I need a 2-pole bathroom pull switch with the following behaviour:
a. Quick pull/release causes toggle between ON and OFF of "pole 1"
b. A normally on "pole 2" with timed OFF (say 30 mins)

A quick pull/release should always cancel the timed OFF.
I wish to use this to disable my humidistat fan for a certain period of time, in order to stop it triggering due to a hot bath, etc. It needs to always revert to normal auto function, else the family will leave it switched off !

Any ideas without using an PIC / Rasperry PI, etc ?

Simon.

On 10/09/15 16:37, sm_jamieson wrote:
I need a 2-pole bathroom pull switch with the following behaviour:
a. Quick pull/release causes toggle between ON and OFF of "pole 1"
b. A normally on "pole 2" with timed OFF (say 30 mins)

A quick pull/release should always cancel the timed OFF.
I wish to use this to disable my humidistat fan for a certain period of time, in order to stop it triggering due to a hot bath, etc. It needs to always revert to normal auto function, else the family will leave it switched off !

Any ideas without using an PIC / Rasperry PI, etc ?

Simon.


The easiest way (IMO) would be to get a small enclosure, with a bit of
DIN rail and use a DIN timer module and, if necessary, a DIN relay to
achieve the required logic. Use a "Disabled alarm" pull cored switch,
these are SPST momentary action. Include a 2 pole (fused if required)
isolator feeding the whole lot.

Sometimes, trying to get "clever" with a Pi and mains is non trivial -
and DIN module relays and timers exists at Farnell and RS - and merely
need enclosing and wiring.

I am thinking of:

Feed fan through relay's "NC" contacts.

Feed relay coil from DIN timer.

Trigger DIN timer with pull cord.

That would be *very* simple to wire up in a box - and the timers are
dead common as they would be the sort used for delayed-on landing lights
in blocks of flats (assuming they go up to 30 mins).

On Thursday, September 10, 2015 at 5:09:49 PM UTC+1, Tim Watts wrote:
On 10/09/15 16:37, sm_jamieson wrote:
I need a 2-pole bathroom pull switch with the following behaviour:
a. Quick pull/release causes toggle between ON and OFF of "pole 1"
b. A normally on "pole 2" with timed OFF (say 30 mins)

A quick pull/release should always cancel the timed OFF.
I wish to use this to disable my humidistat fan for a certain period of time, in order to stop it triggering due to a hot bath, etc. It needs to always revert to normal auto function, else the family will leave it switched off !

Any ideas without using an PIC / Rasperry PI, etc ?

Simon.


The easiest way (IMO) would be to get a small enclosure, with a bit of
DIN rail and use a DIN timer module and, if necessary, a DIN relay to
achieve the required logic. Use a "Disabled alarm" pull cored switch,
these are SPST momentary action. Include a 2 pole (fused if required)
isolator feeding the whole lot.

Sometimes, trying to get "clever" with a Pi and mains is non trivial -
and DIN module relays and timers exists at Farnell and RS - and merely
need enclosing and wiring.

I am thinking of:

Feed fan through relay's "NC" contacts.

Feed relay coil from DIN timer.

Trigger DIN timer with pull cord.

That would be *very* simple to wire up in a box - and the timers are
dead common as they would be the sort used for delayed-on landing lights
in blocks of flats (assuming they go up to 30 mins).

I'll look at the DIN modules. I forgot to say, I was thinking of triggering the timed off from the same pullswitch, the trigger being a "long" pull, i..e. hold the momentary action in "make" position for say 5 seconds.

So, default mode is humidistat acting as normal - i.e. the new pull-switch doing nothing. Quick pull to override the humidistat into fan permanently ON. Another quick pull to cancel override. A long pull to disable fan for 30 minutes. Any time during the 30 minute disable period, a quick pull to put it back into normal mode.
A bonus might be that the override to ON is timed ...
You get the idea.

Simon.

On Thu, 10 Sep 2015 08:37:16 -0700 (PDT), sm_jamieson wrote:

I need a 2-pole bathroom pull switch with the following behaviour:
a. Quick pull/release causes toggle between ON and OFF of "pole 1"
b. A normally on "pole 2" with timed OFF (say 30 mins)

A quick pull/release should always cancel the timed OFF.
I wish to use this to disable my humidistat fan for a certain period of time, in order to stop it triggering due to a hot bath, etc. It needs to always revert to normal auto function, else the family will leave it switched off !

Any ideas without using an PIC / Rasperry PI, etc ?

Simon.

I did see one by MK(?) and it might have been a variation on the timed stair
lights - or not, can't recall now.
Somewhere I've a little timer and a diagram for just such a purpose. The
switch is an ordinary 2-way pull and the timer breaks the circuit and also
removes voltage from itself, then the changeover repeats the process. Can't
remember where it is now!
--
Peter.
The gods will stay away
whilst religions hold sway

sm_jamieson wrote:
I'll look at the DIN modules. I forgot to say, I was thinking of triggering the timed off from the same pullswitch, the trigger being a "long" pull, i.e. hold the momentary action in "make" position for say 5 seconds.

Are you using the pull switch just because it's a bathroom? If you make
the control side SELV (under 50V) you could use several push-buttons
which would make the logic simpler.
If it's too complex for relay logic i'd be looking at 555 timers and
74-series or 4000-series logic gates.

Mike

On Thursday, 10 September 2015 16:37:21 UTC+1, sm_jamieson wrote:
I need a 2-pole bathroom pull switch with the following behaviour:
a. Quick pull/release causes toggle between ON and OFF of "pole 1"
b. A normally on "pole 2" with timed OFF (say 30 mins)

A quick pull/release should always cancel the timed OFF.
I wish to use this to disable my humidistat fan for a certain period of time, in order to stop it triggering due to a hot bath, etc. It needs to always revert to normal auto function, else the family will leave it switched off !

Any ideas without using an PIC / Rasperry PI, etc ?

You could use a time delay relay. Or power the fan via a PIR detector, just reversing its switching function. A computer seems bizarre overcomplication.


NT