A set of power measurement tools wouldn't be complete without a volt amp meter, especially when you need to be able to determine the maximum power available from a source that is already feeding a load. Residential electrical meters also use a volt-amp type meter, which ignores power factor and ensures that consumers pay for the extra current when they have large appliances that present a reactive load.

You'll find volt amp meter and watt meter products often used in conjunction to determine the power factor of the load. Then a capacitive or inductive load shunt can be calculated, which would cancel the load reactance in order to minimize the current drawn from the source. Volt amp meter information to consider when purchasing include AC and DC voltage ranges, AC current ranges and resistance ranges. When shopping for volt amp meters:

1. Scan a volt amp meter directory of products for hand-held units.

2. Search for a volt amp meter for residential metering.

3. Find a volt amp meter provider carrying panel meters.

Action Steps
The best contacts and resources to help you get it done

Get a hand-held volt amp meter for lower power field applications

For general purpose field use, hand-held volt amp meter products typically handle voltages of up to 600 volts and currents of up to 400 amps.

I recommend: Professional Equipment and Rick-N-Steve each have a volt amp meter list worth considering. Professional Equipment carries a full array of testing and inspection equipment. Rick-N-Steve also carries a number of models.

Purchase a volt amp meter for measuring residential electricity usage

The residential electric meter measures the electricity used. Just as you purchase groceries and gasoline, you buy kilowatt hours (kWh) of electric power. One kWh provides enough energy to generate one hour of light from ten 100-watt lamps. These meters measure volt amps (apparent power) rather than watts (real power). That's why you are charged more if your large appliances present a largely reactive load.

I recommend: Sensus Metering Systems has residential electric meters with measurement accuracy that exceeds ANSI C12.20 (Class 0.2) standards. Master Meter has systems that allow walk-by or drive-by meter wireless meter reading.

Buy a volt amp meter designed to be installed on a panel

In an electrical control panel, a volt amp meter, when required, takes the form of a panel meter. These panel meters are available from a number of suppliers.

I recommend: Cloud EV carries a whole line of electrical panel meters, including volt/amp meters, as does Yokogawa.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  In order to minimize the waste of electricity and paying for more electricity than you actually use, use a volt amp meter to have the largest appliances at your business analyzed for reactive load and shunted to counteract and eliminate the reactance of the load they present to the electric utility company.