Do all the coloured wires in an alarm mean anything?

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I've just had to fiddle around with another burglar alarm, and wondered what all those colours in the detector cables mean. There's so many different colours that start with yellow, blue, black and red in 4 core. It then gets even prettier with more colours in higher cored cable. I've never read /seen anything about that, so..
  1. Is there a standard colour code for alarm wiring, or is it made up on site?
  2. Wouldn't it be more tamper resistant if the colour scheme was random at each site?
 
No official standard as far as I am aware although some installers/companies might have their own standards. I would think most installers use black/red for 0 & 12v. As for the tampering while probably not impossible, you would need access to the cables/detectors be able to modify them while not setting off any tamper alerts and the use of resistors also helps further protect the system. Any would be burglar would also need to know what colours had been used for what purpose in order to attempt a some kind of tamper.
 
omega015, if black/red are used for power, does that imply most professional installations feature at least 6 core cable? The smallest /cheapest cable from B&Q is 4 core which would be contact circuit and tamper circuit.
 
I would hazard a guess that most use 6+ cores but it all depends on the alarm panel and detector being wired as to how many cores you need. i.e. a door contact might only need 2 wires as the zone and tamper is handled by the resistance on those two wires (using resistors in the contact itself). But that all depends if the panel uses resistance to detect zone state and isn't a basic DIY panel.
 
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We use 8 core to everything as it provides spare cores for future use. The company i work for uses a standard colour code but any colour can be used.
 
This is the little instruction leaflet inside one of the contacts I used. It's not the cheapest (grade 2), but not the most expensive:-

upload_2017-2-10_13-1-47.png


CQR in all their wisdom use red for the detection circuit. 4 core has red and you probably wouldn't use 4 core for any type of active sensor requiring power. This would suggest red & black are not for power. Perhaps there is a rule of thumb colour scheme. Hmm...
 
The SC555 does not require a power supply hence there is no Positive or Negative core assignment and Red and Blck can be used for any other purpose. In this case the manufacturer suggests red and black for the sensor but it could be any other pair of cores.
 
This is the little instruction leaflet inside one of the contacts I used. It's not the cheapest (grade 2), but not the most expensive:-

View attachment 113850

CQR in all their wisdom use red for the detection circuit. 4 core has red and you probably wouldn't use 4 core for any type of active sensor requiring power. This would suggest red & black are not for power. Perhaps there is a rule of thumb colour scheme. Hmm...
No
 
**r *****t ***e

If you don't know, get your METER and work it out

That's if you know how to use it.

The colours mean nothing, their use is down to the office/engineer who installs the system.
 
There is no standard colour code for burglar alarms, its an added security feature, just make up your own and take note.
 
Might it then be cheaper /quicker to install a standardised system then? Surely the effort of tracking the wire arrangement for each site is troublesome? If a fitter has 20 clients, it must be a pain to keep records of each installation and leads to mistakes. I'm only imagining what would happen if the mains electricity came through randomly coloured wires, or car wiring to a lesser extent.

If it saved 10% of a fitter's on site time, might that not be justification enough to standardise? Surely the finance director would push for standardisation as in other sectors?
 
Might it then be cheaper /quicker to install a standardised system then? Surely the effort of tracking the wire arrangement for each site is troublesome? If a fitter has 20 clients, it must be a pain to keep records of each installation and leads to mistakes. I'm only imagining what would happen if the mains electricity came through randomly coloured wires, or car wiring to a lesser extent.

If it saved 10% of a fitter's on site time, might that not be justification enough to standardise? Surely the finance director would push for standardisation as in other sectors?

Standardised system? For alarm wire colours there isn't one. As for grading/EN standards etc.. there is but that has nothing to do with the OP's question. Not sure why anyone would need to go to the effort to track all the wiring colour arrangements/colours of each detector. Labelling the cable & detector, zone description and detector location should be enough to maintain. You work one detector at a time and only need to know about the one your working on which should be pretty easy if its all labelled/wired up correctly. Even electricians should test circuits/wires to make sure that the wires are what they are supposed to be and don't rely on colour alone.

The finance director of such alarm company can push for whatever they want but its not up to them what colours other fitters use or what system a company has/needs. If a company said to me they needed to rewire a sites wiring using their "standardized" colours, I would show them the door. Having a standardised colour for function might be convenient when fitting a system from scratch but when adding new zones or replacing detectors etc... it will have minimal impact on time. Also having no standardisation is to some degree security by obscurity.
 
I've just had to fiddle around with another burglar alarm, and wondered what all those colours in the detector cables mean. There's so many different colours that start with yellow, blue, black and red in 4 core. It then gets even prettier with more colours in higher cored cable. I've never read /seen anything about that, so..
  1. Is there a standard colour code for alarm wiring, or is it made up on site?
  2. Wouldn't it be more tamper resistant if the colour scheme was random at each site

Answer to that ....
Don't fiddle
 
Might it then be cheaper /quicker to install a standardised system then? Surely the effort of tracking the wire arrangement for each site is troublesome? If a fitter has 20 clients, it must be a pain to keep records of each installation and leads to mistakes. I'm only imagining what would happen if the mains electricity came through randomly coloured wires, or car wiring to a lesser extent.

If it saved 10% of a fitter's on site time, might that not be justification enough to standardise? Surely the finance director would push for standardisation as in other sectors?
Are you an alarm engineer? Finance director, I know he isn't. Finance director, what has he got to do with anything on the engineering side?

Never kept a record of the colours used for whatever, there's no need. If an engineer has a problem understanding, he's in the wrong job.
 
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