Full Wave Bridge Rectifier

[jb33]

Hi All,
This is a silicon Full Wave Bridge Rectifier and I shot all 4 diodes with my DMM. I'm getting .488V drop through each diode. I was expecting something much closer to .7V. Does anybody think .488 is a bit low and may warrant replacement? Thank you in advance for your input!

 

[Nigel Goodwin]

No, a faulty rectifier won't have a low voltage drop, it will either be S/C, O/C or reverse leaky - it sounds perfectly fine.

If you put a high current through it, the voltage drop will increase, the tiny current from the meter is making it read much lower than it really is.

 

[jb33]

Thank you Nigel, that makes sense.

 

[aliarifat794]

At lower currents, a diode's forward voltage drop can be less than the nominal 0.7V, so 0.488V may not be abnormal.

 

[Miles Prower]

Hi All,
This is a silicon Full Wave Bridge Rectifier and I shot all 4 diodes with my DMM. I'm getting .488V drop through each diode.

Ptobably Schottkey diodes. A Vf of 0.488V is in the range for Schottkey's.

 

[Diver300]

Ptobably Schottkey diodes. A Vf of 0.488V is in the range for Schottkey's.

I don't think so. 0.488 V is well in the range of large diodes being tested at tiny currents. Schottky diodes would be more like 0.2 - 0.3 V at the current that multimeters test diodes with.

 

[ZipZapOuch]

Ptobably Schottkey diodes. A Vf of 0.488V is in the range for Schottkey's.

Some days I wish we had a "don't like" button instead of just a "like" button.

 

[Nigel Goodwin]

Some days I wish we had a "don't like" button instead of just a "like" button.

So do I

Thinking on, I'm sure there used to be one, it's pointless having one without the other.

It's probably part of this 'woke' crap!.

When we used to have work experience school kids at work, we had to write a report on how well they had done, and they altered the rules so you could only put positive comments. On one particularly useless child we had, I wrote "he turned up on some of the days, and wasn't excessively late on a few of those".