looking for a solution of combined use the alarm lines in home

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
Hi,
there are alarm sensor for each door in my home, and I can check the doors status from a panel.

Is that possible to used the lines for some other usage simultaneously ? like the lights on/off sensor, and even control the light by the lines?
Thanks for help.
Adam
 

DickCappels

Joined Aug 21, 2008
8,671
You would have to run a pair of wires from every sensor to your status panel. Usually, when installed by professional installers, many if not all the sensors in the home are wired in series. Or is your wireless?

It might be possible to send more than one signal through the wires but that depends on how the sensors are wired and the exact nature of the equipment connected.
 

MisterBill2

Joined Jan 23, 2018
11,556
It is not likely that you can add a second function to those alarm switch wires without a major redesign of the alarm input section. That is mostly because the sensors are normally closed switches in a series loop. Sensor IDentification would be by means of a medium value resistor across each switch. Thus only open sensor switches are identified.
Adding additional sense functions will require changing from a series loop to an array of digitally interfaced sensor branches, with every sensor having a unique address. Sowhile it can be done, it requires a lot more circuitry at every sensor.
Wireless schemes already include that, along with the benefit of needing battery replacements for every sensor interface.
 

Yaakov

Joined Jan 27, 2019
5,476
Even if your sensors are all wired with home runs, alarms circuits are going to be supervised meaning they are designed in such a way to detect tampering. This can be done different ways but is usually a matter of a fixed resistance at the end of the loop so that changes can be detected.

In principle since the loop is probably a DC circuit, you could superimpose an AC signal for your use that is capacitively coupled to the loop and use it for digital communications to that point. This would require a lot of careful design and testing to the point where it is probably cheaper and easier to run new wire.

This idea should work even on loops with more than one sensor, but also note that if a NC switch in the loop opens, you will loose that loop for your auxiliary purpose so it‘s probably not very useful even if you can do it.
 

MisterBill2

Joined Jan 23, 2018
11,556
Even if your sensors are all wired with home runs, alarms circuits are going to be supervised meaning they are designed in such a way to detect tampering. This can be done different ways but is usually a matter of a fixed resistance at the end of the loop so that changes can be detected.

In principle since the loop is probably a DC circuit, you could superimpose an AC signal for your use that is capacitively coupled to the loop and use it for digital communications to that point. This would require a lot of careful design and testing to the point where it is probably cheaper and easier to run new wire.

This idea should work even on loops with more than one sensor, but also note that if a NC switch in the loop opens, you will loose that loop for your auxiliary purpose so it‘s probably not very useful even if you can do it.
Good points Yaakov! I had not considered a wired ac communication scheme on top of the DC loop. And such a system can certainly be powered by loop current. It might even be possible to add it to the existing system if the loop current is adequate. BUT such an addition would require the design and build of some rather complex additional circuits in the senor end a well as large additions to the control box end. And such a system might require shielded conductor pairs to each monitored point.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
You would have to run a pair of wires from every sensor to your status panel. Usually, when installed by professional installers, many if not all the sensors in the home are wired in series. Or is your wireless?

It might be possible to send more than one signal through the wires but that depends on how the sensors are wired and the exact nature of the equipment connected.
Thanks.
its no easy to figure out how the wiring line goes. how to know are sensors in series or not?
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
It is not likely that you can add a second function to those alarm switch wires without a major redesign of the alarm input section. That is mostly because the sensors are normally closed switches in a series loop. Sensor IDentification would be by means of a medium value resistor across each switch. Thus only open sensor switches are identified.
Adding additional sense functions will require changing from a series loop to an array of digitally interfaced sensor branches, with every sensor having a unique address. Sowhile it can be done, it requires a lot more circuitry at every sensor.
Wireless schemes already include that, along with the benefit of needing battery replacements for every sensor interface.
Thanks.
Seems I'd better use wireless.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
Even if your sensors are all wired with home runs, alarms circuits are going to be supervised meaning they are designed in such a way to detect tampering. This can be done different ways but is usually a matter of a fixed resistance at the end of the loop so that changes can be detected.

In principle since the loop is probably a DC circuit, you could superimpose an AC signal for your use that is capacitively coupled to the loop and use it for digital communications to that point. This would require a lot of careful design and testing to the point where it is probably cheaper and easier to run new wire.

