View Single Post
  #10   Report Post  
Posted to alt.engineering.electrical,sci.electronics.components,sci.electronics.design,sci.electronics.misc,sci.electronics.repair
Spehro Pefhany Spehro Pefhany is offline
external usenet poster
 
Posts: 1,475
Default Where to find thermally-protected radial, wire-wound power resistors?

On Mon, 1 Sep 2014 12:09:39 -0700, the renowned DaveC
wrote:

To summarize:

Wire-wound cermet, radial-lead 22.0 ohm, 10 watt, 5 percent, thermally-fused
@ 185c / 10A.

The original is a labeled SQF10W but I canšt find any reference to this
series. TT Electronics (irctt.com) might be the manufacturer. They have SQM
and CVF series resistors but a search for SQF turns up nada:

irctt.com/file.aspx?product_id=305&file_type=datasheet

Here's images of the remains of the original:

oi60.tinypic.com/vmujo1.jpg

oi62.tinypic.com/wgzqdj.jpg

The internal fuse is clearly labeled 10A and 185c. Not sure if this means
it's only a thermal fuse rated at a maximum of 10A or it's a current fuse
rated at a maximum of 185c or if it's a thermal and current fuse.

Either way it's apparently more than just a resistor.

Help!!

Cheers.


The thermal cutoff looks like a standard type rated at 10A that will
open up permanently at 185°C.

Similar to these:
http://www.koaspeer.com/products/res...-resistors/wf/

or this:
http://industrial.panasonic.com/www-...AOB0000CE8.pdf

or this:
http://www.te.com/commerce/DocumentD...df%7F1879738-1

Given the combination of the (rare in North America) vertical WW
cement resistor and cutoff temperature values this looks like the kind
of part that's easy enough to source in volume but almost impossible
in small quantities.

Also it's a safety device. You might be best off (or at least safest)
approaching the OEM for a repair part. There's clearly something else
major wrong, so it may not be worth fixing.

You could try to cobb something together out of a couple 5W resistors
and a thermal cutoff with some ceramic cement, at your own risk, of
course.


Best regards,
Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog Info for designers: http://www.speff.com