and then go bright when it switches off. The shower is on a fuse of its
own. Should I be suspiciuos of the wiring?

cheers roy

"misterroy" wrote in message
news

and then go bright when it switches off. The shower is on a fuse of its
own. Should I be suspiciuos of the wiring?

cheers roy

It sounds like your incoming supply cable/meter may be undersized, have a
look on the front of the meter , it will have an amp rating, old properties
sometimes have 20 amp meters still and wiring to match. 80 amp is more like
standard now.

thanks all, I'll sleep easy tonight. The house is rural, maybe even very
rural.

cheers roy

"misterroy" wrote in message
news

and then go bright when it switches off. The shower is on a fuse of its
own. Should I be suspiciuos of the wiring?

Are you on a rural overhead supply? If so, the problem is most likely that
the supply to the property is inadequate.

Colin Bignell

On Fri, 26 Mar 2004 07:32:28 -0000, in uk.d-i-y misterroy
strung together this:


and then go bright when it switches off. The shower is on a fuse of its
own. Should I be suspiciuos of the wiring?

I wouldn't worry. Most properties do that, if it does it excessively
then it might be worth checking out the size of supply to the property
but a little dimming of the lights is fairly common.
--

SJW
A.C.S. Ltd.

but a little dimming of the lights is fairly common.

********!

PJ wrote:


but a little dimming of the lights is fairly common.

********!

It's quite trivial to see the effect on the lights that the electric
hot water heater cycling on and off has here.

"Ian Stirling" wrote in message
...
PJ wrote:


but a little dimming of the lights is fairly common.

********!

It's quite trivial to see the effect on the lights that the electric
hot water heater cycling on and off has here.

Maybe, but to say it's fairly common is.... ********.

PJ wrote:

"Ian Stirling" wrote in message
...
PJ wrote:


but a little dimming of the lights is fairly common.

********!

It's quite trivial to see the effect on the lights that the electric
hot water heater cycling on and off has here.

Maybe, but to say it's fairly common is.... ********.

Do you a) have a definition of fairly common, and b) have the results
of a survey?

PJ wrote:

Maybe, but to say it's fairly common is.... ********.

All the ones I have seen (only about 3 in total - so not a statistically
significant sample) seem to cause some dimming - the 10kW+ beasties in
particular cause a quite noticeable effect.

So "fairly common" would seem to be fairly accurate - but maybe not as
common as ********. ;-)

--
Cheers,

John.

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

"PJ" wrote in message ...

Maybe, but to say it's fairly common is.... ********.

There's nothing like a well-argued rational reply, and that _is_ nothing
like a ...

Lurch is quite right. The great majority of domestic electricity supplies
have a source impedance at the supply terminals in the range 15 to 350
milliohms. Impedances at the low end of this range are comparatively rare
(it implies that you are very close to the sub-station and have a short
service cable) and in my experience the most commonly occurring values are
between about 70 and 250 milliohms [1]. If the electric shower draws, say,
40 amps (9.2 kW) then the voltage reduction is most likely to be in the
range 3 to 10 volts [2]. The eye is very sensitive to small step changes in
brightness and with tungsten filament lamps a 3 volt step will be just about
noticeable; a 10 volt step will be very noticeable. In the worst case, with
a 350 milliohm source impedance, the voltage reduction will be 14 volts,
leading to very noticeable dimming.

So, yes, dimming is normal, and common.


[1] AIUI, the situation may be different in London (old LEB area) where the
supply network tends to be denser, with correspondingly higher fault levels
/ lower supply impedances. I have no experience in this area and can't
comment further.

[2] Pedants will no doubt wish to point out that this these figures are
approximations which ignore the fact that part of the supply impedance is
reactive. True, but they are good enough for the present purpose.

--
Andy

"PJ" wrote in message
...
********!
How many?

Well, my lights dim due to the shower also,
but I'll try not to worry too much about it.

On Fri, 26 Mar 2004 21:44:32 GMT, in uk.d-i-y "chuffed_2_bits"
strung together this:


"PJ" wrote in message
...
********!
How many?

Well, my lights dim due to the shower also,

Mine do, they often dim for no apparent reason. It's not dangerous or
anything, just this tinpot 2nd rate half arsed supply isn't in tip top
condition. It is the middle of nowhere.

but I'll try not to worry too much about it.

I don't.
--

SJW
A.C.S. Ltd.

(Lurch) wrote in message ...
On Fri, 26 Mar 2004 21:44:32 GMT, in uk.d-i-y "chuffed_2_bits"
strung together this:
"PJ" wrote in message


********!
How many?

Well, my lights dim due to the shower also,

Mine do, they often dim for no apparent reason. It's not dangerous or
anything, just this tinpot 2nd rate half arsed supply isn't in tip top
condition. It is the middle of nowhere.

For rural houses its simply normal. Put a 10kW load online and youre
going to get a bit of Vdrop.

OTOH we dont know how much things are dimming in the OP's case. If the
dimming is considerable then it may be time to get genuinely worried.


Regards, NT

In message ,
chuffed_2_bits writes

"PJ" wrote in message
...
********!
How many?

Well, my lights dim due to the shower also,
but I'll try not to worry too much about it.

My house in Indonesia used to have a 1.1kW supply and the fuse box was
outside the front door. The water pump was old.

I'm sure you can imagine the picture halfway through a shower
--
geoff

On Fri, 26 Mar 2004 16:24:36 +0000, PJ wrote:



but a little dimming of the lights is fairly common.

********!

Same to you.

I.e. IME a slight reduction/increase in a filament bulb can often be
observed when the unit switches on/off the dimming is not such that
anyone could notice otherwise.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html
Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html

misterroy wrote in
news

and then go bright when it switches off. The shower is on a fuse of its
own. Should I be suspiciuos of the wiring?


When my Mum prints something the lamp (plugged into the same socket as the
printer), dims on and off in time to the movement of the carriage head.
It's been like that years and the house it still standing so it must be
safe.

--
john

"Technology is dominated by two types of people: those who understand what
they do not manage, and those who manage what they do not understand." -
Putt's Law