"Lurch" wrote in message
...
On Sun, 09 Jan 2005 20:06:43 +0000, Richard strung
together this:
Simple when I stop thinking about latching or changeover relays with
mains coils and how to power them!
Always best to stop thinking if you want to work something out!
I suppose however I could use a pair
of SPDT latching relays if I could find a momentary pull switch,
Well, I think standard 230VAC relays would be the easiest to source,
as would be a 1 way pull switch as opposed to a momentary one. I know
that I could walk into my local CEF tomorrow and get all the bitsd I'd
need to do the job.
thus
extending the life of any battery derived coil supply.
I'd use mains relays and power them from the lighting circuit,for the
sake of running a neutral in from the lighting circuit it's better
than having batteries.
The only thing about using a relay, is that the solenoid coil in the relay would
have to stay on in one position, when switched. If left for a long period, the
coil may create enough heat to either the enamel on the coil and blow fuses, or
to cause a fire in surrounding materials when the relay housing melts. I
personally don't think a relay is the way to go, unless you can source one that
is designed to be left energised for long, long periods of time.
The wiring could be configured to make the switch positions different. The now
intermediate switch could be placed at one of the points where a two way switch
is now. We already have four conductors at the intermediate position, so you
could fit a two way to this point and use the remaining conductor a pass through
to one of the other points and make it into a intermediate switch point.
We need to know how the light fitting is connected to the switching system.
Things like, does the negative also enter at one of the switch points? Does the
live feed to the light fitting come from the opposite end of the circuit from
the supply?
Where does the light fitting pick up its negative? Are there any pass wires
already coming through any switch points?
More input. :-)
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