Two PIR sensors to actuate one device
 

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.

Two PIR sensors to actuate one device
 

On 09/09/2015 08:42, wrote:
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.


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.

Two PIR sensors to actuate one device
 

dennis@home wrote:
On 09/09/2015 08:42, wrote:
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.


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.
Virtually all have relays in now as it removes any issues with triacs
not liking certain types of load.

Two PIR sensors to actuate one device
 

wrote in message
...
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

Two PIR sensors to actuate one device
 

On Wed, 09 Sep 2015 13:31:49 +0100, Bob Minchin wrote:

dennis@home wrote:
On 09/09/2015 08:42, wrote:
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.


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.
Virtually all have relays in now as it removes any issues with triacs
not liking certain types of load.

Triacs are ****ing useless. You can't use LEDs or anything under three CFLs.

--
For men, the conversation happens in addition to driving
whereas for women the driving is something that happens in addition to the conversation.

Two PIR sensors to actuate one device
 

On Wed, 09 Sep 2015 19:34:28 +0100, ARW wrote:

wrote in message
...
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

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?"
"What" answers the waiter, "You want it to fall on the floor again?"

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW
wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?


That is different "supply" not "circuit".

--
Adam

Two PIR sensors to actuate one device
 

On Wed, 09 Sep 2015 21:46:55 +0100, ARW wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW
wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

--
Why do MPs drive Volvos?
Because they have safe seats.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.


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

--
Adam

Two PIR sensors to actuate one device
 

On Thu, 10 Sep 2015 19:00:40 +0100, ARW wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

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

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.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Thu, 10 Sep 2015 19:00:40 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

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

I cannot think of a reason.

That's why you are completely unemployable.

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.

That's why you are completely unemployable.

Two PIR sensors to actuate one device
 

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW
wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Two PIR sensors to actuate one device
 

On 09/09/2015 08:42, wrote:

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?

Yup you can do:

http://wiki.diyfaq.org.uk/index.php?...ng_ with_PIRs

With most PIRs and have no problem.

Make sure they are all fed form the same circuit though.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Two PIR sensors to actuate one device
 

On 11/09/2015 12:44, John Rumm wrote:


A different circuit *would* matter. Think about it.



Only if they have the latest protection.
I assumed they would be on the same circuit but you are probably correct
in saying so.

Two PIR sensors to actuate one device
 

En el artículo , John
Rumm escribió:

A different circuit *would* matter. Think about it.

You're assuming PHucker has the ability to think.

--
(\_/)
(='.'=) Bunny says: Windows 10? Nein danke!
(")_(")

Two PIR sensors to actuate one device
 

Hi.
Thanks for all the replies.
Yes, the PIRs will be fed from the same circuit. The plan is to wire a photosensor 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 (which is what I need). Both PIR outputs will be connected to the same power terminals 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.

Two PIR sensors to actuate one device
 

On 11/09/2015 15:38, wrote:
Hi. Thanks for all the replies. Yes, the PIRs will be fed from the
same circuit. The plan is to wire a photosensor 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 (which is what
I need). Both PIR outputs will be connected to the same power
terminals 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.


The toolstation PIRs have built in photocells.
They only operate in the dark once you set the brightness knob to low.

Two PIR sensors to actuate one device
 

On 11/09/2015 13:12, dennis@home wrote:
On 11/09/2015 12:44, John Rumm wrote:


A different circuit *would* matter. Think about it.



Only if they have the latest protection.

You allude to another complication (i.e. a supply from two independent
RCDs would be likely to nuisance trip them). I was thinking more in
terms of basic safety and the ability to isolate a circuit at one point
without risk of it being energised from more than one place).

Still we all know that PHucker is "hard" and immune to electric shock,
so perhaps he should try ;-)

I assumed they would be on the same circuit but you are probably correct
in saying so.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Two PIR sensors to actuate one device
 

En el artículo , John
Rumm escribió:

Still we all know that PHucker is "hard" and immune to electric shock,
so perhaps he should try ;-)

Assuming he practices what he preaches, I feel very sorry for the next
occupier of his house. They're in for some DIY nasties.

--
(\_/)
(='.'=) Bunny says: Windows 10? Nein danke!
(")_(")

Two PIR sensors to actuate one device
 

On Fri, 11 Sep 2015 12:44:06 +0100, John Rumm wrote:

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW
wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

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.

Two PIR sensors to actuate one device
 

On 12/09/2015 15:06, Tough Guy no. 1265 wrote:
On Fri, 11 Sep 2015 12:44:06 +0100, John Rumm
wrote:

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW

wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Two PIR sensors to actuate one device
 

"John Rumm" wrote in message
o.uk...
On 11/09/2015 13:12, dennis@home wrote:
On 11/09/2015 12:44, John Rumm wrote:


A different circuit *would* matter. Think about it.



Only if they have the latest protection.

You allude to another complication (i.e. a supply from two independent
RCDs would be likely to nuisance trip them). I was thinking more in terms
of basic safety and the ability to isolate a circuit at one point without
risk of it being energised from more than one place).

