Electrical Test Equipment

Determine Current Draw of AC Electrical Circuit

A circuit breaker is an electrical device used in an electrical panel that monitors and controls the amount of amperes (amps) being sent through the electrical wiring. Circuit breakers come in a variety of sizes. For instance, 10, 15 and 20 amp breakers are used for most power and lighting needs in the typical home. Some appliances and specialty items (washers, dryers, freezers, whirlpools, etc.) will require a larger circuit breaker to handle the electrical load required to run that appliance.

It is important to know the amperage of a circuit breaker so you don't overload the breaker with too many appliances. An overloaded circuit can cause a fire in wiring or generate excessive heat in the circuit box.

1. Find the data plate on the device you are trying to wire.
2. Find the section labeled FLA or LRA, this is the full load. In many instances, the load will be expressed in watts, IE 3800 watts FL.
3. Divide the wattage by the voltage of the circuit, in the USA usually 120 0r 240.
4. The result is the amperage the device draws.
5. Multiply by 1.25, the National Electrical code requires protection at %125.
6. Install circuit breaker to meet that size. Standard branch circuits like lighting require 15 amp. Appliance circuits, IE kitchen, require 20 amp.

• Never replace a 15A or 20A fuse in a fuse box with a 30A fuse
• 30A fuses and breakers are rarely used in a residential circuit box

Electrical Test Equipment Suppliers

• Hoyt Electrical Equipment - http://www.hoytmeter.com/
• Test Equipment Depot - http://www.testequipmentdepot.com/
• Advanced Test Equipment Corporation - http://www.atecorp.com/