Is it possible to dial down inline fans?

[Harry Gypsna]

I've known of dozens of people, who've used variacs to slow down inline centrifugal fans, the only problem I haver ever heard of was one guy who used an underrated variac.
I prefer the stepped transformer anyway
Also, I dont know if you get Vent-Axia equipment across the pond, they they make a couple of good controllers, the WAC-1 and WAC 6. EDIT-the WAC1 and WAC6 may be xpelair

 

[jm420]

For use with brush type motors, such as squirrel cage blowers. The Speedster will work with all exhaust fans listed within our web site, EXCEPT for the Can-Fan MAX fan.

http://www.4hydroponics.com/growroom/items.asp?ItemNo=speedster


Im using hydrofarm inlines. These are not blowers. The website says will work with all fans except Can Fan or max fan..

Is there a diferance between this one and the speedstar. This is is made by Hydrofarm active air. Im using these fans....
http://www.amazon.com/Hydrofarm-ACS...BQ1M/ref=sr_1_3?ie=UTF8&qid=1336710738&sr=8-3

I'm waiting on that answer from HF now .I bought the CAP controller and the motor hums like crazy .Come to find out this controller cannot be used with "brushless" fans wich the active air fans have "brushless" motors.Cap claimed it can be used with all inline fans as well.Then they place a sticker on the controll itself saying not for use with brushless motors.http://www.randmsupply.com/productdisp.php?pid=627&navid=33



The HF website says http://www.amazon.com/Hydrofarm-ACS...BQ1M/ref=sr_1_3?ie=UTF8&qid=1336710738&sr=8-3 this is the proper controll for active air fans,I'm sure that what the email will say .good find though ebay has the for 27 with free shipping

 

[rives]

I've known dozens of people, who've used variacs to slow down inline centrifugal fans, the only problem I haver ever heard of was one guy who used an underrated variac.
I prefer the stepped transformer anyway
Also, I dont know if you get Vent-Axia equipment across the pond, they they make a couple of good controllers, the WAC-1 and WAC 6.

Harry, as has been stated before in this thread, low voltage will shorten the life of an electric motor. There is some forgiveness built into a in-line fan motor because the air flowing over the motor inherently helps the cooling, but in industrial applications equipment is sized to keep voltage drops under 3%, and permanent damage starts occurring at 5%. A drop to 80% nameplate voltage will result in a drop in torque to less than 65% for most motors, increasing startup time and creating even more heat. Google low voltage and it's impact on motor life.

 

[Harry Gypsna]

Harry, as has been stated before in this thread, low voltage will shorten the life of an electric motor. There is some forgiveness built into a in-line fan motor because the air flowing over the motor inherently helps the cooling, but in industrial applications equipment is sized to keep voltage drops under 3%, and permanent damage starts occurring at 5%. A drop to 80% nameplate voltage will result in a drop in torque to less than 65% for most motors, increasing startup time and creating even more heat. Google low voltage and it's impact on motor life.

OK fair enough....but I will add that the main centrifugal fan manufacturers in europe (Systemair and Ruck) sell stepped voltage transformers for use with inline centrifugal fans.
I personally would choose reduced motor life over humming and buzzing caused by electronic speed controllers(it depends on your growing situation I guess), the fans are cheap enough to keep a spare in the sizes I use, cheaper than the controllers.
As long as someone understands it could reduce the life of the fan I don't see the issue as long as it does the job, I've never heard of a fan going boom or burning someones house down-the fan just dies(obviously the plants die with it if you don't have emergency measures such as overtemp alarms or backup fans in place).

 

[imnotcrazy]

OK fair enough....but I will add that the main centrifugal fan manufacturers in europe (Systemair and Ruck) sell stepped voltage transformers for use with inline centrifugal fans.
I personally would choose reduced motor life over humming and buzzing caused by electronic speed controllers(it depends on your growing situation I guess), the fans are cheap enough to keep a spare in the sizes I use, cheaper than the controllers.
As long as someone understands it could reduce the life of the fan I don't see the issue as long as it does the job, I've never heard of a fan going boom or burning someones house down-the fan just dies(obviously the plants die with it if you don't have emergency measures such as overtemp alarms or backup fans in place).

Unless something like this happens:

Ok so I was working on my new grow cab, which is 90% complete. While working, I was shocked by my Variac (Fan Speed Controller), which is connected to my inline-fan. After cutting off power from the surge protector, I went to analyze what went wrong. Even with power cut off, I was shocked once more when I touched the Variac, which means there's a live capacitor somewhere; either in the fan or the Variac; obviously fully charged at mains potential. Now I'm scared to even go near my setup, WTF am i supposed to do now??? Is it the fan that's fucked or the Variac? Fuk, why do stupid shit always happen to me?

