I put a drill through the wall into the garage yesterday and hit a flex
that had been buried in the garage ceiling and which ran between the
security light and the PIR that feeds it. The fuse on the fused spur
that feeds the PIR didn't blow and I didn't realise what had happened
until I went into the garage, tried to prise some 'silicone' out of the
way with a screwdriver and got a bit of a tingle. The 'silicone' was the
chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

And what would be an acceptable repair? One of the damaged ends is very
short and there's no slack to pull through.

--
F

F wrote:
I put a drill through the wall into the garage yesterday and hit a
flex that had been buried in the garage ceiling and which ran between
the security light and the PIR that feeds it. The fuse on the fused
spur that feeds the PIR didn't blow and I didn't realise what had
happened until I went into the garage, tried to prise some 'silicone'
out of the way with a screwdriver and got a bit of a tingle. The
'silicone' was the chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

The PIR has a permanent live!

And what would be an acceptable repair? One of the damaged ends is
very short and there's no slack to pull through.

Crimps/replace cable?

--
Adam

On 05/08/2012 12:29 ARWadsworth wrote:

F wrote:
I put a drill through the wall into the garage yesterday and hit a
flex that had been buried in the garage ceiling and which ran between
the security light and the PIR that feeds it. The fuse on the fused
spur that feeds the PIR didn't blow and I didn't realise what had
happened until I went into the garage, tried to prise some 'silicone'
out of the way with a screwdriver and got a bit of a tingle. The
'silicone' was the chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

The PIR has a permanent live!

So only the neutral's switched?

And what would be an acceptable repair? One of the damaged ends is
very short and there's no slack to pull through.

Crimps/replace cable?

The (existing) cable was routed through/under a new roof and I can't get
at that routing so it looks as though I'll have to crimp. Unless a
connector strip and insulation tape, then push the repair into the void
above the ceiling, is good enough?

--
F

F wrote:


The (existing) cable was routed through/under a new roof and I can't get
at that routing so it looks as though I'll have to crimp. Unless a
connector strip and insulation tape, then push the repair into the void
above the ceiling, is good enough?


yes: BTTGTTS


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

On 05/08/2012 17:04, F wrote:
On 05/08/2012 12:29 ARWadsworth wrote:

F wrote:
I put a drill through the wall into the garage yesterday and hit a
flex that had been buried in the garage ceiling and which ran between
the security light and the PIR that feeds it. The fuse on the fused
spur that feeds the PIR didn't blow and I didn't realise what had
happened until I went into the garage, tried to prise some 'silicone'
out of the way with a screwdriver and got a bit of a tingle. The
'silicone' was the chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

The PIR has a permanent live!

So only the neutral's switched?

No, the PIRs have three connections; perm live, switch live and neutral.

The dangerous bodge used on some of these installations uses three core
flex, and repurposes the earth wire as something else (something you are
not supposed to do to a earth/CPC even if you sleeve the wire)

(three core and earth cable would be the appropriate choice)

And what would be an acceptable repair? One of the damaged ends is
very short and there's no slack to pull through.

Crimps/replace cable?

The (existing) cable was routed through/under a new roof and I can't get
at that routing so it looks as though I'll have to crimp. Unless a
connector strip and insulation tape, then push the repair into the void
above the ceiling, is good enough?

As long as the repair is either enclosed in heatshrink or in small
plastic box like a chockbox etc.

--
Cheers,

John.

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

On 05/08/2012 22:21 John Rumm wrote:

On 05/08/2012 17:04, F wrote:
On 05/08/2012 12:29 ARWadsworth wrote:

F wrote:
I put a drill through the wall into the garage yesterday and hit a
flex that had been buried in the garage ceiling and which ran between
the security light and the PIR that feeds it. The fuse on the fused
spur that feeds the PIR didn't blow and I didn't realise what had
happened until I went into the garage, tried to prise some 'silicone'
out of the way with a screwdriver and got a bit of a tingle. The
'silicone' was the chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

The PIR has a permanent live!

So only the neutral's switched?

