Question on existing wiring

Grayson5

New Member
Hi,
 
I am in the process of installing an ELK-M1 to replace the existing (not hooked up) alarm system in the house I recently purchased.  I am pretty much an amateur when it comes to wiring and I had a question on how the existing wiring is hooked up for the old system.
 
Please see the picture below.  I assume that this is how individual door or window sensors were wired together to form one zone to connect to the old control board.  Is this correct?  If so, why are the negative (black) wires connected to the positive (red) wires.  Forgive the ignorance, I am just trying to learn.
 
Also, is it OK to keep them together and hook into the M1 for one zone?
 
[sharedmedia=gallery:images:576]
 
wiring-1.jpg
 
Thanks for the help,

John
 
It looks like three zones are wired in series so they can all use just one security channel on the controller.  If any of the zones 'open' the channel would show violated.
 
This can get a bit tricky if EOL's are used as only one of the zones (usually furthest from the controller) should use the resistor.
 
You should get a multimeter and test each zone out individually to get a feel for how they work, then test as an integrated series circuit.  This would also double check the wiring.
 
Refer to my How To on installing a home security system for details.
 
Grayson5 said:
Hi,
 
 why are the negative (black) wires connected to the positive (red) wires.  Forgive the ignorance, I am just trying to learn.
 
Also, is it OK to keep them together and hook into the M1 for one zone?
 
 
 
attachicon.gif
wiring-1.jpg
 
Thanks for the help,

John
 
In reality it can be wired any way since standard door and window contactors don't have polarity.  But by convention you use the red for power out to the device and black as the power returning from the device to close the loop.
 
So when connected multiples in series, that means the black returning power from the first one is the source of outgoing power to the next zone, and so forth.
 
The odds are damn near zero that you have any eol resistors on those zones.  If they home runned the wires then that would typically mean that they at least considered making them 3 different zones.  And to have eol resistors, then only one of the 3 zones could have had the resistor.  And this would have meant that if you separate the 3 zones, then you would now have a hodge podge of zones with and without eol resistors.  
 
In summary, that chances are nearly 100% that there is no eol resistor anywhere on that loop and that you could either plug the batch of 3 into a single zone or break them up into 3 separate zones.
 
Elk makes this easy.  Just hook it up whichever way you want (series or individual to 1 or 3 zones). Connect to Elk RP and click on status page.  It will display the voltage on each zone and you will know from that if they are just simple open/close zones or eol resistor zones.  My bet is simple open/close.
 
Thanks! I was able to get the first 2 zones hooked up today and on my way to hooking up more, plus the output siren.
 
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