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Jim Thomas Jim Thomas is offline
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Default Two PIR sensors to actuate one device



"Tough Guy no. 1265" wrote in message
news
On Mon, 21 Sep 2015 23:29:34 +0100, Jim Thomas wrote:



"Tough Guy no. 1265" wrote in message
news
On Sat, 19 Sep 2015 04:54:09 +0100, Jim Thomas wrote:



"Tough Guy no. 1265" wrote in message
news On Fri, 18 Sep 2015 00:14:05 +0100, Jim Thomas wrote:



"Tough Guy no. 1265" wrote in message
news On Mon, 14 Sep 2015 21:52:29 +0100, Jim Thomas
wrote:



"Tough Guy no. 1265" wrote in message
news On Mon, 14 Sep 2015 21:26:56 +0100, Jim Thomas
wrote:



"Tough Guy no. 1265" wrote in message
news On Mon, 14 Sep 2015 20:06:41 +0100, John Rumm
wrote:

On 14/09/2015 15:12, Tough Guy no. 1265 wrote:
On Mon, 14 Sep 2015 02:48:48 +0100, John Rumm
wrote:

On 13/09/2015 20:22, Tough Guy no. 1265 wrote:
On Sun, 13 Sep 2015 20:19:43 +0100, dennis@home

wrote:

On 13/09/2015 20:11, Tough Guy no. 1265 wrote:

I'm right, if you think I'm not, prove it. A sensor needs
power
to
activate the relay. It cannot have this until its source
circuit
is
made live, and you switched that off. All the other
sensor
can
do
is
connect live to the output of the relay contact of the
first
sensor.
This will not power up the first sensor so its relay
remains
open.


If you ignore the circuit to the lights and any manual
override
switch.

Only the light in question could become live, nothing else.

And let's say someone wanted to work on the switched live -
adding
an
additional lamp perhaps?

They'd have checked neither PIR was turning the thing on. Why
would
you
assume they were on the same circuit?

So if we apply that logic, before touching anything we need to
check
every light switch, PIR, FCU and anything else with a switch on
it,
on
any circuit, just in case some clueless PHucker decided to wire
it
up
to
the lamp as well.

Does your horse need feeding?

What a stupid train of thought.

We'll see...

Both PIRs activate the outside light you're working on, so you
check
both.
Why would you check the bedroom light switch

Because with fools like you around, anything
is possible with borrowed neutrals etc.

If the device works, it was done correctly.

Not if the fool has borrowed a neutral and
only the most obvious circuit is disabled.

The device works, what more do you want?

One that is done safely so that when it fails,
as it inevitably will sometime, someone who
isn't as careful as Adam won't get killed fixing
it when they have done the most obvious
thing and turned just the circuit that appears
to be connect to it off before fixing it.

Wimp.

Makes no sense to kill someone else.

Their problem for not being careful.


That's the way most european and third
world countries do their electrical systems.


Which is why they do better than us at a lot of things.


Nope, the krauts do better than you lot at almost everything
but don't do their electrical systems like that.

China for example is leading the world economy


Like hell it is.

because "developed" countries waste money on safety.


Nope, because they pay MUCH lower wages than the west does.

Yes, you can certainly turn the entire house off
when doing anything to the electrical system,
but it makes a lot more sense to not use more
than one circuit for a particular light and to not
borrow neutrals.


If you have two lighting circuits, just turn them both off.


You don't know whether some fool like you has
borrowed a neutral from a non lighting circuit.

And think of the time you save borrowing a neutral.


Think of the time you save when dead.

when you know that doesn't activate it,

But don't know what some fool like you has done with borrowed
neutrals
etc.

That's what a multimeter is for.

Not possible to use one when walking past the PIRs.

Why do you think that?

**** all who even have a multimeter have one with
a max min function or even know that can be used for.

What cheap **** meter do you have?!

I have a Fluke 19, but **** all have a meter anything like that.

My 20 year old meter has it ffs.

**** all have a meter that does.

Even if you don't, you can set it to bleep if there's a voltage.

**** all have a meter that does.

They should.


Makes a lot more sense to turn the entire house off instead.


A decent meter is a basic tool, like a screwdriver.


**** all even know how to use a basic multimeter, let alone a
decent one which has max min or even how to use those functions.

Even someone as stupid as you knows how to turn the entire house off.

And borrowed neutrals don't endanger you when working on the
lights.

Wrong.

You test for lives with the multimeter.

That assumes that you know how to use one to do that.

Most of those who work on that sort of thing don't
and don't even have one so it makes a lot more
sense to not allow borrowed neutrals or to use
more than one circuit when you have more than
one PIR controlling the light.

Anyone who knows enough to fix a light has a meter.

Wrong, as always.

They don't cost much nowadays.


Those with a max min function which are
safe to use on the mains aren't that cheap.


All multimeters take mains voltage.


Very dangerously with the worst of them.

And max min is available on all but the very ****tiest ones.


And **** all who can manage to wire a light even know
how to use the max min function in those in that situation.

And it's a lot quicker to just turn the entire house
off and much safer with an intermittent fault too.

and you know there's nobody else in the house to press it?

Irrelevant if some fool like you has done
something stupid with borrowed neutrals etc.

Even turning the entire house off before touching anything
isn't going to protect you with fools like you around who
could have done anything, including steal power.

Then never assume, carry a meter or volt probe with you.

Carrying the meter or volt probe wont get you
anywhere useful when walking past both PIRs.

Why do you believe this?

Because even you should have noticed that you
can't actually see what the voltage at the light is
doing when you walk past the PIR with the meter
or volt probe in your hand.

You sit it so you can see it,

Not even possible with most lights with more than one PIR.


Use a mirror.


Much easier to turn the whole house off
before doing any work on that config.


Which means the borrowed neutral and using the other circuit isn't a
problem.


But can kill those who don't turn the whole house off.

get a decent meter with memory,

**** all have a meter that does.

or ask someone else to watch it,

**** all realise that its possible some fool
like you has used more than one circuit.


**** all are scared of only 240 volts.


Its only fools like you that aren't.


I'm a realist, 240 volts just makes you jump.


Must explain how all those get killed by it.