Capacitor help with compressor aftercooler fan

[Teter09]

Hey all!

I'm building an after cooler for my compressor and went out to the garage to start today, and decided I should check that my fan did in fact work. When I hooked it up, it didn't work but on a whim I gave it a spin and low and behold, it started up just fine.

I know this means I need a capacitor, but I'm not that knowledgeable about them. My fan is an ebmpapst Model W2E300-CP02-37. The tag has 8uF 400VDB, which is a capacitor rating I believe, but I'm not sure if the capacitor needs to be exact or not. I'm asking because I can't find anything to match that online, but I did find at amazon something close... http://www.amazon.com/CBB61-Conditioner-Motor-Running-Capacitor/dp/B008AGNLU2/ref=sr_1_fkmr0_1?ie=UTF8&qid=1440892979&sr=8-1-fkmr0&keywords=8uf+400vdb+capacitor

Or if I definitely need the 400 out, then I found this which is 10uf,
http://www.amazon.com/Conditioner-Electric-CBB61-Model-Capacitor/dp/B00E6PXWWI/ref=sr_1_3?ie=UTF8&qid=1440894607&sr=8-3&keywords=8uf+400v+capacitor

Will I be safe to use either of those? Or do I need to keep looking further?

My plan was to wire the fan directly to the pressure switch on top of the compressor motor, since when the motor turns on, I'd want the fan to turn on also.

Thanks for your advice!

 

[pattenp]

Use the 8uf 450V. The higher voltage is OK. Just don't use a lower voltage.

 

[wyliesdiesels]

Use the 8uf 450V. The higher voltage is OK. Just don't use a lower voltage.

The original one is rated 400v isnt it?

 

[chuckcrj]

Pattenp is correct, a higher voltage rating is fine. The important thing is to match the uf or microfarad rating.

 

[wyliesdiesels]

Pattenp is correct, a higher voltage rating is fine. The important thing is to match the uf or microfarad rating.

I know that. I was just pointing out that the manu. Calls for 400v so the OP could go with a 400v 8uf rated cap....

 

[pattenp]

I was saying not to use a voltage lower than the original cap which was 400. I didn't mean lower than 450V.

 

[Teter09]

I know that. I was just pointing out that the original is 400v so the OP could go with a 400v 8uf rated cap....

Original? I think you misunderstood that I read the capacitor needed from the fan tag, there is no capacitor at this point. It was new old stock at a place here in Orlando and was marked down to 5 bucks, so I thought it would make a good after cooler fan since it really moves the air!

First link was 8uF and 450V, 2nd was 10uF and 400V.

Which everyone has said the 8uF 450V is preferred and will work.

Thanks everyone!

 

[wyliesdiesels]

Yeah i quickly read your OP. Whoops....

 

[monkeyspanners]

I know that. I was just pointing out that the manu. Calls for 400v so the OP could go with a 400v 8uf rated cap....

The voltage rating is just the maximum the capacitor should be connected to, not the volts it puts out.

 

[Teter09]

Ok, I think I need some more help because I've obviously made a mistake somewhere.
Fan: EbmPapst Model W2E300-CP02-37.
230V 60Hz
4 Wire.....
Green/Yellow
Black
Blue
Brown

The capacitor you all helped me pick out has arrived (http://www.amazon.com/CBB61-Conditioner-Motor-Running-Capacitor/dp/B008AGNLU2/ref=sr_1_fkmr0_1?ie=UTF8&qid=1440892979&sr=8-1-fkmr0&keywords=8uf%20400vdb%20capacitor&tag=viglink20245-20

It has a 2 wires, Black and Red.

I thought I had this wired up correctly (especially since I was advised by a relative who does HVAC work...but now I'm having doubts),

Green/Yellow wire connected to Ground
Brown Wire connected to neutral
Black wire connected to black wire from capacitor, red from capacitor to one leg of the 240,
Blue wire connected to other leg of 240.

Can someone tell me what I'm doing wrong? Do I need more than 1 capacitor?

Thanks for your help!

 

[chuckcrj]

Post a picture of the motor tag, it should have a diagram. You shouldn't be using a neutral at all for that motor, hopefully you didn't fry it...

Here is the most likely correct way to connect it;

Green / yellow to ground
Brown wire to one side of capacitor (doesn't matter, black or red)
Black wire to one leg of 240
Blue wire and the other capacitor wire to other leg of 240.

May be different, check diagram on motor

 

[Teter09]

Unfortunately there is no diagram on the fan tag.

Here is the tag.
View media item 53124

 

[Teter09]

Thanks Chuckcrj....your advice got me most of the way there. I got a bit of 'go' at first, but it didn't stay on. So I swapped the blue and brown...and away we went!
So in the end it was,

Green/yellow to the ground.
Black to one leg of 240
Blue to one side of capacitor
Brown and other side of capacitor to other leg of 240.

I noticed I can change the airflow direction by swapping the blue and black wires which will come in handy!

Thanks everyone!

 

[chuckcrj]

Sounds good, I did find a pdf for those motors, diagrams are on page 55 and you have it correct.

Here is a link

http://www.ebmpapst.co.za/media/content/downloads_10/catalogs/ebmpapst_-_This_Fan.pdf