Make a DIY mini DC power meter.

My meter stopped working correctly, so I needed a new meter. I already had all the parts laying around and decided to finally make one.
DIY mini DC Power Meter

Benefits of this meter:
-Never needs batteries
-Small and portable
-Cheap and easy to make

The tools I used are:
-Wire strippers – (Amazon)
-Wire cutters – (Amazon)
-Screw drivers – (Amazon)
-Scribe – (Amazon)
-Utility knife – (Amazon)
-Hot glue gun – (Amazon)
-Hot glue sticks – (Amazon)
-Drill – (Amazon)
-Drill bits – (Amazon)
-Soldering gun – (Amazon)
-And some Solder – (Amazon)

And the parts I used for this meter.
-Project box – Hammond 1551G – (Amazon)
-LCD DC voltage meter 2.5-30V – (Amazon)
-Female banana plug connections – (Amazon)
-Meter leads that have banana plugs on one end – (Amazon)

I start by opening the project box.

Its just 2 screws.

And that’s where I got the part number from.

I laid out the parts above the project box to see where everything will fit.

Then used a scribe to mark the positions of everything.

Next was to remove the small tabs built in to hold a circuit board.

I used pliers and wire cutters.

Next is the drill the holes for the banana plugs. I start with a small drill bit.

Small holes made.

Then I drilled 1 small hole on the corner of where the LCD will go.

Sorry about the bad picture!

I place the LCD on again, and use the scribe to mark its position.

The scribe mark.

Now to drill the other 3 holes, so all 4 corners are made.

The next step is to make larger holes for the banana plugs.

Its looking good.

I use a utility knife to cut the square out.

Well that took a while…

The LCD screen has mounting tabs on the sides, I need to cut them off.

That should fit now.

Yep, it’s a great fit.

Back view.

I am reusing old banana jacks, so I un-soldered the leads from it.

I started by installing the jack into the project box.

Then I added the other one, and tightened both down.

That’s a good looking meter, but needs some soldering.

Just 2 wires and I am done soldering!

so far so good…

Now to secure the LCD in place. I used hot glue.

I just put a little hot glue around all sides of the LCD.

Now the glue is dry.

I added a label to show the limits of this meter.

Now to attach the back plate.
mini meter opened up

Again, just 2 screws.
mini meter - screws almost in

And that’s that.
mini meter back view

The new meter is about 2 inches tall!
measure mini meter

Just over 1 inch wide.
measuring mini meter

And only 3/4 of an inch thick!
mini meter measure size

This super tiny meter also never needs batteries changed!
mini dc power meter after building

The power you are measuring will power this meter, super convenient.

You can measure small batteries (over 2.5V DC).
mini dc power meter checking 18650 battery

Or you can check larger batteries, like this dying car battery.

Checking car battery voltage with mini meter

Its super useful on electronic projects.
mini dc power meter testing

An added bonus: If you use 18650 batteries, then you know how much they cost… Brand names are around $10 each battery!!!
Its not hard to take apart a laptop battery and they are full of 18650 batteries
Also note: generic laptop batteries like in the photo have generic batteries, but most brand name laptop batteries have great 18650s!
18650 battery from laptop