are so miles ahead by having physical sensors on all of your doors and windows compared to most houses that the EOL resistor location is pretty minor point. I did all mine in the panel and have zero issues with long term use on a Honeywell system. The average home burglar is a dumb ass not some kind of mastermind.
 
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Federman...I think I saw that video of using 4 pair wire instead of two so you that you can put resistors in the alarm box. Too late for me :) Already ran 2 wire. Now to decide if putting a resistor forever behind repaired drywall is a good idea, or not so good idea.
 
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If you hide the sensor in the drywall will you have the ability to replace a bad sensor down the road or deal with a damaged wire right at the sensor right where damage is likely to happen?
 
If you hide the sensor in the drywall will you have the ability to replace a bad sensor down the road or deal with a damaged wire right at the sensor right where damage is likely to happen?
The master plan is... to attach the resistor to the back of the recessed sensor. All window/door sensors are horizontal through adjoining studs with a ... um... er... 1/2" hole? The sensor will be epoxied or glued into the hole with 5-6" slack of 2 wire in the wall. I think...if anything ever goes amiss with the sensor or resistor, I can pry it out from window/door frame and see what's going on.
I did buy a 20 pack of these for sensors:
41I7wr3-PzL._AC_SL1001_.jpg
 
I have a self-installed system as well and am using similar recessed sensors. Smart move leaving some slack so they can be pulled out if needed.

I did not go the end resistor route just for simplicity of installation. Kind of wish I had since one of my garage door sensor wires broke (it was exposed and something snagged on it at some point). Had no idea it wasn't working for quite a while before I noticed it was always reporting open. If I had those resistors it would have generated a trouble. I'd say if you can do it now, get it done!