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Ermin
04/29/2000, 05:34 AM
Can AC box fan be "tuned" to slow down? If so, how can it be done? I also have 12v fans that I just turn down the output voltage of my converter to 9v or 6v to slow it down. Can AC fans be done the same?

If not, can and if so, how do I connect a AC fan to a thermometer. Here is what I want to do: If I set thermometer at 83 degrees, it senses the temp and complete the circuit turn the fan on at the temp.

I know Icecap has similar fans now, but I just want to DIY what I already have instead of spending on new fans.

jimhobbs
04/29/2000, 05:46 AM
You can DIY with a conroller that will cycle the fans off/on for about 45.00$; but it wont be variable speed, as the icecap units operate...I'm not aware of the going rate for the icecap fans, but the fact they are variable in speed is appealing...It would be interesting to hear from someone who actually uses them concerning the operational habits of the units...{IE- do they ramp up and stay at the same speed all day?...OR, do they speed up, cool the area down, then quieten down at a reduced speed?}...Only someone who has used them could provide this data... :)

Best regards...jim

Larry M
04/29/2000, 06:04 AM
Ermin--I had some luck for a while using a speed control for a ceiling fan on my hood fans. It worked after a fashion.

Jim--I have one of the IceCap fans in my new setup. It's hard to say how often it changes speed because it's so quiet..you can barely hear it running. I do know that the variable speed feature works though, when we got the fan my wife squeezed the sensor in her hot little paw and you could hear it pick up speed. Pretty sweet fans, IMO.

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Larry M

See my tanks at Northern Reef (http://www.reefcentral.com/northernreef/index.htm)

TheDonger
04/29/2000, 08:37 AM
I've been using a ceiling rheostat from Home Depot on my 4 AC fans. They are about $10 each.

Make sure if you go this route to get the fully controllable FAN rheostat. Not light rheostat.

They work great and you can tune the fan to the exactly liking for decibals and noise.

Also, I would buy an electrical box like you put outlets in for the rheostat, just like your wall sockets, and a face plate, then make sure no metal is exposed with eletrical tape if necessary. This is to avoid grounding on something and blowing a fuse somewhere.

Keith

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Visit Keith's Reef (http://www.keithsreef.com)

[This message has been edited by TheDonger (edited 04-29-2000).]

Ermin
05/05/2000, 04:54 AM
I got myself a fan controller to control the speed of the 4" box fan...but it didn't work.

According to the sales person at Home Depot...here's the deal.... Ceiling fans has built-in motor wounded 3 separate ways. High, med, and low. The fan controller is acting like a "remote" switch to do the job. The mechanism is actually in the ceiling fan. As a result, it wouldn't work on the box fan.... He doesn't know what to do in my case. Any suggestion if I want to control the speed of the fan? Thanks!

jimhobbs
05/05/2000, 05:07 AM
I don't think you will be able to do this successfully with an AC motor...I'd be interested in seeing the one that Keith is using...The way I understand it; when you reduce the voltage, the amperage will go up, and the motor will overheat...I'm not an electrician,; but seem to recall that it requires a DC motor to facilitate reduction in speed...Someone with an icecap set of fans should be able to do some simple tests to check this out...As usual, I'm subject to error! ;) Someone else will have to go into it deeper...Best regards...jim :)

[This message has been edited by jimhobbs (edited 05-05-2000).]

DSB
05/05/2000, 06:24 AM
I've been using a ceiling fan controller, like Keith is using, for several months now. It is a three speed switch I bought at Walmart. I've been running two RS 4" AC fans on the one switch at the lowest speed and it seems to be working fine. I haven't checked the temp of the fans after continued use though.

The rest of my fans are hooked to a Ranco temp controller so my tank is pretty quiet most of the time, even with the two fans continuously running on low.

Playfair
05/05/2000, 07:03 AM
I also have tried a ceiling fan speed control to no avail (perhaps wrong type?)

I found a variable transformer at a surplus place which works great to control fan speed. Since these may be hard to locate, perhaps just an AC transformer will suffice. I find the fans run quiet at about 60-75 volts AC.

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Mistress Reef (http://www.fortunecity.com/petparade/fins/1/reef.html)

Larry M
05/05/2000, 07:23 AM
If you take a look at my post, you will see I said it worked "after a fashion". Basically what it did was turn the fan into a two speed instead of a three speed like it was supposed to. So I had some success with it, but it did not work the way it should have.

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Larry M

See my tanks at Northern Reef (http://www.reefcentral.com/northernreef/index.htm)

ASH
05/05/2000, 07:34 AM
Note from IceCap, FAMA's May 2000 issue has a review on our variable speed fan reprinted on our site, www.icecapinc.com (http://www.icecapinc.com) .
I can see from this thread that more control of fans is still desired and will continue to investigate a water-temperature-controlled fan system.
Andy

[This message has been edited by ASH (edited 05-05-2000).]

