UNI-T UT61E 20A Current Measurement Part 2

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joe smith

7 жыл бұрын

More testing with the 20A current shunt in the UT61E along with other mods....

Пікірлер: 21

@JackZimmermann 7 жыл бұрын

Here's hoping you get enough subscribers that you can do like Dave and make your own branded meter. Just send the five page modification list to Brymen and we'll have a Joe Smith Ampzilla Multimeter! ;)

@joesmith-je3tq 7 жыл бұрын

I'll leave the handheld meter designing to the experts. There are already way more subscribers than I would have thought it would reach.

@javierpallalorden 7 жыл бұрын

Impressive work you did there Joe!

@joesmith-je3tq 7 жыл бұрын

The last one is not too bad but lowering the resistance would be the best approach. Hope it at least gives viewers some idea of what would be involved with making a mod like this. That Kasuntest 20A 200mV spec will be a hard one to achieve without adding a gain stage.

@whitevamp1051 7 жыл бұрын

that meter is turning into a beast of a meter. and thanks for all the vids.

@joesmith-je3tq 7 жыл бұрын

No problem, glad you enjoy them. The 61E makes a good candidate for these mods because it is lacking in so many ways. But again, it's not a lot of money.

@SBHSGA 7 жыл бұрын

Thanks, Joe. Very interesting. Happy Friday!

@joesmith-je3tq 7 жыл бұрын

Thanks. Enjoy your weekend.

@Unknownety 7 жыл бұрын

I only have one small remark that I wouldn't mind seeing rectified. Could you make those fans on the power supply a bit less noisy? Maybe place it a bit further away, or under a desk so that the sound doesn't travel straight into the mic. Other then that, your videos are great.

@Gooberslot 7 жыл бұрын

That Cem meter looked to be pretty stable in that first test.

@joesmith-je3tq 7 жыл бұрын

Yes it was. If you go back and look at the videos of the CEM where I have it apart, I believe they are using a 0.005 ohm shunt with a fairly low Watt density. For the $120 Ruby sold it for, it was a great deal.

@codebeard 7 жыл бұрын

Could you use two shunts in parallel which have twice the length of copper?

@joesmith-je3tq 7 жыл бұрын

They are not copper but yes, for the same diameter wire we could double the length and add a second one just like I show in this video.

@zx8401ztv 7 жыл бұрын

Now that larger surface shunt did make it very stable, i bet alone that shunt would improve any ut61e, even if nothing else was done. It wont burn up easy, thats for sure. I see what you mean by the problem of a lower shunt value, not enough vdrop generated, if the micro controller had a digital doubler then the shunt could have been half the value. But hey its much better than original now :-D.

@joesmith-je3tq 7 жыл бұрын

I would have thought they would make the gain settable for the two common shunt sizes but I don't see anything in their documentation for it. With that, we would be looking at 2W for the shunt instead of 4. The fuse we can't do much about. I cut up a better lower Teflon insulator that fits much better. I have made several 15 minute runs at 20A and everything appears fine. The lead free solder I used to install the shunt will flow and the board would be damaged long before the silver solder I used would melt. I made the two ends from brass. It's not great but like you said, it won't burn up easy and I would bench it against that Kasuntest any day with it's tiny little shunt and glass fuse..

@DoRC 7 жыл бұрын

0:10. Im guessing if you're subbed to this channel short videos aren't your thing:):)

@joesmith-je3tq 7 жыл бұрын

It started out as just a simple test, then grew.

@putteification 7 жыл бұрын

That pocket knife needs sharpening. Or at least the tip of it :)

@joesmith-je3tq 7 жыл бұрын

Poor old knife gets used for everything from a screwdriver to a pry bar.

@hardergamer 7 жыл бұрын

That UT61E looks poorly built! no way i would trust it on UK mains.

@joesmith-je3tq 7 жыл бұрын

You may not realize that this meter has been modified a fair amount and does not represent what was supplied by UNI-T. They do offer a GS certified version of this meter.