Two PIR sensors to actuate one device

Hi. I'm pretty sure that what I want to do is fine, but might someone with know ledge/experience of such matters please help by confirming? I want to rig up an outdoor device actuated by PIR sensors. There will only be one device, but I'd like to have it respond to either of two sensors, t o get broad area coverage. Is it as simple as wiring both sensor power outp uts to the supply terminals of the device? Clearly, the device will only dr aw the power that it wants to draw, regardless of whether one, other, or bo th PIRs are activated. However, I'm not 100% sure whether standard outdoor PIRs (e.g. from Toolstation) might be designed such that the output termina ls becoming live in the absence of PIR sensor activation would be a proble m. This circumstance would occur if only one PIR is activated, since both o utputs would be connected via the supply terminals on the device.
Cheers. Terry.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 09/09/2015 08:42, snipped-for-privacy@gmail.com wrote:

You can parallel as many pirs as you like provided they are of the relay type which most are. The toolstation ones I bought had relays.
The ones with solid state switches will also work if you can wire a manual override switch to them as they can take mains on the output as provided by the manual override switch.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
dennis@home wrote:

Virtually all have relays in now as it removes any issues with triacs not liking certain types of load.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi. Thanks for all the replies. Yes, the PIRs will be fed from the same circuit. The plan is to wire a phot osensor trigger, whose output goes live in darkness, to a relay, such that I get a "on" switch in daylight only. The two PIRs will both be supplied by the same output of that relay so that they are active in daylight only (wh ich is what I need). Both PIR outputs will be connected to the same power t erminals of the single device that I intend to have them control, which, in turn, ought to keep herons away from my pond! Lol.
Cheers. Terry.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 11/09/2015 15:38, snipped-for-privacy@gmail.com wrote:

The toolstation PIRs have built in photocells. They only operate in the dark once you set the brightness knob to low.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hi. I'm pretty sure that what I want to do is fine, but might someone with knowledge/experience of such matters please help by confirming? I want to rig up an outdoor device actuated by PIR sensors. There will only be one device, but I'd like to have it respond to either of two sensors, to get broad area coverage. Is it as simple as wiring both sensor power outputs to the supply terminals of the device? Clearly, the device will only draw the power that it wants to draw, regardless of whether one, other, or both PIRs are activated. However, I'm not 100% sure whether standard outdoor PIRs (e.g. from Toolstation) might be designed such that the output terminals becoming live in the absence of PIR sensor activation would be a problem. This circumstance would occur if only one PIR is activated, since both outputs would be connected via the supply terminals on the device.
Cheers. Terry.
Are the PIRs powered by a common source?
ie are they fed from the same circuit
--
Adam


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

No, one is fed from his house, the other from a battery, and the other from the streetlights circuit he hotwired into. WTF?
--
A waiter brings the customer the steak he ordered with his thumb over the meat.
"Are you crazy?" yelled the customer, "with your hand on my steak?"
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


That is different "supply" not "circuit".
--
Adam


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

A different circuit wouldn't matter. Same voltage, same phase, etc.
--
Why do MPs drive Volvos?
Because they have safe seats.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


But you know exactly why they should not be off different circuits.
--
Adam


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I cannot think of a reason. The only thing I can think of that you may be getting at is it would bypass a blown breaker if both sensors switched on at once. But then the other breaker would just break on the same fault.
--
A weekend wasted is not a wasted weekend.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


That's why you are completely unemployable.

That's why you are completely unemployable.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 09/09/2015 21:56, Tough Guy no. 1265 wrote:

A different circuit *would* matter. Think about it.
--
Cheers,

John.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 11/09/2015 12:44, John Rumm wrote:

Only if they have the latest protection. I assumed they would be on the same circuit but you are probably correct in saying so.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I have, and there is no reason. The voltage and phase from it is identical.
--
Those who jump off a bridge in Paris are in Seine.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 12/09/2015 15:06, Tough Guy no. 1265 wrote:

Try again, voltage or phase are not the issues.
--
Cheers,

John.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I won't try again, because there is no other reason.
--
What does a Polish woman do after she sucks a cock?
Spits out the feathers.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote: >>>>> A different circuit wouldn't matter. Same voltage, same phase, etc.

Dennis and John have both given different reasons.
Both are viable reasons.
--
Adam


Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Nobody gave any reason, all I've seen is "It would matter".
--
Thought for the Day:
The Bible teaches us to love your neighbour, and the Kama Sutra explains how.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

The trouble with RCDs is they aren't intelligent. And they stop you taking nice shortcuts like using an earth as a neutral. Or grabbing a neutral that happens to be nearby on another circuit when you're in a cramped space in the attic and can't be bothered finding the right one.
--
What lives in the sea, and goes dah di dah dit, dah dah dit dah?
A morse cod.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.