What farad value is a 4.0K capacitor?

May 14, 2005 16 Replies

I have a ceiling fan speed control with a couple of large capacitors in it and i think at least one of them has failed.



They look like they might be metalized polyester type. They are in the yellow oval cross-section axial packages.



One is marked 8.0K 250V CMC (1-3/4" x 7/8" x 1/2") and the other is marked



4.0K 250V CMC (1-3/4" x 7/8" x 1/2") .

What might 4.0K & 8.0K translate into in terms of Farads?



TIA,



WNM


This is my best guess:

CMC = ceramic multilayer capacitor

8.0 = 8uF = 0,000008F K = tolerance +/-10%

Cheers, Antti OH7GLS

More than likely, they're 8.0µF and 4.0µF, with the 'K' denoting a tolerance of +/- 10%

I would assume they are 4 and 8 microfarad capacitors, 10% tolerance, rated for 250 volt AC operation.

See:

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Read as micofarads (ie uF or F*10^-6). K is likely a tolerance (10%)

(M=20%, J=5%, G=2%, F=1%)

RL

I believe it's very likely that the values are 4uF and 8uF (microfarads). These values are certainly common for ceiling fans and other motors of that size.

If the capacitors are connected to the motor leads by means of the switch, this is most likely accurate. If the capacitors are used in an electronic speed control with numerous other components, these values might not be reasonable.

The 4.0 and 8.0 are uncommon markings (don't generally see the point-zero), but may be common in the country where they were manufactured.

Be aware that these are AC capacitors, and it would not be advisable to use just any capacitors that are marked 4 or 8uF. The voltage rating is usually

250VAC or higher for caps used with these fractional horsepower motors.

Some of the home improvement retail stores and some hardware stores that sell ceiling fans have replacement capacitors.

Cheers WB ................

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I'll second the vote for 4 uF and 8 uF (microfarads). Most ceiling fan capacitors live in this range. See for instance

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and
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.

Matt Roberds

"Warren Massey" schreef in bericht news: snipped-for-privacy@comcast.com...

Usually 4.0K=4kpF=4nF=0.004uF=4000pf. 4.0K and 8.0K are strange values however as they are not in the E12 series.

petrus bitbyter

K will be the tolerance letter. Never ever can remember whether that's 5, 10 or 20 %. Unlikely to be critical.

If they're really big then 4.0 and 8.0 may be the value in uF ( sounds plausible ) . Since it's an ac device check if the cap voltage rating is V rms rather than DC too.

Graham

The K is not the capacitance, it is the tolerance. It is a letter that represents whether the capacitance rating is accurate to 5%, 10% or

20%. I forget if K is 10% or 20%. I think you have a 4 microfarad and a 8 microfarad cap.

Since they are most likely metallized polyester or popypropylene the size and voltage ratings indicate they are 4.0uF and 8.0uF respectively.

They will be similar to units made by ASC Capacitors

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eg.

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K is just the tolerance. You have 4 microfarad and 8 microfarad caps.

"kell" bravely wrote to "All" (15 May 05 20:03:58) --- on the heady topic of "Re: What farad value is a 4.0K capacitor?"

ke> From: "kell" ke> Xref: aeinews sci.electronics.repair:48298

ke> K is just the tolerance. You have 4 microfarad and 8 microfarad caps.

I don't think tolerance is much of an issue with this application. Might it instead be a capacitor type designation? What would be a K type capacitor from that specific manufacturer?

A*s*i*m*o*v

... I worked hard to attach the electrodes to it.

4 microfarads and 8 microfarads. K just refers to tolerance.
4 microfarads and 8 microfarads. K just refers to tolerance.

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