DIY Battery Voltage Tank-o-meter

[ricericerice]

I'm still kinda new around here, hope i posted this in the right section.

For on-the-go battery voltage testing for mech mod users. A cheap, fun, and easy project.

I basically cut open a carto, soldered wires to the postive and negtive terminals inside. I than soldered it to voltage meter. Than stuffed the whole thing into a carto tank.

Make sure you get a carto tank with plastic top and bottom caps, because you have to etch in some grooves (I used a mini-dremel) to let the voltage-meter fit in the tank. I had metal caps and it sucked very bad to make the grooves. Also make sure the carto-tank is tall and wide enough, the dimensions of the meter are listed in the product info.

Link to $2 dollar voltage meter $1.93 0.36" Display 3-Digit 3~30V Voltage Tester for 18650 Battery - red LED at FastTech - Worldwide Free Shipping

The tank-o-meter is accurate when compared to my Fluke multimeter.

Got inspiration from a french e-cig forum and a reddit thread

 

[Punkndrublic]

Very awesome! I'm going to have to try this.

 

[degnr8]

Great idea! Should put this in the modding forum and come see what everybody else is up to

 

[BigBaby]

Way to go, that is a really cool idea and the fit and finish looks great.

 

[ricericerice]

Great idea! Should put this in the modding forum and come see what everybody else is up to

Damn dunno how missed that section.

Sent from my SCH-I545 using Tapatalk 4 Beta

 

[Baditude]

Nice professionally-done project. Finished model looks nice enough to sell. I'd buy one.

 

[Coastal Cowboy]

That's cool, but where'd you get the awsomely awesome bamboo mat?

 

[Bombers]

That is sick! Nicely done man.

 

[HughDaHand]

Nice little mod there. I really like how simple and elegant it is. I think I am gona have to build me one of these.

 

[spider362]

The only problem I can see with it is that it won't measure PPM or PWM voltage correctly. If it's a pure DC voltage it will do just fine.

 

[ricericerice]

The only problem I can see with it is that it won't measure PPM or PWM voltage correctly. If it's a pure DC voltage it will do just fine.

Yep

That's cool, but where'd you get the awsomely awesome bamboo mat?

greatest place on earth, Ikea

 

[ozy.mandias]

Good stuff! Any idea how to tune it so it can measure "under load", i.e. when there's an atty on top of it?

 

[spider362]

When an atty is on top it will automatically measure "under load" voltage unless the output is PPM or PWM.

 

[Dave L]

I'd buy one.

I would too. This is a bit beyond my skill level. Sometimes I wish I'd learned a bit of electrical stuff along the way. That, and learning Spanish.

 

[III BIRDMAN III]

Creative....Well Built....Great Idea

 

[spider362]

I learned the electronics part, although that was over 50 years ago, and other than knowing Ohm's Law it doesn't do me much good now.
Back then it was all vacuum tubes, transistors, resistors, and capacitors. I was long out of school when integrated circuits came along.

The only language offered when I was in school was French, the most useless language to learn in the US as far as I'm concerned. Spanish would have been a lot more reasonable since we have a Spanish speaking country as a neighbor.

 

[ozy.mandias]

When an atty is on top it will automatically measure "under load" voltage unless the output is PPM or PWM.

Sounds good - how do you put an atty on top? From the parts you are showing in the picture, I don't see how to put an atty on top - there is the bottom part of the carto, which obviously goes on the mod, and then positive and negative leads from the carto connector to pins 1+2 of the voltage meter. Do you put a 510 connection in at the top and wire this to other pins? As the photo does not show the top, I'm guessing.

Any hints are much appreciated - I've got all the parts here and maybe will have myself a wee little project over the weekend.

Thanks!

 

[spider362]

Good stuff! Any idea how to tune it so it can measure "under load", i.e. when there's an atty on top of it?

Sounds good - how do you put an atty on top? From the parts you are showing in the picture, I don't see how to put an atty on top - there is the bottom part of the carto, which obviously goes on the mod, and then positive and negative leads from the carto connector to pins 1+2 of the voltage meter. Do you put a 510 connection in at the top and wire this to other pins? As the photo does not show the top, I'm guessing.

Any hints are much appreciated - I've got all the parts here and maybe will have myself a wee little project over the weekend.

Thanks!

I was just following your lead when you made reference to putting an atty on top of it (see first quote), so I thought you already knew how to do it. I didn't realize the voltmeter didn't already have a connector for an atty installed on it.

My point is, a voltmeter will automatically show either a no-load voltage when no load (atty) is attached to it, or the voltage under load when a load (atty) is attached to it.

If you want to be able to measure the voltage under load you will have to figure out how to install a connector on top so you can screw an atty into it.

 

[ozy.mandias]

That's fine - I know how to put another connector on it, I was just wondering how it works connection-wise. I'll try putting the atty connector in the same circuit, so it's both the bottom (mod) connector and the atty on the same terminals of the voltmeter. This way, the difference should be visible.

Thanks for your help, much appreciated!

 

[Dougiestyle]

To wire a connector on top, extent the wires from the voltage display contacts to the connector. Display will read loaded voltage this way. Unscrew atty to display unloaded voltage.

To hide the backside of the circuit, you could install a strip of electrical tap inside the tank barrel to mask the guts. Otherwise, looks good. Will order one of these diplays on my next shopping spree. Thanks for link!