Still we all know that PHucker is "hard" and immune to electric shock, so
perhaps he should try ;-)

I assumed they would be on the same circuit but you are probably correct
in saying so.

I had both the isolation and the dual RCD CU in mind when I posted my reply.

The isolation was the obvious (and the most dangerous scenario).

The dual RCD and two PIRs was something that I came across at work a few
weeks ago when fault finding after fitting a new CU. The installation passed
the test before the CU was fitted as the switched live from the second PIR
was open circuit because it was daylight when the test was done.

The first rule of RCD fault finding is not to barge in there with a megger
but to talk to the customer and try and work out if there is something
specific about the the RCD tripping (certain times, use of items. the
weather etc).

This customer blamed the cat going out at night.


--
Adam

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm wrote:

On 12/09/2015 15:06, Tough Guy no. 1265 wrote:
On Fri, 11 Sep 2015 12:44:06 +0100, John Rumm
wrote:

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW

wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

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.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.


Dennis and John have both given different reasons.

Both are viable reasons.

--
Adam

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 17:11:19 +0100, ARW wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

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.

Two PIR sensors to actuate one device
 

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Two PIR sensors to actuate one device
 

On 12/09/2015 17:16, Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason, all I've seen is "It would matter".

OK, subtitles for the hard of thinking:

1) If you combine the switched live connections of two circuits powered
via different RCDs, then you will get a RCD trip on one or both devices
the moment the light comes on.

2) By cross wiring a circuit from two MCBs you have now made it
implicitly dangerous to maintain - since even if you isolate the circuit
you are working on, it can still be back fed from another. This is
similar to the problem you encounter with borrowed neutrals only worse.

3) If the circuits are protected with MCBs (especially if rated for
different trip currents or curves), you may end up implicitly removing
basic fault protection entirely from one or both circuits, thus creating
both fire and electrocution risks.

4) You may also end up removing overload protection.

However on the plus side, you would highlight that the electrical system
has been interfered with by a clueless and dangerous ****, and hence
everything should be treated with suspicion!


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

--
Why are Jewish Men circumcised? Because Jewish women don't like anything that isn't 20% off.

Two PIR sensors to actuate one device
 

In article ,
Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

an answer was posted about an hour before you wrote your comment. if you
couldn't work out the answer supplied, you shouldn't be playing with
electricity.

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 19:04:25 +0100, John Rumm wrote:

On 12/09/2015 17:16, Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason, all I've seen is "It would matter".

OK, subtitles for the hard of thinking:

1) If you combine the switched live connections of two circuits powered
via different RCDs, then you will get a RCD trip on one or both devices
the moment the light comes on.

A good reason to use fuses instead of those annoying things. Or one RCD for the whole house like they used to. I will never put RCDs in my fusebox, they're a ****ing nuisance.

2) By cross wiring a circuit from two MCBs you have now made it
implicitly dangerous to maintain - since even if you isolate the circuit
you are working on, it can still be back fed from another. This is
similar to the problem you encounter with borrowed neutrals only worse.

You switch one off, you test it, find it's still live, and switch the other off. The chances of it becoming live while you're working on it are negligible.

3) If the circuits are protected with MCBs (especially if rated for
different trip currents or curves), you may end up implicitly removing
basic fault protection entirely from one or both circuits, thus creating
both fire and electrocution risks.

Pansy.

4) You may also end up removing overload protection.

However on the plus side, you would highlight that the electrical system
has been interfered with by a clueless and dangerous ****, and hence
everything should be treated with suspicion!

Or wired by someone who isn't such a pessimistic pussy as you.

--
What lives in the sea, and goes dah di dah dit, dah dah dit dah?
A morse cod.

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 19:04:25 +0100, John Rumm wrote:

On 12/09/2015 17:16, Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason, all I've seen is "It would matter".

OK, subtitles for the hard of thinking:

1) If you combine the switched live connections of two circuits powered
via different RCDs, then you will get a RCD trip on one or both devices
the moment the light comes on.

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.

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 20:16:51 +0100, Charles Hope wrote:

In article ,
Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

an answer was posted about an hour before you wrote your comment.

In another subthread. Like I'm going to read all of them before replying to the first one.

if you
couldn't work out the answer supplied, you shouldn't be playing with
electricity.

Electricity isn't dangerous you pathetic little girl.

--
Murphy says to Paddy, "What ya talkin into an envelope for?" "I'm sending a voicemail ya thick sod!"

Two PIR sensors to actuate one device
 

On Sat, 12 Sep 2015 20:16:51 +0100, Charles Hope wrote:

In article ,
Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

an answer was posted about an hour before you wrote your comment. if you
couldn't work out the answer supplied, you shouldn't be playing with
electricity.

It's my house, I'll have it as dangerous as I like.

--
Murphy says to Paddy, "What ya talkin into an envelope for?" "I'm sending a voicemail ya thick sod!"

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Fri, 11 Sep 2015 12:44:06 +0100, John Rumm
wrote:

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW

wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have,

But don't have anything viable to think with.

and there is no reason.

There are a number of reasons.

The voltage and phase from it is identical.

