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ATS or synchronizing panel: which one does your generator need?

Both panels sit between generators and the load, but they solve different problems.

Automatic transfer switch (ATS)

An ATS chooses between two sources, usually the grid and one generator. It watches the grid, signals the generator to start when the grid fails, transfers the load, and switches back when the grid returns. Use an ATS when you have one generator backing up the grid.

• Sizing: by the full-load current of the larger source at your voltage. At 400 V, roughly 1,000 A for a 500 kW set and 2,000 A for 1,000 kW.
• Poles: 4-pole switches the neutral as well, which most generator installations need.
• Ask for: open or closed transition, time delays, and a manual bypass.

Synchronizing (paralleling) panel

A synchronizing panel lets two or more generators, or a generator and the grid, run connected at the same time. It matches voltage, frequency and phase before closing the breaker, then shares load between the sets.

• Use it when one set is not big enough, when you need N+1 redundancy, or when load varies widely.
• Each set needs a controller with paralleling functions; the generator quotation should say so.
• Paralleling with the grid needs the utility's approval and extra protection.

Quick choice

Standard ATS and synchronizing panels are in our price list.