Those little postage-stamp-sized voltage testers...

[desmobob]

There's an old saying I lreally like that goes, "A man with one watch knows what time it is. A man with two watches is never sure."

I just received a pair of Ovonic 3S 2200mah LiPos that included one of those little square voltage testers in the box. I think I have at least a half-dozen of those testers around the shop. I happened to have one of mine close by when I found the one in with the Ovonic batteries so I compared their readings.

My advice: if you you're even the slightest bit OCD and value your peace of mind, don't do this.

 

[Glitch]

I got one of those “cell meter 8” things I think it’s a bit more precise

 

[desmobob]

I got one of those “cell meter 8” things I think it’s a bit more precise

That's what you think until you get a second one and compare them...

 

[CreepyQuarryCrawler]

When I use my Hobbywing programmer I keep in my battery storage box to test batteries, I always have this mini heart attack when the first cell reads low compared to the others. Then I remind myself it's powering the device and I calm down lol

 

[RustyUs]

... and? Are we gonna finish the OP, or what? Those numbers represent the facts... er what numbers?

 

[desmobob]

In case anyone missed the point, the post was a humorous reference to OCD behavior and not really about extremely inexpensive voltage testers.

Here are some unsurprisingly slightly different numbers from the cheap, $4 units. I wonder what the readings from three different $250 Fluke meters would be?

Same 3S battery, three different voltage testers:

Tester #1
Cell 1 - 3.80
Cell 2 - 3.80
Cell 3 - 3.86

Tester #2
Cell 1 - 3.77
Cell 2 - 3.84
Cell 3 - 3.69

Tester #3
Cell 1 - 3.79
Cell 2 - 3.80
Cell 3 - 3.81

Greatest deviation was .18V between the readings of the same cell and only .03V and .04V between meters on the other two cells. Not too shabby for four-dollar devices; you might even say impressive!

So, which of the readings are "factual"? When I had only used one meter, I knew the cell voltages. Now, I'm not sure...

 

[Doom!]

Tester #3 seems to be the average between #1 & #2. I'd stick with #3 and disappear the others. Then you can move on to more important things, like why the the same size screws don't always take the same number of turns to tighten.

 

[desmobob]

Tester #3 seems to be the average between #1 & #2. I'd stick with #3 and disappear the others. Then you can move on to more important things, like why the the same size screws don't always take the same number of turns to tighten.

But what if tester #1 or #2 is the one that is truly accurate? What if they're all wrong?

Too funny... I'm not OCD at all. One look at my house or workbench would verify that instantly. I just thought the initial post was fun.

I hope everyone is having a relaxed, satisfying, (and very orderly!) New Year.