Apt timer - light always on

Sleeper12

Have you any idea how it would need to be wired for this to happen? If each element is 3.5kw & you are saying it "

Ends up at 1.2kw" are you sending the same live to both elements? If its a stupid guess please don't laugh.

Bruthal

Yea the neutral of flex into bath terminal of switch for example
And bath wire of flex into neutral terminal of switch.

Select bath on switch and bath works properly although polarity is reversed.

Select sink though, and both elements on in series, with stat out of circuit.

2011

tpmcompany1 wrote: »

Have you any idea how it would need to be wired for this to happen?

Do the maths.

Remember the power = VI (taking the power factor to be unity)

As V is fixed the power is directly portional to the current.
But the current is inversely proportional to the resistance.
If both elements are connected in series the resistance increases, so the current decreases and the power decreases.

Sleeper12

Got ya. thanks for the reply. And thanks Bruthal too.

Bruthal

Yea I didnt notice the second part of the question you asked as i was replying on the phone. 2011 answered that anyway.

Its all just as a matter of interest, but here is a rough drawing of the circuit incorrectly connected as I described. You might be able to see the circuit via both elements in series, and the stat gets bypassed, when sink is selected as per diagram. Blue is connected to bath terminal, brown to neutral, black to sink (for black sink brown bath flex).

Select bath and that works properly.


And correctly connected.

Sleeper12

Bruthal wrote: »

Yea I didnt notice the second part of the question you asked as i was replying on the phone. 2011 answered that anyway.

Its all just as a matter of interest, but here is a rough drawing of the circuit incorrectly connected as I described. You might be able to see the circuit via both elements in series, and the stat gets bypassed, when sink is selected as per diagram. Blue is connected to bath terminal, brown to neutral, black to sink (for black sink brown bath flex).

Select bath and that works properly.


And correctly connected.

The diagram helped a lot. Thanks

Bruthal

The ms paint is handy for some things:)

Robbie.G

Bruthal wrote: »

It's actually possible to connect immersion flex incorrectly at the switch and bypass the immersion stat. Ends up at 1.2kw with both elements in series. Never seen it happen though.

What I have come across lately is where a hortsmann e15 timer or similar is used some people are removing the dual switch and replacing directly with timer connecting both elements together in the switch.

tomdempsey200

Robbie.G wrote: »

What I have come across lately is where a hortsmann e15 timer or similar is used some people are removing the dual switch and replacing directly with timer connecting both elements together in the switch.

they won't be long getting called back with problems

Bruthal

Probably overloading the flex neutral a bit as well.

tomdempsey200

Bruthal wrote: »

Probably overloading the flex neutral a bit as well.

and they're not suitable as a switch replacement anyhow

even if you connect one

Bruthal

You'd have hot water for the sink and bath at the same time at least...
not really, in case anyone thinks I'm serious