Resistor?  Came out of my electric fence charger that was EMF'd by lightning.  Bumbling evaluation with a multimeter shows this the only part that doesn't spec out.  If someone can read the code and spec the component, I'd like to try to get a replacement and try to rehab the $100 charger.

[img]http://www.drhaddix.com/resistor.JPG[/img]

It looks like a capacitor.

Benjamin

I say capacitor as well although it should have a capacitance value somewhere on the body, most likely in microfarads ("micro" being represented by the funny "backwards u" Greek letter - epsilon?)

That there's an MOV.

and you don't need it to run (its just there for spike suppression).

Nope, not a resistor.

*Could* be a disc capacitor from its overall form, but I'm pretty sure this is really an MOV (metal-oxide varistor).

Broadly, MOVs absort voltage spikes.  They are
the key element in common surge protectors.
MOVs "break down" above a certain specified voltage. I believe they are rated in breakdown voltage and joules (energy dissipation).

MOVs *do* age - they become less useful/ protective if exposed to a number of spikes. [This is why surge-protector power strips should be replaced every year or after a known spike... their protective ability becomes vastly reduced.]

Do you have a schematic for the unit? Is this around 120VAC circuitry or on a lower-voltage DC side?  

I suspect this is a 20VAC MOV. If you bought one the same physical disc diameter (different diameters have different joule dissipation) then you might be OK.

However the MOV may have failed because some other component failed ahead of it, causing it to blow - in the case of a power supply, this could save equipment located downstream...

One large mfgr of MOVs I know of is "CKE".

Good luck.


-Bill Wiese
-San Mateo, CA
[email protected]

130 Volt Metal Oxide Varistor (MOV).  Used to suppress transient voltage spikes.  Let me know if you need one.  I've got plenty and can spare a few.

Good picture!!  [;)]





Nuckles.   [smash]

Hey...I was playing with something similar this morning when I was building some simple amps.