How To Connect A Pir - With Just 4 Wires?

[kenniewaters]

I am installing a PIR in a remote room using an existing cable.

The cable is only 4 core and really difficult to re-lay.

The PIR is a Pyronix KX15DT.

I could use one pair for power and one for the alarm. And ignore the tamper circuit and live with the risk.

OR...and this is the complicated bit!

The instructions/diagram that come with the PIR show a wiring setup like this:

Two wires to supply power.

And two wires connected as follows:

One wire from the panel Zone to alarm termiinal 1 on the PIR.

An internal resistor from that terminal to alarm terminal 2.

Another internal resistor from alarm terminal 2 to tamper terminal 1.

And then a return wire from tamper terminal 2 to the panel Zone.

There is a set of jumpers on the PIR to allow selection of the two resistor values

Does that make sense?

It seems to suggest that if either the alarm or the tamper is triggered then the zone will alarm.

But that would only happen if the system is armed - I think.

If the tamper is opened when the system is not armed then it won't cause a tamper alarm - or could it?

Apologies if this appears confused!! I am. I just may be mis-reading the diagram.

Ken

[amateurandy]

It's called, I think, EOL wiring and is widely used by professionals in various configurations. It gives better protection if configured properly.

You'll need to provide some details of the panel so that one of the Pro's here can advise if it's feasible, especially as it sounds like you'll be mixing it with a tamper loop.

[lawandorder]

I think you ared describing EOL (end of line) wiring which is where the panel recognises the different resisatnce values in response to the condition of the detector.

This method will only work with some panels.

What panel are you using?

There is a method of using a 4 core for a PIR without EOL and still maintaining the tamper protection with older non EOL panels but without meaning to be disrespectful it is hard to explain in a way that would make much sense to somebody without a pretty advanced knowledge of alarms.

[kenniewaters]

Sorry, the panel is a brand new HKC SW812 unit (maybe sold only in Ireland - maybe badged)

It has 8 zones and lots of other bells and whistles, including a digi-modem.

I believe it can support the various types of EOL wiring.

I am told it is 'state of the art' !!

Each zone has two alarm and two tamper terminals.

The PIR has 6 connection points: Power + and -, Alarm x 2 Tamper x 2

Ken

[hpotter]

I am installing a PIR in a remote room using an existing cable.

The cable is only 4 core and really difficult to re-lay.

The PIR is a Pyronix KX15DT.

I could use one pair for power and one for the alarm. And ignore the tamper circuit and live with the risk.

OR...and this is the complicated bit!

The instructions/diagram that come with the PIR show a wiring setup like this:

Two wires to supply power.

And two wires connected as follows:

One wire from the panel Zone to alarm termiinal 1 on the PIR.

An internal resistor from that terminal to alarm terminal 2.

Another internal resistor from alarm terminal 2 to tamper terminal 1.

And then a return wire from tamper terminal 2 to the panel Zone.

There is a set of jumpers on the PIR to allow selection of the two resistor values

Does that make sense?

It seems to suggest that if either the alarm or the tamper is triggered then the zone will alarm.

But that would only happen if the system is armed - I think.

If the tamper is opened when the system is not armed then it won't cause a tamper alarm - or could it?

Apologies if this appears confused!! I am. I just may be mis-reading the diagram.

Ken

Yer, FSL (fully supervised loop), straight forward enough if panel can cope. I dont know about all panels but modern G2 scantronic can handle it if you make all zones FSL in the programming which means rearranging wiring on all detectors & adding resistors to all zones.

Some older menvier & scannys can aswell but easier if you can post what panel & age you got! (age of panel that is!!!)

oops jumped the gun. Sorry dont know of HKC

[kka]

if it does eol, then all your zone will need to be made the same....

[kenniewaters]

As a last resort I have read the manual (again!!)

It describes "dual end of line wiring"

It seems to be what I want

It shows 4 wires being used to connect a PIR - 2 for power and 2 as described in my original post.

The zone tamper on the panel is unused.

The manual says that any zone can have this 'dual eol' property (i.e. it is configurable on a per zone basis).

So, it would seem that the only downside of this arrangement is that if the alarm is unset, then a tamper attack on the PIR will be undetected.

But if the alarm is armed, then either a PIR alarm or a tamper will be detected.

I will have to do some tests!!

Ken

[Rulland]

On some panels there are four connections for each zone-2 alarm and 2 tamper-if you use EOL with resistors on thoses types of panel then normaly just two connections are made to the zone, but tamper etc is still monitored as the zone is configured as EOL.

As an example if a 4.7k resistor is used for the alarm contact and a 2.2k resistor is used for the tamper/EOL,

In the 'active' condition the panel would see 4.7 plus 2.2 equals roughly 7k ohms.

In the 'settled' condition the panel would just see the 2.2 or EOL.

In the 'tamper' condition the panel would see zilch IE cut cable-open circuit or direct short tamper as well.

[kenniewaters]

AH! That explains it.

Now I understand

Many thanks.

Ken.