P.I.R's

jjrenolds · Posted: Wed Apr 11, 2007 9:43 am Post Subject: P.I.R's

I want to switch one security light from two different places using PIR's. Is there a product to do this or do i have to get 2 off PIR's and wire them into a light? If this is the case is there a standard wiring solution for this practise?

bernardgreen · Posted: Wed Apr 11, 2007 12:31 pm Post Subject:

The PIRs will have a live, switched live ( to the lamp ) and a neutral.

Wire the two PIRs in parallel to the supply. Live to Live and to live supply, Neutral to Neutral and neutral supply.

Wire the two switched lives in parallel and connect the lamp between switched live and neutral.

Connect earths where needed.

jjrenolds · Posted: Wed Apr 11, 2007 2:23 pm Post Subject:

Thanks for that. I am assuming that wiring it in parrallel means the switch rating stays the same. i.e. if i purchase a pir that can switch 500 watts, then doubling up means i just need 2 pirs that can both switch 500 watts?

Steve · Posted: Wed Apr 11, 2007 8:41 pm Post Subject:

jjrenolds wrote:

Thanks for that. I am assuming that wiring it in parrallel means the switch rating stays the same. i.e. if i purchase a pir that can switch 500 watts, then doubling up means i just need 2 pirs that can both switch 500 watts?

If they are both switched on, theoretically the circuit could take 1000w, but that wouldnt happen often so you'd burn the contacts out in them.

If you have 2 500w PIRs, the circuit shouldnt have more than 500w of lighting.

Using contactors or relays means you can switch an infinite load.

Taylortwocities · Posted: Wed Apr 11, 2007 10:38 pm Post Subject:

Crafty wrote:

lighting.

Using contactors or relays means you can switch an infinite load.

Absolutely no limit then? Time to fire up another power station...

TTC

jjrenolds · Posted: Thu Apr 12, 2007 6:10 am Post Subject: thanks

Cheers for that, it hadn't occured to me to use a relay, what a great idea.

I'm done on this one then, thanks for your help

neilsumner · Posted: Thu Apr 12, 2007 12:07 pm Post Subject:

I thought most PIRs that control lighting used relays anyway or do they now use Triacs?

-Neil

Steve · Posted: Thu Apr 12, 2007 5:55 pm Post Subject:

neilsumner wrote:

I thought most PIRs that control lighting used relays anyway or do they now use Triacs?

-Neil

They use weedy contacts that can only just handle the rating specified.

Adam_151 · Posted: Thu Apr 12, 2007 6:02 pm Post Subject:

I'd try and maske sure the PIR's you used were contactor based anyway (just listen for the 'clunk' sound as they pull in!), triac ones might not react too happily being connected in parralell

If they were traic based I'd advise you to consult the maker before using them anyway.

Strictly speaking, you probably should consult the maker anyway as to the suitability of their products to be connected in this way, but as long as you used contactor based devices, I cannot see that it would present any issues

securespark · Posted: Thu Apr 12, 2007 6:12 pm Post Subject:

Crafty wrote:

neilsumner wrote:

I thought most PIRs that control lighting used relays anyway or do they now use Triacs?

-Neil

They use weedy contacts that can only just handle the rating specified.

Crafty likes to hear a satisfying, echoing "CLUNK" as his relays kick in...

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Steve · Posted: Thu Apr 12, 2007 7:33 pm Post Subject:

nothing like it.

ricicle · Posted: Thu Apr 12, 2007 7:44 pm Post Subject:

When I get round to it I'll post a piccy of some 800A contactors we have in our factory

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viney

RACALITE TEST PROCEDURE
WARNING
Mains voltages exist under controller cover. Do not connect or dis-connect any wiring while
mains power is still applied.
EQUIPMENT REQUIRED: High sensitivity (e.g. 20k Ohm/V) multimeter.
FUNCTIONAL TESTS
1. Switch controller to “automatic” operation ad slide switch to “walk test” position;
observe lights (load). Wait at least 1 minute for system to settle.
If the lights activate when no movement is present in front of the heads; Go to 3.
Activate each head in turn. If not all heads active; Go to 4.
2. Remove mains power. Disconnect the “daylight sense” wire from the controller.
Switch to “automatic” and “1” minute. Apply mains power and allow the system to
settle down. Trigger the system once. Measure the time that the lights are on - this
should be approximately 1 minute. Repeat for “5” and “10” minutes. If times are
wrong; Go to 3. Remove mains power. Reconnect daylight sense. Switch to “1”
minute, apply mains power, allow system to settle (wait at least 1 minute) check that
daylight disable operates and system cannot be triggered during daylight.
NOTE: In mult-head system the daylight sense terminal from only 1 head should be
connected to the controller. Choose the head which is in the brightest location.
VOLTAGE TESTS
3. Switch controller to “automatic” operation and slide switch to 1 minute. Measure the voltages between the following points:-Terminals
L&N 240 Vac (120 Vac on RLCIA)
All voltages are positive and measured with respect to “12V Power - “
“12V power +” 11.5 - 12.5 V
“Trigger” - untriggered 8.5 - 11.0 V
- triggered 0 - 1.5 V
“Daylight sense” - day 8.5 - 11.5 V
- night 0 - 1.5 V
* This voltage is only present momentarily while there is movement in front of the head

Taylortwocities · Posted: Sat Oct 11, 2008 8:09 am Post Subject:

What's that all about then, Viney. Just tagged on to an only thread?

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TTC

When you get to the end of your rope, tie a knot and hang on. - F.D.R.