Replacement Diode Value

MonsterBash

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I have a k7000 that has a shorted diode at d22. I looks at the schematics and they don't list a value for the diode.

The markings on it are IN5061GI GP9210.

I have a bunch of old chassis that I'd like to rob the part from. How do I determine another diode that is compatible with this one?

Thanks!
 
I have a k7000 that has a shorted diode at d22. I looks at the schematics and they don't list a value for the diode.

The markings on it are IN5061GI GP9210.

I have a bunch of old chassis that I'd like to rob the part from. How do I determine another diode that is compatible with this one?

Thanks!

The parts list for the K7000 has D22 with a value of 1A 600V rating.
 
That's just one of the rectifier diodes at the very beginning of the power supply.

A 1N5061 is actually a 2A, 600V PIV rectifier, per the datasheets I found.

I wouldn't sub in a 1A part. A 3A part will be fine.

The NTE part discussed has sufficient voltage and current ratings. However, it's a fast-recovery diode; not a feature necessary in a 60Hz rectification circuit (shouldn't hurt, tho).

Personally, I'd probably put a 1N5406 (or 7, or 8). Those are regular ole 3A diodes.
 
So if I'm going on the hunt for one of these locally..

I can go up in Amps but the voltage should stay the same? I've love to get this up and running tonight.

Thanks!!!
 
I can go up in Amps but the voltage should stay the same?

No, it's OK to the have a higher voltage rating, too.

However, if you go too far up in either or both, you'll eventually find that you've got a big-ass diode that may not fit in the space on the PCB.

Be careful applying this information... as it only applies to "regular" diodes. "Zener" diodes are quite different, and their voltage must be matched closely, because of the different way they work and are used.

I checked Radio Shack, and didn't see anything they typically stock with the specs you're looking for. If you want to live on the edge a little, I'd say try a 3A 400V diode, like a 1N5404. Radio Shack carries them (P/N 276-1144). My reasoning: IMHO it's pretty likely that the thing pulls more then 1A on the 120VAC line, esp at start-up. As a result, I don't think it's wise to skimp on the current rating and use a 1A diode. The voltage on the other hand, appears to have some safety factor. The peak inverse volage that is likely to appear across the diode is 2X the peak line voltage, or about 340V. SO, a 400V diode should be fine, just with less over-design/safety-factor. It probably won't last as long as a 600V rated diode, nor handle as much abuse due to a surge etc.... but it should work fine.
 
The parts list does have it as a 1amp 600 volt diode, but I agree that you should up the amp rating to 3 amp since the factory very often would put in components that barely met the needs to save costs.
 
The parts list does have it as a 1amp 600 volt diode, but I agree that you should up the amp rating to 3 amp since the factory very often would put in components that barely met the needs to save costs.

Interesting. I see that, now. I was just looking at the P/N of the component the OP removed.

Looks like a reasonable argument could be made that a 1A diode should be fine, too. That opens up the 1N400x series, also available at Radio Shack.

Personally, though, I like my fuse to be the weakest link. And these have a 2A fuse just upstream of the rectifier diodes... which is why I'm not too keen on 1A diodes in this application.

Anyhow, I just noticed that the OP has spare chassis laying around. Just rob any of the rectifier diodes (D19-D22) off any of them...
 
Interesting. I see that, now. I was just looking at the P/N of the component the OP removed.

Looks like a reasonable argument could be made that a 1A diode should be fine, too. That opens up the 1N400x series, also available at Radio Shack.

Personally, though, I like my fuse to be the weakest link. And these have a 2A fuse just upstream of the rectifier diodes... which is why I'm not too keen on 1A diodes in this application.

Anyhow, I just noticed that the OP has spare chassis laying around. Just rob any of the rectifier diodes (D19-D22) off any of them...

Good point Darren, the weakest point should always be the fuse, but like I said, the manufacturer almost always put in the cheapest components. It's kind of sad sometimes how thinsg get engineered.

You put it very good about how the higher rated components will last longer since they don't get as tortured.
 
I thought I remember reading that you can go up on both with a diode. In any event I FINALLY found a local place that carries a lot of electrical components. It seems if you search for 'Radio Communication' you get better results.

I found a store that had NTE5806, replaced D22 and fixed a couple traces...and finally got HV and neck glow.

Thanks for the help!



No, it's OK to the have a higher voltage rating, too.

However, if you go too far up in either or both, you'll eventually find that you've got a big-ass diode that may not fit in the space on the PCB.

Be careful applying this information... as it only applies to "regular" diodes. "Zener" diodes are quite different, and their voltage must be matched closely, because of the different way they work and are used.

I checked Radio Shack, and didn't see anything they typically stock with the specs you're looking for. If you want to live on the edge a little, I'd say try a 3A 400V diode, like a 1N5404. Radio Shack carries them (P/N 276-1144). My reasoning: IMHO it's pretty likely that the thing pulls more then 1A on the 120VAC line, esp at start-up. As a result, I don't think it's wise to skimp on the current rating and use a 1A diode. The voltage on the other hand, appears to have some safety factor. The peak inverse volage that is likely to appear across the diode is 2X the peak line voltage, or about 340V. SO, a 400V diode should be fine, just with less over-design/safety-factor. It probably won't last as long as a 600V rated diode, nor handle as much abuse due to a surge etc.... but it should work fine.
 
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