No, the PIRs have three connections; perm live, switch live and neutral.

The dangerous bodge used on some of these installations uses three core
flex, and repurposes the earth wire as something else (something you are
not supposed to do to a earth/CPC even if you sleeve the wire)

(three core and earth cable would be the appropriate choice)

I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.

--
F

"F" news@nowhere wrote in message
news
I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to the
one between the fused spur and the PIR. I would have expected the live in
question to be 'off' as it was daylight and the PIR wouldn't have switched
it to 'on'.

It depends on where the live is feed from.

If the live feed from the CU goes to the PIR first there may only be
switched live and neutral to the lamp.

However if as on one of mine the feed goes to the lamp first there will be
permanent live, switched live and neutral in the cable.
Quite common when a PIR is added to an existing lamp.

There is probably an earth too, but it can be missing.

On 06/08/2012 07:52 dennis@home wrote:



"F" news@nowhere wrote in message
news
I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.

It depends on where the live is feed from.

If the live feed from the CU goes to the PIR first there may only be
switched live and neutral to the lamp.

However if as on one of mine the feed goes to the lamp first there will
be permanent live, switched live and neutral in the cable.
Quite common when a PIR is added to an existing lamp.

There is probably an earth too, but it can be missing.

It's CU ring fused spur PIR lamp. From the fused spur onwards
it's all in 3-core (live, neutral, earth) flex. The PIR is this one:
http://www.toolstation.com/shop/Ligh.../sd3296/p19615

--
F

"F" news@nowhere wrote in message
o.uk...
On 06/08/2012 07:52 dennis@home wrote:



"F" news@nowhere wrote in message
news
I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.

It depends on where the live is feed from.

If the live feed from the CU goes to the PIR first there may only be
switched live and neutral to the lamp.

However if as on one of mine the feed goes to the lamp first there will
be permanent live, switched live and neutral in the cable.
Quite common when a PIR is added to an existing lamp.

There is probably an earth too, but it can be missing.

It's CU ring fused spur PIR lamp. From the fused spur onwards it's
all in 3-core (live, neutral, earth) flex. The PIR is this one:
http://www.toolstation.com/shop/Ligh.../sd3296/p19615

Check the live and neutral aren't swapped on the PIR output then.

On 2012-08-05, F wrote:

On 05/08/2012 22:21 John Rumm wrote:

No, the PIRs have three connections; perm live, switch live and neutral.

The dangerous bodge used on some of these installations uses three core
flex, and repurposes the earth wire as something else (something you are
not supposed to do to a earth/CPC even if you sleeve the wire)

(three core and earth cable would be the appropriate choice)

I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.


Think about it like "loop-in" ceiling light wiring: there's an
always-on live running from the light fitting to the wall switch (or
PIR), and a switched live running back from the switch (or PIR) to the
light fitting.


John & Adam: Do all PIRs need a neutral as well as live coming in &
switched live going back? I think I've seen two-connection ones (not
counting the earth) in the past, although I could be wrong.

On 05/08/2012 11:10, F wrote:
I put a drill through the wall into the garage yesterday and hit a flex
that had been buried in the garage ceiling and which ran between the
security light and the PIR that feeds it. The fuse on the fused spur
that feeds the PIR didn't blow and I didn't realise what had happened
until I went into the garage, tried to prise some 'silicone' out of the
way with a screwdriver and got a bit of a tingle. The 'silicone' was the
chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

And what would be an acceptable repair? One of the damaged ends is very
short and there's no slack to pull through.


Further on, you say the connection is SUPPLY---- PIR ------- Lamp

You have drilled into the cable between the PIR and the lamp.

The PIR may not have a neutral connection, it may rely on leaking a
small current through the lamp to power the PIR electronics, if this is
the case, you could then get a tingle from this leakage current, if it
says it is not suable for fluorescent/low energy lamps, then this is
almost certainly the case)

If the PIR is drawing under 30mA then it probably wouldn't trip and RCD
either.

