An amp gauge measures the actual amount of electrical current flowing into or out of the battery. The amp gauge needle will move to the (+) when the generator output is recharging the battery. An amp meter does not (as many car owners assume) tell you if the generator charging system is working properly.

What does an Amp meter tell you?

This type of gauge tells you how much and in which direction the electricity is flowing. This sends electricity through the ammeter to the battery and when everything is running smoothly, the ammeter will show a positive (+) reading.

What should Amp gauge read?

Look at the voltmeter while the engine is running. Readings of 14 to 14.5 volts on the gauge when as a good sign. This is typical of a properly operating charging system.

How do you use an Amp gauge?

It is measured in the unit of the Ampere, simply called “Amp,” (A). The most common way to measure current in a circuit is to break the circuit open and insert an “ammeter” in series (in-line) with the circuit so that all electrons flowing through the circuit also have to go through the meter.

How do I read my battery charger?

How to tell if a battery charger is charging. When you first connect and switch on the charger, the needle will move sharply to the right. After a few seconds, you will see the needle gradually move to the left. It will settle at a steady charging point, showing the amps flowing.

What do the numbers mean on a battery charger?

Above the amp scale is the percent charged scale, showing how well charged your battery is. As the battery becomes charged, the needle moves from right to left. This shows a reduction in the number of amps flowing, and an increase in percent charged.