Powering New Equipment: Dedicated Circuits, Three-Phase and Disconnects

A new CNC machine, compressor, kiln, walk-in cooler, commercial dishwasher or welder usually arrives with a nameplate and a deadline. Getting power to it safely and on time takes planning: the right voltage and phase, a circuit sized correctly, a disconnect where the code wants it and a building that can carry the added load.

Read the Nameplate and the Manual First

Before the equipment ships, send us its electrical requirements:

• Voltage and phase: 120/240 single-phase, 208 or 240 three-phase, or 480 volt
• Full-load amps, or the minimum circuit ampacity and maximum overcurrent protection on the nameplate
• Motor horsepower and starting method, if it has large motors
• Connection type: cord and plug, or hardwired
• Any control, network or interlock wiring it needs

Single-Phase or Three-Phase?

Most homes and many small commercial spaces have single-phase power. Larger motors and industrial equipment usually need three-phase. If your building has only single-phase service, the options are a utility upgrade to three-phase (which depends on what the utility has nearby), a phase converter, or equipment chosen to run on single-phase. Find out before you buy.

What the Install Involves

• A dedicated circuit sized to the equipment, with conductors and overcurrent protection chosen by the code rules for that equipment (motors have their own sizing rules)
• A disconnecting means, typically within sight of the equipment, so it can be locked out for service
• Conduit and wiring suited to the environment: wet, dusty, corrosive or subject to damage
• Grounding and bonding
• Control wiring, emergency stops and interlocks as required
• Updated panel directories and labels, and arc-flash labels where applicable. See arc-flash labels.

Check Capacity Before It Arrives

A large motor added to a full panel or a service near its limit leads to trips, voltage dips that affect other equipment, and overheating. A quick load check before install tells you whether you need a new feeder, a subpanel or more. See electrical capacity for facilities.

Permits and Downtime

New equipment circuits generally need a permit and inspection. We schedule tie-ins to the panel during off-hours when a shutdown is required, so production keeps running.

Have equipment on the way? Book a visit on our booking page and send us the nameplate; we’ll have power ready when it lands.

Frequently Asked Questions

Can I run three-phase equipment on single-phase power?

Some equipment can run on a phase converter; some can’t, or loses capacity. Check with the manufacturer and with us before buying.

Does new equipment need a dedicated circuit?

Most large equipment does, sized from its nameplate and the code rules for that type of load.

Do I need a disconnect next to the machine?

Usually yes. The code generally requires a disconnecting means within sight of motors and many types of equipment so they can be safely locked out.

How much notice do you need?

As much as possible. Simple hookups can be quick; new feeders, panels or utility changes take longer, especially if equipment has to be ordered.

Why Businesses Call Progress and Heritage

We wire new equipment correctly and on schedule, and check the building can carry it. Our licensed, insured, background-checked electricians serve Lynchburg, Roanoke, Danville, Martinsville and the surrounding counties. See our electrical installations and equipment.