I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

This led me to wonder how I could measure
the power consumption of our 2 immersion heaters.
I assume it is dangerous, probably illegal,
to fit a power socket in the bathroom.

Is there any simple way of getting round this?

Timothy Murphy wrote:

Is there any simple way of getting round this?

A few:

1) Look at the ratings plate
2) Clamp meter
3) Using the lekky meter

--
Cheers,

John.

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\================================================= ================/

John Rumm wrote:
Is there any simple way of getting round this?

A few:

1) Look at the ratings plate
2) Clamp meter
3) Using the lekky meter

I want to calculate power consumption during over a period,
so I'm not sure if these will work.
Incidentally, how does a Lecky (I assume that is what is meant) meter work?
Is it reasonably accurate?

In article ,
Timothy Murphy writes:

I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

Set top boxes are imfamous for not reducing power consumption
in standby mode, and are probably largely resposible for the
current standby hysteria. Most modern TV's reduce their standby
power to negligable levels in standby mode or they can't be
sold in a number of countries. How old is your TV?

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

Andrew Gabriel wrote:
In article ,
Timothy Murphy writes:
I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

Set top boxes are imfamous for not reducing power consumption
in standby mode, and are probably largely resposible for the
current standby hysteria. Most modern TV's reduce their standby
power to negligable levels in standby mode or they can't be
sold in a number of countries. How old is your TV?

Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.

--
Cheers,

John.

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| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 4 Oct, 09:04, John Rumm wrote:


Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.


Are you suggesting that the Aldi power meter is not a power meter?

T.

wrote:
On 4 Oct, 09:04, John Rumm wrote:

Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.


Are you suggesting that the Aldi power meter is not a power meter?

No, what I was highlighting is that the write up for it offers no clues
as whether it is able to distinguish between real and apparent power
consumption[1] - so take readings taken on this sort of kit with a good
degree of scepticism.

[1] Unlike the Maplin equivalent device for example which measures the
power factor of the load and makes allowances for it. Note however that
even this one does not work well on small capacitive loads.

--
Cheers,

John.

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

On 4 Oct, 11:08, John Rumm wrote:
wrote:
On 4 Oct, 09:04, John Rumm wrote:

Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.

Are you suggesting that the Aldi power meter is not a power meter?

No, what I was highlighting is that the write up for it offers no clues
as whether it is able to distinguish between real and apparent power
consumption[1] - so take readings taken on this sort of kit with a good
degree of scepticism.

[1] Unlike the Maplin equivalent device for example which measures the
power factor of the load and makes allowances for it. Note however that
even this one does not work well on small capacitive loads.


I'm afraid I don't fully understand. A device consuming 20W will do so
irrespective of the power factor. A power meter should measure this
power, just as my electricity meter does. What does making allowances
for pf mean?

T

John Rumm wrote:
Are you suggesting that the Aldi power meter is not a power meter?

No, what I was highlighting is that the write up for it offers no clues
as whether it is able to distinguish between real and apparent power
consumption[1] - so take readings taken on this sort of kit with a good
degree of scepticism.

[1] Unlike the Maplin equivalent device for example which measures the
power factor of the load and makes allowances for it. Note however that
even this one does not work well on small capacitive loads.

Actually, I see that the Aldi meter does show the power factor -
0.99 in this case.

John Rumm wrote:

Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.

Have you seen the Aldi power meter?
It actually seems quite sophisticated,
certainly more so than the Maplin meter (which I have also used).
Eg the manual is difficult to follow ...

Timothy Murphy wrote:
John Rumm wrote:

Also, as commented at the time, the Aldi power meter does not look like
it understand power factors. So lightly loaded switched mode supplies
(which often exhibit very poor power factors) could over-read
significantly.

Have you seen the Aldi power meter?
It actually seems quite sophisticated,
certainly more so than the Maplin meter (which I have also used).
Eg the manual is difficult to follow ...

I saw the one that someone linked to a little while back (can't follow
the link now since they seem to have removed the special offer) - that
one looked fairly basic and did not mention an ability to measure the
power factor. Yours may be better - or the advert may have left out a
bunch of features.


--
Cheers,

John.

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

Andrew Gabriel wrote:
In article ,
Timothy Murphy writes:
I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

Set top boxes are imfamous for not reducing power consumption
in standby mode, and are probably largely resposible for the
current standby hysteria.

A chum used to design cable set top boxes. He said that when the box
was put into standby mode two things happened :

video and sound outputs were stopped
an led came on to indicate the box was in standby mode

No power saving at all.

Guy
-- --------------------------------------------------------------------
Guy Dawson I.T. Manager Crossflight Ltd

Andrew Gabriel wrote:

I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

Set top boxes are imfamous for not reducing power consumption
in standby mode, and are probably largely resposible for the
current standby hysteria. Most modern TV's reduce their standby
power to negligable levels in standby mode or they can't be
sold in a number of countries. How old is your TV?

It's a Sony 26in TV (not flat screen), about 8 years old I think.
On re-checking I see that it only takes 12 watts in standby,
while the Grundig Sky box takes 30 watts.

Actually, I don't see any way of putting the Sky box on standy -
this is the consumption with the TV off.

In message , Timothy Murphy
writes
Actually, I don't see any way of putting the Sky box on standy

what happens when you press the button at the top right of the remote
control?

--
Si

Si wrote:

Actually, I don't see any way of putting the Sky box on standby

what happens when you press the button at the top right of the remote
control?

This doesn't seem to affect power consumption in the slightest -
it remains just under 30 watts (with the TV off),
though the light on the Sky box turns from green to red.

In article ,
Timothy Murphy writes:
Andrew Gabriel wrote:

I recently bought Aldi's power meter,
which I have found quite instructive -
I was surprised that my Sky box and TV
took 20 watts each in standby.

Set top boxes are imfamous for not reducing power consumption
in standby mode, and are probably largely resposible for the
current standby hysteria. Most modern TV's reduce their standby
power to negligable levels in standby mode or they can't be
sold in a number of countries. How old is your TV?

It's a Sony 26in TV (not flat screen), about 8 years old I think.
On re-checking I see that it only takes 12 watts in standby,

Just checked a 2 year old Panasonic LCD, and it's 0.5W standby.
It doesn't have a TCO'03 sticker on it, but this brings it within
the TCO'03 requirements (1W max standby) and thus able to be sold
in some countries where that's a requirement.

while the Grundig Sky box takes 30 watts.

That seems an awful lot, or the power meter is not handling
loads with power factor 1 correctly.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]