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Default How do light switch security timers work?

A friend asked me to have a look at a Superswitch 2304 timer which
stopped working when the bulb which it was switching blew, and replacing
the bulb didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal
3A fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live
and switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light
on, the live and switched live would be at the same voltage and wouldn't
be able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?
--
Cheers,
Roger
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Default How do light switch security timers work?

On Wed, 26 Apr 2017 23:31:44 +0100, Roger Mills
wrote:

A friend asked me to have a look at a Superswitch 2304 timer which
stopped working when the bulb which it was switching blew, and replacing
the bulb didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal
3A fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live
and switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light
on, the live and switched live would be at the same voltage and wouldn't
be able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?


A battery or supercapacitor.

--

Graham.
%Profound_observation%
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Default How do light switch security timers work?

Are you sure its not a simple bimetal strip in an enclosure in series with
the bulb? I have one like that but in order for it to work with CFLs they
have to be over 8 watt apparently, don't know about leds.
Brian

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"Roger Mills" wrote in message
...
A friend asked me to have a look at a Superswitch 2304 timer which stopped
working when the bulb which it was switching blew, and replacing the bulb
didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal 3A
fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live and
switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light on,
the live and switched live would be at the same voltage and wouldn't be
able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?
--
Cheers,
Roger
____________
Please reply to Newsgroup. Whilst email address is valid, it is seldom
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Default How do light switch security timers work?

Roger Mills submitted this idea :
Clearly, I must be missing something! Anybody know what?


When the switch is off, there is potential/ voltage across the two
terminals. That potential charges either a tiny battery, or a
specialised capacitor so it has a power source when the light is on and
there is no potential across the switch.

Most likely problem if the fuse has been blown by the lamp, is that the
Triac has also been blown or possibly the relay, if it uses a relay for
switching.
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Default How do light switch security timers work?

Harry Bloomfield wrote:
Roger Mills submitted this idea :
Clearly, I must be missing something! Anybody know what?


When the switch is off, there is potential/ voltage across the two
terminals. That potential charges either a tiny battery, or a
specialised capacitor so it has a power source when the light is on and
there is no potential across the switch.

Most likely problem if the fuse has been blown by the lamp, is that the
Triac has also been blown or possibly the relay, if it uses a relay for
switching.

Even when the lamp appears to be on the capacitor can be charged during
the first few degrees of each cycle without any noticeable effect on the
lamp brightness.


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Default How do light switch security timers work?


"Roger Mills" wrote in message
...
A friend asked me to have a look at a Superswitch 2304 timer which stopped
working when the bulb which it was switching blew, and replacing the bulb
didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal 3A
fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live and
switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light on,
the live and switched live would be at the same voltage and wouldn't be
able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?


According to the manual, it has an internal rechargeable battery that needs
2 hours with switch turned ON to charge from cold, and then gives 24 hour
backup. When ON there must be a small voltage drop across the unit high
enough to supply the charging current, and the display is run from the
battery at all times. The 400W max bulb would take 1.7A, so if the voltage
drop across the unit is say 1.5V to be able to charge an NmH cell, less than
3W is dissipated in the unit. The small voltage is what might be expected
across a triac when conducting.
--
Dave W


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Default How do light switch security timers work?

On 26/04/2017 23:31, Roger Mills wrote:
A friend asked me to have a look at a Superswitch 2304 timer which
stopped working when the bulb which it was switching blew, and replacing
the bulb didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal
3A fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live
and switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light
on, the live and switched live would be at the same voltage and wouldn't
be able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?



Yup you are right, it draws its power through the lamp (hence the
filament lamp restriction). Its a very low level current draw and hence
not enough to light the "off" lamp.

As to how its powered while the lamp is on, there are several ways it is
done - depending a bit on the switch design. One option is to just keep
a backup power source charged when the lamp is off. However that is sub
optimal since you don't know how long the lamp will be on for, and
whether there is sufficient "off" time to keep it charged. Better
options will still allow it to draw power when the lamp is on, usually
at the expense of dropping a small voltage in the switch.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/
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Default How do light switch security timers work?

On 27/04/2017 12:41, John Rumm wrote:
On 26/04/2017 23:31, Roger Mills wrote:
A friend asked me to have a look at a Superswitch 2304 timer which
stopped working when the bulb which it was switching blew, and replacing
the bulb didn't fix it.

The answer, of course, was that when the bulb blew, so did an internal
3A fuse in the timer.

But, having had a look at the thing, I don't understand how it works. It
replaces a conventional wall switch and only has 2 connections - live
and switched live. Yet the thing itself needs power to operate the
display/logic/relay, etc. - and it doesn't have a neutral connection. My
first thought was that maybe it gets a connection from an earthed
backbox - but the holding screws go through insulated sleeves, and don't
connect to the circuit board.

My next thought was that it could get a neutral connection through the
bulb (it apparently only works with tungsten bulbs). But surely, that
would only work when the light was off. Once it had switched the light
on, the live and switched live would be at the same voltage and wouldn't
be able to power it to do any further timing/displaying/switching.

Clearly, I must be missing something! Anybody know what?



Yup you are right, it draws its power through the lamp (hence the
filament lamp restriction). Its a very low level current draw and hence
not enough to light the "off" lamp.