Repair in order of preference

1. Replace the cable if practical
2. Replace the easiest to replace section, joining the cable with crimps
if the join is not going to stay accessible
3. insert a short length of cable and make two new connection (crimped
if the joints are got going to stay accessible)

--
Toby...
Remove pants to reply

On 06/08/2012 12:25, Adam Funk wrote:
On 2012-08-05, F wrote:

On 05/08/2012 22:21 John Rumm wrote:

No, the PIRs have three connections; perm live, switch live and neutral.

The dangerous bodge used on some of these installations uses three core
flex, and repurposes the earth wire as something else (something you are
not supposed to do to a earth/CPC even if you sleeve the wire)

(three core and earth cable would be the appropriate choice)

I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.


Think about it like "loop-in" ceiling light wiring: there's an
always-on live running from the light fitting to the wall switch (or
PIR), and a switched live running back from the switch (or PIR) to the
light fitting.


John & Adam: Do all PIRs need a neutral as well as live coming in &
switched live going back? I think I've seen two-connection ones (not
counting the earth) in the past, although I could be wrong.

"All" is a strong word ;-)

Most will require a L&N connection to function. However some designed
for installation in the location of an existing switch may find a
neutral reference by drawing a small amount of current through the lamp
itself. Generally these only work properly with traditional filament lamps.


--
Cheers,

John.

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

On 2012-08-06, John Rumm wrote:

On 06/08/2012 12:25, Adam Funk wrote:

John & Adam: Do all PIRs need a neutral as well as live coming in &
switched live going back? I think I've seen two-connection ones (not
counting the earth) in the past, although I could be wrong.

"All" is a strong word ;-)

Most will require a L&N connection to function. However some designed
for installation in the location of an existing switch may find a
neutral reference by drawing a small amount of current through the lamp
itself. Generally these only work properly with traditional filament lamps.

OK, that's what I've seen then. Thanks.

On 05/08/2012 22:49, F wrote:
On 05/08/2012 22:21 John Rumm wrote:

On 05/08/2012 17:04, F wrote:
On 05/08/2012 12:29 ARWadsworth wrote:

F wrote:
I put a drill through the wall into the garage yesterday and hit a
flex that had been buried in the garage ceiling and which ran between
the security light and the PIR that feeds it. The fuse on the fused
spur that feeds the PIR didn't blow and I didn't realise what had
happened until I went into the garage, tried to prise some 'silicone'
out of the way with a screwdriver and got a bit of a tingle. The
'silicone' was the chewed up white flex.

I'm not sure why I should get a tingle from the flex when the PIR was
'off' due to it being the middle of the day.

Anyone?

The PIR has a permanent live!

So only the neutral's switched?

No, the PIRs have three connections; perm live, switch live and neutral.

The dangerous bodge used on some of these installations uses three core
flex, and repurposes the earth wire as something else (something you are
not supposed to do to a earth/CPC even if you sleeve the wire)

(three core and earth cable would be the appropriate choice)

I'm confused...

The flex I hit was the one between the PIR and the lamp, as opposed to
the one between the fused spur and the PIR. I would have expected the
live in question to be 'off' as it was daylight and the PIR wouldn't
have switched it to 'on'.

It depends on how these things have been wired... If the wiring delivers
power to the PIR first, then it is possible that there is only a
switched supply to to the lamp. In which case you either have one of the
rare PIRs designed to work without a neutral, that are never truly "off"
and pass a small current through the lamp at all times, or, it has been
incorrectly wired with the neutral being switched rather than the live.

Personally I tend to run 3&E between all the parts of PIR switched
systems so that you can add parallel PIRs or override switches anywhere,
and you have some flexibility for future modifications.

--
Cheers,

John.

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

Thanks for all the feedback. I'll check that the connections are correct
and put the repair into a chockbox.

--
F

On 06/08/2012 19:53, F wrote:
Thanks for all the feedback. I'll check that the connections are correct
and put the repair into a chockbox.


Will the joint be accessible later, or will it be covered over, if it is
going to be covered over with plasterboard etc.. you need to crimp it.

--
Toby...
Remove pants to reply