burglar alarm door contacts

[r.b]

Is it true at door contacts you have positive and negative together in one terminal.Also both tamper wires together in another terminal for it to work?

 

[betty swollocks]

Are we talking about magnetic contacts?

Surely if you connect 12v+ and 0v- in the same terminal it would pop the glass fuse on the pcb?

Think of cutting straight through an alarm cable, dead short, blows fuse

What you described is no different

Magnetic door connectors only require no/nc connections as the magnet makes the switch on contact

 

[r.b]

so you only need 2 cores to a door contact no,nc? A take it these are alarm cores?

 

[col]

You've prob seen red/black twisted together in the same terminal. This isn't +ve & -ve though,

I wouldn't go by the colours for either 12v or 230v, black is often switched live so stick a meter on them first.

 

[alpha spark]

U only need an alarm pair but good practice to use tamper pair too but not required u don't need a power pair

I'm no expert in alarms only ever use texecom other members on here will know much more what panel u using

 

[sellers]

2 pairs needed, no power.

Connect your tampers together in there, that way if the cable is cut anywhere it will sound even when unset.

 

[SLIPSHOD & SLAPDASH]

A standard system only uses 2 cores, connected in a closed loop. You also should wire a tamper circuit which is another 2 cores & its those you have seen twisted together in one terminal. The system will work without a tamper circuit if its been linked out at the panel. Detectors also have a cable pair for the 12v feed.

Then you get the more sophisticated systems. I used to use the castle care panels which ran ID chips in each detector. These only needed 2 cores (+ the 12v feed) and connectedacrosss the tamper & detection contacts.. Each ID chip is different so the panel knows what is what

You also have panels which use a FSL (fully supervised loop) This system also uses one pair of cables and 2 resistors to enable both tamper & detection on one loop. This is getting more common and all Class 2 systems have to run it.

Core colours mean nothing. Under the older NACOSS rules you were meant to change colour codes every 10 zones, even on the same system. Different engineers on the same companies use their own colour codes.

 

[r.b]

The door contacts I have are 5 terminals the 2 outer terminals have solder wires coming off them the 3 centre ones are seperate.Where do I put the alarm closed loop 2 wires one core in one end one core in opposite end I know its normally closed just dont know where to put it honestly?

 

[Evans Electric]

The ones with the wires will be the terminals to use . Those wires go to the reed switch in th glass tube . The others are just terminals for looping .

If you're no sure put your meter across the terms and hold the magnet by it to see if it opens .