Pity that there is more involved than just voltage and phase.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

On 12/09/2015 15:06, Tough Guy no. 1265 wrote:
On Fri, 11 Sep 2015 12:44:06 +0100, John Rumm
wrote:

On 09/09/2015 21:56, Tough Guy no. 1265 wrote:
On Wed, 09 Sep 2015 21:46:55 +0100, ARW

wrote:

"Tough Guy no. 1265" wrote in message
...
On Wed, 09 Sep 2015 19:34:28 +0100, ARW

wrote:

wrote in message
...
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

No, one is fed from his house, the other from a battery, and the
other
from the streetlights circuit he hotwired into. WTF?

That is different "supply" not "circuit".

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Thanks for that completely superfluous proof
of why you are completely unemployable and
keep getting the bums rush from any place
actually stupid enough to employ you.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase, etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason,

Another lie.

all I've seen is "It would matter".

Then you need new glasses, BAD.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts
wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

Another lie. They did it a bit cryptically
initially, but have spelt it out in full now.

It will be interesting to see if you have the
balls to admit to your terminal stupidity.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 19:04:25 +0100, John Rumm
wrote:

On 12/09/2015 17:16, Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase,
etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason, all I've seen is "It would matter".

OK, subtitles for the hard of thinking:

1) If you combine the switched live connections of two circuits powered
via different RCDs, then you will get a RCD trip on one or both devices
the moment the light comes on.

A good reason to use fuses instead of those annoying things.

Irrelevant to your terminal stupidity.

Or one RCD for the whole house like they used to.

They don't anymore, stupid.

I will never put RCDs in my fusebox, they're a ****ing nuisance.

Irrelevant to your terminal stupidity.

2) By cross wiring a circuit from two MCBs you have now made it
implicitly dangerous to maintain - since even if you isolate the circuit
you are working on, it can still be back fed from another. This is
similar to the problem you encounter with borrowed neutrals only worse.

You switch one off, you test it, find it's still live,

That isn't necessarily going to happen with a PIR, stupid.

and switch the other off. The chances of it becoming live while you're
working on it are negligible.

Thanks for that completely superfluous proof of why you
are completely unemployable and keep getting the bums
rush when any operation is actually stupid enough to
employ you until it becomes obvious to them what there
is between your ears, just dog ****.

3) If the circuits are protected with MCBs (especially if rated for
different trip currents or curves), you may end up implicitly removing
basic fault protection entirely from one or both circuits, thus creating
both fire and electrocution risks.

Pansy.

Thanks for that completely superfluous proof of why you
are completely unemployable and keep getting the bums
rush when any operation is actually stupid enough to
employ you until it becomes obvious to them what there
is between your ears, just dog ****.

4) You may also end up removing overload protection.

However on the plus side, you would highlight that the electrical system
has been interfered with by a clueless and dangerous ****, and hence
everything should be treated with suspicion!

Or wired by someone who isn't such a pessimistic pussy as you.

Thanks for that completely superfluous proof of why you
are completely unemployable and keep getting the bums
rush when any operation is actually stupid enough to
employ you until it becomes obvious to them what there
is between your ears, just dog ****.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 19:04:25 +0100, John Rumm
wrote:

On 12/09/2015 17:16, Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 17:11:19 +0100, ARW
wrote:

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 16:54:51 +0100, John Rumm
wrote:

A different circuit wouldn't matter. Same voltage, same phase,
etc.

A different circuit *would* matter. Think about it.

I have, and there is no reason. The voltage and phase from it is
identical.

Try again, voltage or phase are not the issues.

I won't try again, because there is no other reason.

Dennis and John have both given different reasons.

Both are viable reasons.

Nobody gave any reason, all I've seen is "It would matter".

OK, subtitles for the hard of thinking:

1) If you combine the switched live connections of two circuits powered
via different RCDs, then you will get a RCD trip on one or both devices
the moment the light comes on.

The trouble with RCDs is they aren't intelligent.

But they are more useful than no RCD in plenty of situations.

And they stop you taking nice shortcuts like using an earth as a neutral.

Only completely unemployable fools like you are that stupid.

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.

Thanks for that completely superfluous proof of why you
are completely unemployable and keep getting the bums
rush when any operation is actually stupid enough to
employ you until it becomes obvious to them what there
is between your ears, just dog ****.

Two PIR sensors to actuate one device
 

"Tough Guy no. 1265" wrote in message
...
On Sat, 12 Sep 2015 20:16:51 +0100, Charles Hope
wrote:

In article ,
Tough Guy no. 1265 wrote:
On Sat, 12 Sep 2015 18:07:06 +0100, Tim Watts
wrote:

On 12/09/15 16:59, Tough Guy no. 1265 wrote:

I won't try again,

Ah - the moron's defence...

Those smart alecs who claim to have an answer haven't produced it yet.

an answer was posted about an hour before you wrote your comment. if you
couldn't work out the answer supplied, you shouldn't be playing with
electricity.

It's my house, I'll have it as dangerous as I like.

Thanks for that completely superfluous proof of why you
are completely unemployable and keep getting the bums
rush when any operation is actually stupid enough to
employ you until it becomes obvious to them what there
is between your ears, just dog ****.