PIR Problem

[charliefunkuk]

I 4 toilets which run off one single ducted fan in the top of the building. What I want to do is put occupancy sensors in all the toilets so when someone enters the lights go on only in that toilet and so does the common fan, all for a pre set time. If I use normal PIRs would I be right in saying that if I walked in one toilet it would work as above but also the lights in all the other toilets would go on as well?

Is there such thing as a PIR with 2 outputs? If so where? Failing that the only other solution I can think of is using 2 PIRs in each toilet which seems a little overkill and expensive.

Any ideas please?

Neil

 

[maguire]

You can have a slave occupancy sensor off the main sensor, I take it each toilet has a single light switch and only controls one light in one toilet
but unless your absolutly confident in whats required I'd seek pro advice
DM

 

[Taylortwocities]

You are probably going to need a relay off each PIR. The relay will need two NO contacts, one to operate the lights and one to turn on the central fan.

IMO PIRs in toilets are a bad idea as you can get plunged into darkness if you are having a long contemplation...

 

[ebee]

"contemplation..."

Ohh that's a good word!

 

[Taylortwocities]

Had a thought (contemplation)

Why not keep the lights on their time switch but have the fan on PIRs, one in each toilet.
Just parallel them up: make sure they are the type with a relay output, some have semi-conductor output which don't seem to like to be inter-connected.

 

[Lectrician]

You can get twin output occupency sensors, not sure where I saw them though....

You could use a relay to fire the fan - It would not need to be two pole (although they all are really) - the light and coil are switched by the PIR, the relay contacts activating the fan.

 

[electronicsuk]

Had a thought (contemplation)

Why not keep the lights on their time switch but have the fan on PIRs, one in each toilet.
Just parallel them up: make sure they are the type with a relay output, some have semi-conductor output which don't seem to like to be inter-connected.

Or, even better, keep the light switch but change it for a double pole version, so that one set of contacts can be used to control the fan. I'm assuming, of course, that being a flat the toilet only has a small window or perhaps no window at all, so the light will always be turned on when 'in use'.

 

[Lectrician]

Didn't think this was a flat?

I assumed a commercial install with a few toilets.....

 

[electronicsuk]

Didn't think this was a flat?

I assumed a commercial install with a few toilets.....

I swear I read flats somewhere, but reading back, it looks like I totally made it up!