This idea should work even on loops with more than one sensor, but also note that if a NC switch in the loop opens, you will loose that loop for your auxiliary purpose so it‘s probably not very useful even if you can do it.
Thanks.
BTW. my alarm system is not actively in use. it just shown me the doors status for me.
I was thinking maybe can borrow the I2C idea, assign each node an address? I can use wireless. which way better and easy?
 

DC_Kid

Joined Feb 25, 2008
924
The only way one wire works is using digital method, addressable components on 1-wire bus.

Thanks.
Seems I'd better use wireless.
Be warned about using WiFi for "critical" or "protection" systems. Very simply 2.4G or 5G wifi jammers will disable your wifi enabled wifi system, rendering it useless. Ring, SimpliSafe, ADT, etc , wifi systems are a joke. If it's running a wifi alarm system, I can disable it from the street.
 

MisterBill2

Joined Jan 23, 2018
11,556
One more strike against wireless links. I had not considered the jamming aspect, that will indeed be a possibility. I know that the microwave oven has interfered with wireless internet connections on occasion.
 

Yaakov

Joined Jan 27, 2019
5,476
Thanks.
BTW. my alarm system is not actively in use. it just shown me the doors status for me.
I was thinking maybe can borrow the I2C idea, assign each node an address? I can use wireless. which way better and easy?
The the alarm system isn't important, the first thing I would do is determine if you are dealing with loops or home runs. If the latter, you can do a lot of things pretty simply, if the former, you will have to be more clever.

Yes, potentially you could use some sort of bus arrangement like Dallas Semi (now Maxim) 1-Wire bus. This has some limitations, though. With very good cabling (CAT7) you can get about 100m but you are probably dealing with relatively poor cable. It might not even be a twisted pair. In that case you'd need to design something to work over the wiring you do have, though the 1-Wire might still be used.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
The the alarm system isn't important, the first thing I would do is determine if you are dealing with loops or home runs. If the latter, you can do a lot of things pretty simply, if the former, you will have to be more clever.

Yes, potentially you could use some sort of bus arrangement like Dallas Semi (now Maxim) 1-Wire bus. This has some limitations, though. With very good cabling (CAT7) you can get about 100m but you are probably dealing with relatively poor cable. It might not even be a twisted pair. In that case you'd need to design something to work over the wiring you do have, though the 1-Wire might still be used.
Thank you Yaakov.
It is a very old system of DSC pc3000, how to find if the sensors with loops or home runs please?
 
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Yaakov

Joined Jan 27, 2019
5,476
Thank you Yaakov.
How to find if the sensors with loops or home runs please?
Probably the easiest way will be to look in the alarm panel and see what is connected, If it is home runs there will have to be a wire for each sensor, if not, there will be fewer.
 

DC_Kid

Joined Feb 25, 2008
924
Thank you Yaakov.
How to find if the sensors with loops or home runs please?
Count how many pairs of wires are in the alarm control panel. Then count how many sensors. Run the math.
I know of no std alarm wiring using loop or bus. Most installs are home-runs using one or two pair wire. It's a non-efficient use of copper, but that's the wasteful way they do it.
 

Tonyr1084

Joined Sep 24, 2015
6,861
If your panel has two wires for doors and two wires for windows and two wires for motion detectors or beams then you have series loop systems. If you have three doors and six wires for the doors then each is a home run setup. 10 windows will have a pair of wires for each window (20 wires). Motion detectors also will have at least two wires per sensor. You may also possibly have two wires to provide power for each sensor or sensors.

In short - a lot of wires in the panel you have home runs. Fewer wires - likely series loops. Give us a picture of the inside of the box and we can tell you in a heart beat.
 

ElectricSpidey

Joined Dec 2, 2017
2,140
This is the first time I have heard of zones being referred to as "home runs" my system has 8 zones, which are all "loops", and you can place as many sensors/switches/whatever on each loop/zone.
 

Yaakov

Joined Jan 27, 2019
5,476
This is the first time I have heard of zones being referred to as "home runs" my system has 8 zones, which are all "loops", and you can place as many sensors/switches/whatever on each loop/zone.
Zones are orthogonal to home runs. Alarm sensors can be organized in zones with or without loops, though loops are usually called "zones" from the users perspective and can't be more atomic than the loop.
 

Thread Starter

LAOADAM

Joined Nov 21, 2018
807
I think it is not a loop.
I did't check the the keypaids yet, shoud it connect to all wires as this panel?
Also how to add new sensors now?

33.JPG
 
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