MOST variacs are only fused on the primary and in this instance the "secondary" winding of the variac short circuited due to low voltage/high current operation. The second shock he received was discharging the motor capacitor.

It's not that it could just kill your plants; it could start a fire or possibly kill you

ALSO NOTE: *MOST* of these fans (Fantech, Cap, Vortex etc), the actual motor/impeller assembly is made by EBM, a German motor manufacturer.
You should be able to confirm this by looking at the motor portion of the impeller

 

[jm420]

as far as active air fans go ,the speedster or cap will cause excessive humming ,and fan failure.the active air controller does not /I just ordered one and i'll be back

 

[yesum]

^^mine works great. generic speedster and Hydro Farms active air fan.

 

[jm420]

^^mine works great. generic speedster and Hydro Farms active air fan.

Thats odd mine do not,I have a 4 and 6 active air inline . both of them with the cap control "hum".It is quieter going full speed.Find out in a few days i guess

 

[agoutihead]

We ended up picking up a speedster a couple of weeks ago for $30 locally and it worked perfect. Exactly what we were looking for.

Thanks.

 

[jm420]

the active air is built cheap and a poor design imo, but it works as it should absolutely no humming even at the lowest setting

 

[Hammerhead]

I dont have a hum with the speedster. Im not using it anymore I dont need it. I just checked it on both the 4/6" Active air no hum. I pretty sure Hydrofarm is going to recommend there product over speedster. Does anyone know if Hydrofarm Owns CAP???

 

[BlueBalls]

Does anyone know if Hydrofarm Owns CAP???

They are not listed on Hydrofarms brands page
http://www.hydrofarm.com/our-brands/

Best I can find it's R&M Supply
http://www.randmsupply.com/

 

[Hammerhead]

I sent HFa email about there fans

 

[Hammerhead]

I just got a email from Hydrofarm. There ActiveAir inlines are brushless motors.

 

[samba]

I was told the RIGHT way to slow down a AC motor(fan) is to lower the Hz.
Don't know the name in English, frequency regulator?
But they aren't that cheap...

 

[SMOKE-ONE]

great info!!!

 

[SMOKE-ONE]

what kind of fans are sunleaves "wind tunnels" and what kind of controller is best used to dial them down?Heard they were the most quietest and energy efficient fans on the market.

 

[Chunkypigs]

I've got windtunnels from 4" to 12" and they all work quiet with a variac and sound worse when dimmed with the speedster type dimmers. fans are great but the brackets they are shipped with suck balls...

EDIT: what I'm saying here is that the variac is the right device to slow this type fan and make it run more quietly. The windtunnel fans in the smaller sizes are still way too much like jet engines at full speed for my taste, not the kind of thing you will explain away to someone in the next room. I preach oversize and dial down if you don't what to sound like you are growing.

 

[Chunkypigs]

This is how I mount my windtunnels. I drill out the hole in the plastic bracket and use 4 eyebolts with short rubber bungees that isolate all the vibration eliminating some of the noise factor.

I use s hooks or metal chain to adjust the height of the fan and use just a few inches of flex duct to help decouple the vibrations traveling to the buildings structure. These fans already run quiet compared to the metal ones that are half the cost.

The variac is the real key to quiet and peace of mind in my room. I'm cooling with mother nature at night. this is the small one from the site listed earlier in the thread. I have a larger 10 amp model that I use with a power strip to adjust 6 different fans at the same time. Don't confuse the numbers on the dial for percentages, they read volts. It doesn't hurt to turn them up to 130 overdriving it a bit over your line voltage but not every fan likes going below 70 volts or so. some motors shouldn't be slowed with a variac, they are happy with the speedster type control.

Ventilation is the place to put your money when you are setting up a room IMO... I'm trying to cool with night air and big filters because I don't have the funds for stealth AC right now. Last summer I had an 8" in here because of a mix up with adapters to the filter and things got to sticky for me to get back into the ceiling and swap in the 12" I run 3K bare vert and only had to dial back the ballasts during a couple of heat waves. I think this 12" will keep it plenty cool. By moving ots of air I also manage to cope with high humidity when you get rain crank it to full.

 

[SMOKE-ONE]

What type of controller is best to use with a S&P TD mixed flow?