Single vs Three Phase
Single vs Three Phase — What Power Do I Actually Need?
Thinking of buying new catering equipment? Don’t plug it in just yet.
One of the most common questions we get isn’t about brands or features — it’s about power. Do you need single phase or three phase? Can you just plug it in, or is a full install required? Let’s break it down in plain English.
What Is the Difference?
Single Phase (1P)
– The same supply most homes and small businesses use.
– Typically offers 230–240V, with a maximum load around 3kW per circuit.
– Many appliances on this supply use a 13A plug — simple, convenient, and install-free.
Three Phase (3P)
– A more powerful supply found in commercial kitchens and industrial settings.
– Delivers 400V across three alternating current phases, ideal for higher-demand kit.
– Requires professional installation and a suitable circuit — often via a 30A, 32A, or higher-rated connection.
Which One Do I Need?
That depends on two key things:
- The equipment’s power draw (kW rating)
– If it’s under 3kW, single phase is likely fine — especially if it’s a countertop unit.
– If it’s over 3kW, or part of a line-up running simultaneously, 3P is usually the safer bet. - What else is running in your kitchen
– Are you running multiple ovens, fridges, fryers, and a dishwasher off one ring?
– Even if individual items are 13A, the total load could trip circuits or reduce performance.
Examples
| Equipment | Typical Supply | Notes |
|---|---|---|
| Commercial microwave | 13A plug | Single phase OK |
| High-power combi oven | 3 phase | Needs dedicated install |
| Undercounter fridge | 13A plug | Low load |
| Conveyor dishwasher | 3 phase | Heavy duty |
| Countertop panini grill | 13A plug | Can be single or dual |
| High-speed oven (e.g. Merrychef) | 13A, 30A or 3P | Varies by model |
What About Food Trucks & Mobile Setups?
If you’re running a mobile catering unit, you might not have access to a standard electrical hookup — and that changes everything.
- LPG (Liquid Petroleum Gas) is often the go-to for fryers, griddles, and ovens in food trucks.
- It’s powerful, portable, and removes the need for heavy electrical supply.
- But it must be installed and tested by a Gas Safe engineer, with regular checks.
- For electrical appliances, you’ll likely be limited to single phase power supplied via:
- Leisure batteries or inverters (limited load)
- Petrol or diesel generators (e.g. 3kVA–6kVA)
- On-site power hookups at events (usually 16A–32A limits)
Many food truck operators mix and match — using LPG for cooking and electric for refrigeration, lighting, and prep equipment.
Always check the total kW draw of your combined kit before buying, and don’t forget that start-up surges can trip smaller generators even if the appliance seems compatible on paper.
Can’t I Just Use an Adapter?
No — and doing so could be dangerous. You can’t “convert” single to three phase safely without a phase converter (which is expensive and usually not recommended for commercial kitchen equipment). Likewise, plugging a 3P machine into a 1P socket won’t work — and could void your warranty.
Final Thought
When in doubt, check the spec sheet — or ask us.
We’re happy to confirm whether a unit is plug-and-play or requires a professional electrician. If you’re planning a kitchen refit or opening a new site, getting your power requirements right from day one can save a lot of downtime and expense.
