Exhaust Fan Capacitor

Do you know why the original capacitor failed? I don't remember the last time I saw a melted capacitor. I've seen exploded, shorted, open and burning capacitors but melted is a new failure mode for me. Maybe you are just being colorful in your description.

First, try to figure out if the fan motor is not damaged, too. It would be best to identify if this capacitor is only used during the start cycle via a centrifugal switch. A shorted centrifugal switch might be a cause of the capacitor failure. Next order the correct value capacitor. Make sure you get both the capacitance and voltage rating correct. If this capacitor is part of a starting circuit, you might get away with using the capacitor twice the designed value as the correct capacitor is in transit but I expect the motor will stall and quickly overheat. (Flames are possible.) If you have two of those 2.2uF capacitors you can put the two in series to achieve a close enough approximation of the one correct capacitor.

Tanx dear, the capacitor is a run capacitor. the voltage rating of old 1.2uf cap was 450v. the 2.2uf cap also has a voltage rating of 450V.

I couldn't find it. Can you post a better link? Thanks.

Hum, must be a hidden difference in yours and mine web access. For the record the full web page address for that lab is

http://www.ee.lamar.edu/gleb/power/Labs/Lab%2011%20-%20Capacitor%20start%20and%20capasitor%20run%20motors.pdf

Kemet has a much more in depth analysis but less derivation than what is in the lab for selecting a run capacitor. In case that embedded link fails too, here is the full Kemet address

http://www.kemet.com/Lists/ProductCatalog/Attachments/158/F9000_GenInfo_MotorCaps.pdf

Neither work for me.

It's you, the link works fine for me.

Try another browser or recheck the link.

I have used FF and Chrome = Same....

Maybe it does not like "!where" I come from, also possible......I cannot see some sites (TV for example) from other countries.....

Can someone please send them to me in an email. Whoever does it, tell me and I will send a PM with a "proper" email address....Thanks.

Given your previous questions on CR4 I would say no, purchase the right sized and rated one to reduce the likelihood you burn down your dwelling.

What was the voltage rating and type of 2.2uF capacitor you were planning on using and how old is it (standard vented electrolytics dry out over time and are a hazard)?

Yes, and have a competent person install it and test the installation to see if the cap was actually defective.

Probably cost less than a new building.

How much $$ for hiring a ""COMPETENT"" (double quotes ) like u?? .may be u will be able to fix all my problems.

I am a student of life always looking for answers from wiser men . so i ask even when i know . pride is what brings u down .

Soooo, your just trolling CR4 by asking questions about low and medium voltage applications, some of which appear to be related to your job, when you already know the answers? Doesn't appear to be the case from where we are sitting they way you are asking.

pride is what brings u down .

That and doing something you appear to not be qualified to do, your boss finding out and you getting fired (unless your a consultant). 230V AC also does a good job of bringing you down, but you should already know that given such previous distribution level questions as this

http://cr4.globalspec.com/thread/79578

Can you see where we are coming from?

You should take pride in yourself and spend more time researching basic questions yourself rather than asking us! We don't know all the answers and we didn't get to where we are in life by asking others first before exhausting all reasonable alternatives for self learning.

There really is no excuse now days with internet access, it's not like you have to buy books to get answers like you used to (unless they are standards-related questions).