In this tutorial we will show you how to properly test for both voltage and current. Voltage is important for determining the charge level on your cells, and to be certain you have things wired correctly after you build a pack.

Current is important to know how smoothly or bind free your car is running. Binding is the number 1 enemy of performance. If your car is binding you will lose power, your batteries will discharge faster and your motor will overheat faster. Current load is the most important measurement you can make when building a car to be sure it runs as smooth as possible.

This tutorial is based on our Mini Meter Pro, but can be done with any comparable MultiMeter. Most meters have DC voltage capability, but not all have Amperage. It also assumes that you are using our Pro Plugs on everything.

Mini Meter Pro
Any Battery or Power Source

To test the voltage of a battery, set your mini meter’s dial to 20 on the DC Voltage Scale. On our Mini Meter this is 3 clicks counterclockwise from off. Connect the black test lead to the “Com” or far left hole. Connect the red test lead to the “VMA” or center hole.

Now you just need to attach the test leads to the cell and you will get a voltage reading. If you see a negative to the left it means that you are backwards, but this is fine as the Mini Meter can measure positive and negative voltage as can most MultiMeters.

You can use the same process to measure a cell that is within a pack. Simply connect the probes the same as before and the meter will only ready the cell you are currently attached to. This way you can check your pack to make sure both cells are at similar voltage. They should be within .5v of each other.

If you have a Pro Plug on your battery pack you just plug it in to check the pack for voltage.

Need to test at the track? No problem, just plug it in.

This is why I love the Mini Meter Pro, it is compact and accurate and very convenient. We have a high end Fluke MultiMeter but grab for the Mini Meter more often.

In this section we will go over measuring current.

Turn the dial on the meter to the Current position. This is clockwise 7 clicks from the off position to where it reads "10A".

Plug the leads in as shown and connect the series harness. You cannot plug it in wrong as it has no polarity.

Now connect it to the car as shown. Again you do not need to worry about polarity, you cannot plug it in wrong.

Now pick the car up off the work surface and give it some throttle. You should get a reading on your current tester.

This is a very smooth car at a 2.04A draw.