Nathan
05/05/2000, 08:39 AM
Here is my review that I just posted on reefs.org:

---------------------------

Yes I bought two of these IceCap fans.
Here's what you get for $43 each:
- One 4 inch DC fan (very quiet in slow speed, but it does create some whirring sound at high to max speed)
- Transformer for fan with "quick disconnect" wires.
- Remote thermal sensor which can be placed near light bulb or near exhaust air exit.
I have a 75g with dual 400W and one single 175W MH bulbs. When the one 175W bulb comes on the fans don't increase speed much, but when one or two of the 400W bulbs fire, immediately the two fans adjust their speed accordingly.
Yeah $43 is kind of a lot, *but* you do get a transformer AND the thermal functionality.
Overall I love these fans, but with 975W under my hood they do produce a noticable whirr. I've never had any other fan to compare these to, except computer fans for my computers and appliances.
Hope that helps!

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And here is my second post:

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RobertK,
You are absolutely correct. Water temp is what we are trying to control. Air temp is the next best thing.
However for an easy one-stop-shop fan the IceCap was the one for me; simple and easy; no extra "bits to buy". It works (does keep my temp down proportionally to how many bubls are on).

-Nathan

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RobertK
05/05/2000, 12:28 PM
That would be great if Ice Cap could come out with a quiet (Papst?) fan with a built-in water temp sensor. I'll hold off on buying one til then.

TheDonger
05/05/2000, 02:02 PM
Finally got around to answering.

I use a FULLY controllable ceiling fan rheostat. Not a three-speed one.

It is $10 at Lowes/Home Depot. It has three wires. The main lead, which is the input and output, and a negative (sort of ground). 3 wires total on the rheostat. I split the two wires (lamp cord) so you have the ends with two wires on it. I then cut the lamp cord a couple of feet from the end. So you have 2-2 wire pieces to splice to the rheostat.

Then, I take the one wire (use the same one to be consistent, like the one with markings on the wire) and connect that single piece to the one power lead. Then the other lamp cord wire with the same marking goes to the other power lead which the fan rheostat controls coming out. I then take the two other wires on the cord and connect both to the negtive wire (attached to the rheostat metal) on the rheostat. So, you have one constant negative (not a ground) that connects to the rheostat body.

So you have, 1-wire connect to the rheostat input (Standard twist cap on the 2 wires), 1-wire connected to the output, then 2 wires connected to the rheostat body black wire (3 total wires connected including the negative on the rheostat with a twist cap. I install that in a standard plastic wall outlet that goes in your drywall for 97 cents. I then put a face plate on it like normal, and make sure all metal pieces of the rheostat are covered with eletrical tape (had one touch my pump once and pooooffff, blew the GFCI).

Anyway, I don't have a photo of them on my site, but you wouldn't see the wire anyway.

I have 2-3" and 2-4" Radio Shack AC fans connected this way in my hood (pics on site) using simple extension 2-wire wiring with the female extension cut off the end for loose wire and fully controllable ceiling fans rheostats. Each fan has one of these.

Does that make any sense? You have a positive and a negative line. No ground. If you hook it up wrong, it will go poof, and sparks will fly. That only makes sense.

Let me clarify one other thing. This isn't a temperature sensitive switch or anything. Just a rheostat to control the AC power going to the fan so I can control the RPM of the fan motor, thus the noise.

Keith

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Visit Keith's Reef (http://www.keithsreef.com)



[This message has been edited by TheDonger (edited 05-05-2000).]

jimhobbs
05/05/2000, 03:12 PM
Hey Keith... :)
Thanks for the clarification post! :) How long has this system be set up in this manner?...Have you ever measured the amp draw across either line with a clamp-on meter?...I'm just curious how the motors are holding up... :)

Best regards...jim

Ermin
05/05/2000, 04:19 PM
Keith,

If at all possible, can you please post the UPC code of the fully controllable rheostat?

I have only seen the 3-speed one at my local Home Depot.

Thanks!

fishpoo
05/05/2000, 05:16 PM
:)fwiw.
i took an old whisper 800 apart and took the control out. i used it to control the speed of a 110volt 4"fan. it worked great. however, it felt very hot and i was afraid of possible fire, so after a week i disconnected it. tom

TheDonger
05/05/2000, 08:03 PM
Jim,

5 months for the 3" fans. One 3" fan for 18 months before I got halides. The 2-4" fans for about 2 months. They run wide open though because they are quiet, don't need the rheostat, just nice to have in case.

I never have put a meter on the line. I run the 2-3" fans probably 80% of potential RPMs, and they just keep starting and working, no problems.

My brother uses this same method with a 3" Radio Shack fan and his stereo equipment, has had it this way for a year.

Ermin,

I have no idea what the UPC is. Both Lowe's and Home Depot should have the fully controllable fan rheostat that you can put in your wall socket to control the fan. Look a little closer, I can't believe they don't have them for $10. Remember, wire carefully, I could probably draw up a diagram if I had to, but email me if I need to go that far.

