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Thread ID: 92042	2008-07-26 23:49:00	Using PIR sensor unconventionally for controlling bathroom extractor fan	Johnnz (7246)	PC World Chat

Post ID	Timestamp	Content	User
692554	2008-07-28 02:48:00	Why not just have a separate switch for the fan? everyone I know with one just does that...	Agent_24 (57)
692555	2008-07-28 06:08:00	Now where's the fun in that? :nerd: :D	Johnnz (7246)
692556	2008-07-28 06:20:00	"Keep it simple" is a very good rule. A simple switch that an electrician can understand will work. Every time. A simple thermostatic switch fixed to a hot water pipe should work every time. The PIR won't work without a lot of work. It probably won't ever work properly pointed at the pipe. It's designed to do a completely different task. All the movement detection PIRs I've seen need the moving of the target to create the signal which is amplified to produce the required action. The pipe doesn't move. If you must use a PIR, point it so it sees the moving body in the shower. Silicon Chip had a project a while ago which detected the noise of the water and turned it off after four minutes or so for power (and water) economy. That would work better than the PIR. I still think I'd use a switch to activate a fan. If I wanted to impress the natives with technological magic which worked, I'd use a thermostatic switch on the pipe. I would not use a PIR, even to impress the natives with technological magic which didn't work.	Graham L (2)
692557	2008-07-29 05:28:00	Thanks for the tips about PIR's being unsuitable. I have just completed the installation of the extractor fan this afternoon (currently just wired into the light switch) and tested it having a shower. It certainly does the job - it felt really quite drafty in there and the vanity mirror never fogged up which is a first. Walls dry too. Although the outside temp was a rather mild 7 degrees there was a lot of condensation dripping down inside the grill, so all in all it is very effective. (positioned on the wall inside shower cubicle about 50mm below the ceiling). By the way this is a Manrose 150mm 12vac fan. Although this is a pretty good system as is, I still plan to make up the kitset I posted early (temperature switch). Although it isn't necessary of course, I haven't done a kitset for ages and it should help to refresh and expand a bit of my electronics knowledge. I ordered it yesterday from Jaycar and it turned up today! Record time for anything i have ever ordered. Only paid for parcel post too. Will update this thread when I get it done.	Johnnz (7246)
692558	2008-07-29 05:32:00	By the way this is a Manrose 150mm 12vac fan. Glad to hear that it does shift some air. What sort of price is the 12vac version?	PaulD (232)
692559	2008-07-29 06:02:00	I ordered it yesterday from Jaycar and it turned up today! Record time for anything i have ever ordered . Only paid for parcel post too . Sounds right to me, if you paid the same day you ordered (eg: credit/debit card) and parcelpost is now done via courier anyway .	Agent_24 (57)
692560	2008-07-29 09:25:00	Glad to hear that it does shift some air. What sort of price is the 12vac version? Got it for $133 from Redpaths. Outside grill was half the price of Placemakers there too. Yes, I am pleased about the result too. We have 100mm 240v Manrose fans through the rest of the house and they don't do jack.	Johnnz (7246)
692561	2008-07-29 09:53:00	[QUOTE=Graham L;698476]"Keep it simple" is a very good rule . . . . . . . . . . . . . . . . . . detected the noise of the water and turned it off after four minutes or so for power (and water) economy . That would work better than the PIR . But every time you went to the toilet,the shower would come on! :D :D	BobM (1138)
692562	2008-07-30 01:05:00	I use 10" 230v fans from Bunnings, under $25...	godfather (25)
692563	2008-07-30 03:08:00	. . . But every time you went to the toilet,the shower would come on! :D :D With a Northern Hemisphere shower, you may produce a bidet .	R2x1 (4628)
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