varying speed of a duct fan ?

Which model do you have in mind?

The two speeds built in are not sufficient?

It may be. Or the motor may be dual-wound, like a car wiper motor.

/Which model do you have in mind?

The two speeds built in are not sufficient? /q

There are loads about, this one say

EBay 111060416198

Speed:- I'd want more control, plus as I said it will be remotely mounted so how would I change standard speeds anyway?

Jim K

/ Is a speed controller like a dimmer switch?

It may be. Or the motor may be dual-wound, like a car wiper motor. /q

I was thinking of the separate control boxes with rotary knobs on that are available, something like that mounted in the kitchen remotely controlling the fan... are there gotchas with the approach?

Jim K

We have single speed in line duct fans and rotary fan controllers.

Think we bought them from TLC - alongside the fans.

They work well, but I suspect that you have to go for a fan controller matched to the individual fan to be sure they are O.K. together.

If you are running the fan from a variable speed controller then why do you need a two speed fan?

Thread(s) a couple of years ago discussing this when we installed them.

Cheers

Dave R

Depends on the motor. Most are induction and so really are fixed speed or two speed due to the way they are wound. Brian

If you look at that eBay listing, it includes a link to the installation instructions for that particular fan. It shows you how to wire it up so as to be able to use both speeds. There are 2 live terminals on the fan, and you can switch the live feed between them.

The installation instructions also show the setup for a variable speed controller.

You need to go to specsavers. :)

There are now some motors built a bit like the motor in a cd player, and these have electronic control, but they tend to be more expensive than the bog standard induction driven kind that rely on the cycles on the mains for their speed, hence only multiples of the mains AC speed are allowed. Brian

/The installation instructions also show the setup for a variable speed controller.

You need to go to specsavers. :) /q

Hehe

What's an "REB" as shown in the one diagram you refer to?

Jim K

Strewth that's a big jump from 10 to 120?!

Not exactly aesthetically pleasing either....

Jim K

It's a particular make of electronic fan controller. I assume that they alter the frequency of the AC. They come in different wattages/amperages, and they are quite expensive. Region of £40+. I assume the 1 amp version will do you.

Google REB fan controller, and you'll find them easily enough.

Personally, as this is a quiet fan anyway, I would just go for the two speeds built in. That just requires a two way switch and two wires. You will need access to the fan, as if you box it in completely Sod's Law says it will be bound to break.

I am controlling a similar fan using one of these

Its not the best way, the remote changes the speed too fast for precise setting but I just wanted a slower speed than the fan did. I have a lightwaverf mood controller that is set to do silent, medium and full speeds.

/It's a particular make of electronic fan controller. I assume that they alter the frequency of the AC. They come in different wattages/amperages, and they are quite expensive. Region of £40+. I assume the 1 amp version will do you.

Google REB fan controller, and you'll find them easily enough./q

Mmm lots of assuming going on all of a sudden ;^)

Besides a 2 way switch there'll need to be a master on off too?

Jim K

Indeed. I suggest that you ask for a refund of the fee you paid.

Yes, unless you find a switch that combines the two functions.

/> Mmm lots of assuming going on all of a sudden ;^)

Indeed. I suggest that you ask for a refund of the fee you paid. /q

Why bother at all then?

Jim K

Indeed. I won't make that mistake again. I'll make sure that I thoroughly research the internal workings of every duct fan and fan controller on the market. My abject apologies.

Er?? Touchy!

You asked me which make & model then you proceeded? Hardly a full "fan market precis" was it? Then came the caveats...

What happened? Did you catch yourself being nearly constructive?

(dont worry I'm sure you've caught yourself in plenty of time).

Thanks anyway

Jim K

I'm a bit lost, actually.

I checked for you which fan controller the manufacturers recommend and what the price is.

Then I said that I assumed the 1 amp version would do you. That was a bit vague, I admit. What I meant was that you should look up the spec of the fan and check that it takes under 1 amp.

You then got all uppity and suggested that I was not being helpful enough. That's weird. Why wouldn't you look up the fan spec yourself?

Why are you thanking me? I clearly haven't met your expectations.