As to how its powered while the lamp is on, there are several ways it is
done - depending a bit on the switch design. One option is to just keep
a backup power source charged when the lamp is off. However that is sub
optimal since you don't know how long the lamp will be on for, and
whether there is sufficient "off" time to keep it charged. Better
options will still allow it to draw power when the lamp is on, usually
at the expense of dropping a small voltage in the switch.



Thanks for all the replies.

I can't see anything which looks like a battery in it - but it does have
a 6.3v 1000 uF capacitor (the blue one towards to bottom RH corner of
https://app.box.com/s/no8ccg03hf7yr2f8odqlfw9r03fael5z) which may well
store some energy.

I don't know whether it would still work if I replaced the fuse - I
didn't have a 3A BS646 fuse to hand - and my friend asked me to replace
it with a simple on/off switch, so I haven't had an opportunity to test it.
--
Cheers,
Roger
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Default How do light switch security timers work?

replying to Roger Mills, Eamonn wrote:
Iam not sure either but I have a Superswitch 2304 for about 15 years and now
the LCD is unreadable so I cannot set the time.
Do you remember how to reorder this switch as I have been very happy with it
up to now, also my swith has 3 connection terminals at the back
Regards
Eamonn


--
for full context, visit https://www.homeownershub.com/uk-diy...k-1205175-.htm


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Default How do light switch security timers work?



Brian Gaff (Sofa 2) wrote

How old is this one I wonder.


Not even 3 years, a mere toddler.


"Eamonn" m wrote in
message oupdirect.com...
replying to Roger Mills, Eamonn wrote:
Iam not sure either but I have a Superswitch 2304 for about 15 years and
now
the LCD is unreadable so I cannot set the time.
Do you remember how to reorder this switch as I have been very happy with
it
up to now, also my swith has 3 connection terminals at the back
Regards
Eamonn


--
for full context, visit
https://www.homeownershub.com/uk-diy...k-1205175-.htm



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Default Lonely Auto-contradicting Psychotic Senile Ozzie Troll Alert! LOL

On Tue, 11 Feb 2020 08:24:15 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


How old is this one I wonder.


Not even 3 years, a mere toddler.


If someone wanted to hear an asshole, they'd have farted, senile asshole!

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Default How do light switch security timers work?

That should have lasted longer than it did. I think I'd send it back and act
a built dumb saying how you feel they really should know about this problem,
and they may take pity and send you a new one.
I had a thermometer gadget like this some years ago and the company sent
me a new one and the new one lasted 10 years, so the first one obviously had
a crap display from the start. Of course now I like talking thermometers
etc, and now we have other issues with one no longer saying the decimal
point only the degrees. You just cannot get reliable tech these days. grin.
Brian

--
----- --
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"Rod Speed" wrote in message
...


Brian Gaff (Sofa 2) wrote

How old is this one I wonder.


Not even 3 years, a mere toddler.


"Eamonn" m wrote in
message
oupdirect.com...
replying to Roger Mills, Eamonn wrote:
Iam not sure either but I have a Superswitch 2304 for about 15 years and
now
the LCD is unreadable so I cannot set the time.
Do you remember how to reorder this switch as I have been very happy
with it
up to now, also my swith has 3 connection terminals at the back
Regards
Eamonn


--
for full context, visit
https://www.homeownershub.com/uk-diy...k-1205175-.htm





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Default How do light switch security timers work?

Brian Gaff (Sofa 2) wrote

That should have lasted longer than it did. I think I'd send it back and
act a built dumb saying how you feel they really should know about this
problem, and they may take pity and send you a new one.


Yeah, I sent a not very polite email to the manufacturer of
one of these which had failed outside the stated warranty
and was a bit surprised to have them send me a new one.
Culinare One Touch Automatic Jar Opener

And another when that one failed. Which reminds me, the latest has failed
too.
They don’t seem to be able to make it strong enough.

I had a thermometer gadget like this some years ago and the company sent
me a new one and the new one lasted 10 years, so the first one obviously
had a crap display from the start. Of course now I like talking
thermometers etc, and now we have other issues with one no longer saying
the decimal point only the degrees. You just cannot get reliable tech
these days. grin.


Your iphone leaves the previous phones for dead.

Havent had any failures with the Hue lights or the alexa or
google home mini either and I have a few of them now.

"Rod Speed" wrote in message
...


Brian Gaff (Sofa 2) wrote

How old is this one I wonder.


Not even 3 years, a mere toddler.


"Eamonn" m wrote in
message
oupdirect.com...
replying to Roger Mills, Eamonn wrote:
Iam not sure either but I have a Superswitch 2304 for about 15 years
and now
the LCD is unreadable so I cannot set the time.
Do you remember how to reorder this switch as I have been very happy
with it
up to now, also my swith has 3 connection terminals at the back
Regards
Eamonn


--
for full context, visit
https://www.homeownershub.com/uk-diy...k-1205175-.htm





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Default Lonely Auto-contradicting Psychotic Senile Ozzie Troll Alert! LOL

On Wed, 12 Feb 2020 04:32:25 +1100, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:


Yeah, I sent a not very polite email to the manufacturer of


What a "surprise", you cantankerous, senile auto-contradictor! LMAO

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