Keith



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Visit Keith's Reef (http://www.keithsreef.com)

TheDonger
05/05/2000, 08:15 PM
Okay, here is a photo to give you a better idea of what I did. Notice the electrical tape over the rheostat knob. My daughter used to pick them up and twist the knobs, leading to tank overheat! Total cost is about $14 for each. Rheostat ($10), extension cord ($3, depending on length), face plate(.47) and socket wall box ($1). Fan not included or electrical tape.

http://www.keithsreef.com/images/lights/fancontrol05042000.jpg

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Visit Keith's Reef (http://www.keithsreef.com)



[This message has been edited by TheDonger (edited 05-05-2000).]

DSB
05/05/2000, 08:15 PM
OK, I just did a heat check on my two 4" fans that have been running on low continuously for 5 hours now. Neither the fans nor speed controller are hot at all. The controller has three wires. One is a ground. I hooked it up by cutting the hot wire to the fans and simply wired it into this hot wire splice. I did not hook up the ground wire because I didn't have one going to the fans.

The speed controller is a Leviton Trimatron 1.5 Amp for ceiling fans from Walmart. I thought it was a three speed in my earlier post but it is actually a four speed. It has been hooked to the fans for about four months now.

There is a warning in the instructions stating "For use on ceiling paddle fans with split capacitor or shaded pole motors only." ... "Use with any other types of motors or equipment may cause overheating and/or damage to the motors or equipment." So, I guess I don't recommend anyone else to use one :)

Yam
05/05/2000, 10:42 PM
Here is a link to a data sheet that describes exactly what Icecap does. Maybe they're using this one.
http://www.micrel.com/_PDF/mic502.pdf

Danny

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http://www.ereefers.homepage.com

Larry M
05/05/2000, 11:03 PM
Andy, I would agree that as slick as your fans are, having the speed dependant on water temp instead of air temp would be ideal.

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Larry M

See my tanks at Northern Reef (http://www.reefcentral.com/northernreef/index.htm)

greasefire
05/05/2000, 11:31 PM
HI Ermin, you saw this when you came up to my house. I use standard light dimmers. I know it might not be the perfect solution but allmost 2 years on the exaust fan and no prob. I think that controlling with a ranco controller would rule but that's another $$$$. HTH JK

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http://www.blueoceandesigns.com

Ermin
05/06/2000, 04:05 AM
Keith,
I did look very carefully at the selection of controller at Home Depot. Probably just the branch close to my house missing the type of controller I wanted. They have only one kind of fan controller, but with 7-8 kinds of controller for lighting. I guess I'll go to another HD to see if they have it.

If I understood the wiring correctly:
The three speed fan controller has 3 wires. Green is left untouched. The other two connects to the cut fan wire, using the controller as the switch in the loop. Essentially two wires from the fan to the powerplug. One is left alone, the other has the break connected to the controller. The controller thus complete or breaks the circuit. Correct?

DSB,
I'll take a look at the controller you've mentioned when I have the chance to go to Walmart.

Greasefire,
I did try a light controller (about $3) from Home Depot. All the fan did was turn at about 1 revolution per 4 sec. Something is wrong with the type of circuitry on the light controller...just not an electrican to know "what exactly"...

Everyone, thanks for all the information!

[This message has been edited by Ermin (edited 05-06-2000).]

TheDonger
05/06/2000, 07:06 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR>Originally posted by Ermin:
Keith,

If I understood the wiring correctly:
The three speed fan controller has 3 wires. Green is left untouched. The other two connects to the cut fan wire, using the controller as the switch in the loop. Essentially two wires from the fan to the powerplug. One is left alone, the other has the break connected to the controller. The controller thus complete or breaks the circuit. Correct?

DSB,
[/B]<HR></BLOCKQUOTE>

Close. I cut the lamp cord about 2feet off the end. The long piece connects to the fan 2-wires of course. The green lead that goes in the rheostat has one of those lead connected to it. The other piece (short piece) has the same wire markings connected to the other green out lead on the rheostat. You will have three wires left over now. One is connected to the rheostat body to the metal. And, the long lamp cord has one wire free, and the short lamp cord piece has one wire free. Tak the two free wires on the pieces and connect those to the one connected to the rheostat body (3-way connect.) Only two wire are connected together on the input, and the output rheostat control. Make sense?

That is why I say be careful. The one lamp cord wire with markings (that is just how I keep it straight) goes from the positive side of the wall outlet, to the rheostat green in, then comes out the rheostat green out to the fan. The other lamp cord with markings goes to the other green out on the rheostat.

Ok, I think you get the point. If not, just reset the circuit breaker when it blows in your house if you get it wrong..hehe Of course, keep your receipt, if it blows, the rheostat will probably been ruined if you get the wiring wrong, return for an exchange. Take it from me, I learned that way unfortunately because I wasn't thinking.

Keith


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[This message has been edited by TheDonger (edited 05-06-2000).]