Tangent alert: Sanity check on adding DMM display to a variac?

[sluckey]

I paid $13 at Amazon. I saw them as cheap as $9 but you gotta wait a couple weeks or more for it to come from China. I like Amazon's two day shipping and return policy.

https://www.amazon.com/gp/product/B079J ... UTF8&psc=1

[ChasW]

Y'all got me interested in adding a meter to my old vatiac. So I got the PZEM-061 model that uses a current sense loop rather than a built in sense resistor. The wiring is much more straightforward than the wiring for the PZEM-021. I did the zero mod on mine and it works very well. Here's a short pdf of my unit...

http://sluckeyamps.com/misc/variac.pdf

I see that your 061 is v5 same as the -021. Thanks for heads up on the -061. I may change to that.

[Tony Bones]

Not that Sluckey's work needs my verification, but I bought the same meter as him, wired it the same way as him, and can confirm that it works beautifully right down to 0V.

[ChasW]

Sluckey's version with model -061 does in fact work like a charm. Thanks. I knew I should have bought that one in the place.

[turbofeedus]

Y'all got me interested in adding a meter to my old vatiac. So I got the PZEM-061 model that uses a current sense loop rather than a built in sense resistor. The wiring is much more straightforward than the wiring for the PZEM-021. I did the zero mod on mine and it works very well. Here's a short pdf of my unit...

http://sluckeyamps.com/misc/variac.pdf

Yep, installed last night, works great.

[jam-mill]

Y'all got me interested in adding a meter to my old vatiac. So I got the PZEM-061 model that uses a current sense loop rather than a built in sense resistor. The wiring is much more straightforward than the wiring for the PZEM-021. I did the zero mod on mine and it works very well. Here's a short pdf of my unit...

http://sluckeyamps.com/misc/variac.pdf

Yep, installed last night, works great.

Second that; however, first unit ordered was defective.

[turbofeedus]

Y'all got me interested in adding a meter to my old vatiac. So I got the PZEM-061 model that uses a current sense loop rather than a built in sense resistor. The wiring is much more straightforward than the wiring for the PZEM-021. I did the zero mod on mine and it works very well. Here's a short pdf of my unit...

http://sluckeyamps.com/misc/variac.pdf

Yep, installed last night, works great.

Second that; however, first unit ordered was defective.

What were the symptoms? Just for others who may experience the same thing...

[sluckey]

Yes, please tell.

[jam-mill]

Yep, installed last night, works great.

Second that; however, first unit ordered was defective.

What were the symptoms? Just for others who may experience the same thing...

The first unit booted up when power was applied, showed a normal display for about two (2) seconds and then rebooted; repeat ad nauseum.

EDIT: recommend connecting unit without making any mods first just to ensure it works properly.

[TUBEDUDE]

Mine installed with no issues, measurements agree with other test equipment.

[martin manning]

Looks like you have a different model there, which does PF. Can you post a link to that?

[sluckey]

https://www.amazon.com/gp/product/B07JB ... RZXY79GMH9

This unit uses a PZEM-022 circuit. The "zero" mod shown in this thread can not be applied to this unit. You can see some good pics on banggoods website.

https://www.banggood.com/PZEM-022-Open- ... rehouse=CN

[martin manning]

I've been using a Kill-a-Watt for this purpose, between the Variac and the load. It comes alive at about 40V, which is not too bad. I've read about people opening them up and connecting an external power supply to get them to work down to ~zero volts.

[TUBEDUDE]

SKU 200386 at drokking.com. Here's the data sheet. It was 13 or 14 bux and took 2 weeks from Commieland.

[jam-mill]

Second that; however, first unit ordered was defective.

What were the symptoms? Just for others who may experience the same thing...

The first unit booted up when power was applied, showed a normal display for about two (2) seconds and then rebooted; repeat ad nauseum.

EDIT: recommend connecting unit without making any mods first just to ensure it works properly.

Tested new unit with 25W, 40W, 65W, and 100W light bulbs.

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