Best guess on resistor wattage rating..

[Blindog]

I've been sorting through some components, and I have several of these precision power resistors that I 'd like to use as screen resistors in a 6L6/EL34 50W.

They are labeled "REON", and under that "HS5" (or 6 hard to tell), 1010 Ohm, 1%

They are about .9 inches long and .24 inches in diameter. Based on what I've seen of similar resistors, I would guess 2-3W. Anyone have any thoughts?

Thanks,

Mark

[IMG768]http://i51.photobucket.com/albums/f359/ ... /1k003.jpg[/img]

[Cliff Schecht]

Should have taken that picture next to a coin for scale. It does look to only be a few Watts though.

[tubeswell]

If you have several, then why not do a blow-up test (for dissipation) on one of them ?

[Cliff Schecht]

Good idea. Being that it's a 1 Ohm resistor, you'll need to either push a few amps at a few volts or scale this according to Ohm's law (P=V*I). What do you have for a power supply?

[gearhead]

As an aside, there was a Reon Resistor Corp based in Yonkers NY.

[Blindog]

Thanks for the input guys. I listed the dimensions in the first post, but here is another pic with a scale. It's about a quarter inch in diameter.

That's a good idea about a blow up test, but you would have to set up some constants and have a way to vary the load voltage, no?

I saw another formula that lists P= E squared / R. Maybe easier to calculate without having to know the current?

By the way, it's a 1K (1010 ohm) resistor, not a 1 ohm.

Mark










[IMG768]http://i51.photobucket.com/albums/f359/ ... 1k2005.jpg[/img][/quote]

[Cliff Schecht]

Yes, you can also use P=V^2/R or P=I^2*R depending on what you are able to measure. If you don't have a power source with a meter on the front then you'll need to either measure the current (measured in series) or voltage at the source (parallel) while doing the test. If you don't have a power source on hand then you may have to rig up an adjustable voltage regulator and use this to shove current into the device. The higher the voltage, the less current you'll need so perhaps try a 12 V or 15 V 1A regulator so you don't end up blowing up the wrong device!

[Blindog]

Yes, you can also use P=V^2/R or P=I^2*R depending on what you are able to measure. If you don't have a power source with a meter on the front then you'll need to either measure the current (measured in series) or voltage at the source (parallel) while doing the test. If you don't have a power source on hand then you may have to rig up an adjustable voltage regulator and use this to shove current into the device. The higher the voltage, the less current you'll need so perhaps try a 12 V or 15 V 1A regulator so you don't end up blowing up the wrong device!

Cool. Well as much as I'd like to build up a test rig and burn up a resistor, maybe it might be easier to figure out the minimum size resistor for my application. I've got 493V on the screens, and I'm not worried so much when I'll be running 6L6's, it's the El34's I'm concerned with. They will draw more current at idle, correct?

Thanks!

Mark

[tubeswell]

FWIW, going by that ruler, the resistor looks like about 5W.

[Blindog]

FWIW, going by that ruler, the resistor looks like about 5W.

I think I'm gonna try 'em out and keep an eye on how hot they get.

Thanks for all the help guys.

Mark

[Phil_S]

FWIW, going by that ruler, the resistor looks like about 5W.

Yeah, surely it's at least 3W.

[Structo]

That'll blow up real goood.
Seriously, I can't remember the brand name but I used to have a handful of those resistors. Can't remember where I got them and where they went......

Probably plenty hefty enough for the screens though.