DIY: Clamp Meter Lithium Battery Upgrade

If you're interested in converting a clamp meter to use a lithium battery, this article is worth checking out.

The clamp meter used in this project is an off-brand model powered by a 9V supply with three large button batteries. So how do you convert it to lithium battery power? Let's walk through the steps.

First, you'll need a small boost converter module like the one below—it allows you to set various output voltages.

Set the module to 9V, then solder the lithium battery to it and leave a charging port wire ready.

Testing shows the output voltage is stable and accurate.

Next, remove the original battery spring from the clamp meter.

After opening the device, you can apply a bit of petroleum jelly to maintain the rotary switch and circuit board—just a small amount will do.

Once you've completed the circuit board soldering, apply some 704 silicone adhesive to keep everything firmly in place.

Note: The standby power consumption of this boost converter is relatively high—around 0.4mA. So if you just install it as-is, the battery will drain completely in about a dozen days. To solve this, you'll need to add a dedicated power switch.

You can cut a small slot on the side of the clamp meter and drill a hole for the mounting screw.

The switch should fit in the position shown below:

Secure it in place with a self-tapping screw—and you're done!

The original battery compartment can now be repurposed to store the charging cable.

Power it on—everything works perfectly. Project complete!

The End.