Does an Industrial Robot Need Three-Phase Power? It Depends on the Type

Ask a robot vendor what a cell costs and you will get a number for the arm and the controller. What that number almost never includes is whether your building can actually power the thing. For a large share of industrial robots, powering the cell means running a new three-phase circuit, which means an electrician, a panel with spare capacity, and sometimes a service upgrade. For a cobot, it often means plugging into the wall.

That single distinction, single-phase versus three-phase, is one of the most reliable hidden line items in a robot project, and it is almost entirely predictable from the robot type. Across the 106 robots in the Industrial Robotics Hub database that publish an electrical spec, the split is clean enough to budget from before you ever pick a model.

The short answer: cobots and most SCARAs plug into a single-phase wall outlet. Articulated arms, palletizers, welders, and delta robots almost always need a three-phase drop.

Which robot types run on single-phase power?

Power supply sorts by type almost as cleanly as power consumption does, and for the same reason: it is driven by motor size, not by brand. Here is the share of each type in our database that runs on single-phase power (the wall-outlet-friendly case).

Share of each type that runs on single-phase power. Source: analysis of the 106 robots in the Industrial Robotics Hub database that publish a power-supply spec. Delta, welding, and palletizer samples are small but unanimous.

The pattern is stark. On one side, collaborative robots and SCARAs are overwhelmingly single-phase. On the other, articulated arms, delta robots, welders, and palletizers are overwhelmingly three-phase, and the last three categories are unanimous in our data. If your shortlist is cobots, you are almost certainly on single-phase. If it is anything heavy, plan for three-phase.

This lines up with what manufacturers say directly. Universal Robots states that all its cobots are powered by a single-phase 100-240VAC supply and can be plugged into the same outlets that exist in any house, and every UR model in our database matches that spec. Traditional industrial robots, by contrast, typically use three-phase power, often 480V in North American plants.

What the electrical spec actually looks like

The power-supply field on a data sheet is short, but it packs the whole decision. Here are real specs from our database, spanning both bands.

Robot	Type	Payload	Power supply	What you need
Universal Robots UR10e	Cobot	12.5 kg	100-240 V AC	Single-phase, wall outlet
FANUC CRX-10iA	Cobot	10 kg	200-240 V AC, single phase	Single-phase, wall outlet
ABB GoFa CRB 15000-10	Cobot	10 kg	100-230 V AC	Single-phase, wall outlet
Epson T6	SCARA	6 kg	100-240 V AC single phase	Single-phase, wall outlet
Mitsubishi MELFA RH-12FRH	SCARA	12 kg	Single-phase 200 V AC	Single-phase
FANUC CR-35iB	Cobot	35 kg	3-phase 200 V AC	Three-phase (heavy cobot)
FANUC M-20iD/25	Articulated	25 kg	3-phase 200 V AC	Three-phase drop
KUKA KR SCARA R600	SCARA	6 kg	3x AC 400 V	Three-phase (SCARA exception)
Yaskawa AR2010	Welding	12 kg	3-phase 380-480 V AC	Three-phase drop
FANUC M-410iB/700	Palletizer	700 kg	3-phase 200 V AC	Three-phase drop
Yaskawa PL320	Palletizer	320 kg	3-phase 380-480 V AC	Heavy three-phase drop

Power-supply specs as published by the manufacturers and recorded in the Industrial Robotics Hub database. “Wall outlet” assumes a suitably rated and protected dedicated circuit, not literally the nearest socket.

Two things are worth reading off that table. First, three-phase itself splits into two worlds: a 200-230V class common on FANUC and other Japanese-built arms, and a 380-480V class common on European arms and heavy palletizers. A North American plant running 480V and a machine expecting 200V three-phase both need a transformer somewhere, so “three-phase” is not one requirement but a family of them, and it is worth confirming the exact voltage against your building’s supply. Second, the exceptions are real and they bite. The FANUC CR-35iB is a cobot, but at a 35 kg payload it draws enough that it needs three-phase 200V, breaking the “cobots are single-phase” rule. The KUKA KR SCARA R600 is a SCARA that wants three-phase 400V while most SCARAs are happy on single-phase. The type tells you the likely answer; the data sheet confirms it.

Why the phase requirement tracks the robot type

This is physics, not a spec-sheet quirk. A cobot’s joint motors are small, drawing a few hundred watts total, and single-phase delivers that comfortably. A heavy articulated arm, palletizer, or welder has to accelerate and brake hundreds of kilograms through fast, repeated arcs, and that needs kilowatts of torque delivered smoothly. Three-phase power delivers high power with less current per conductor and a steadier torque profile, which is exactly what large servo drives want.

That is why the phase requirement moves in lockstep with power draw. The machines that sip power run single-phase, and the machines that gulp it run three-phase. A cobot around 350W and an articulated arm around 2,000W are not just a factor of six apart on the electricity bill; they are on different sides of the wiring decision too. It also explains why a cobot can even be battery or DC powered in a mobile setup, an option that is meaningless for a 9,500W palletizer.

The part nobody quotes: running the circuit

Here is where this becomes a cost, not a trivia question. If your building already has three-phase distribution at the right voltage with spare breaker capacity near the cell, adding an industrial arm is a modest electrical job. If it does not, the picture changes fast. Running a new three-phase circuit, or worse, bringing three-phase service into a building that only has single-phase, is an electrician’s job with real material and labor cost, and in the upgrade case it can run into the thousands before the robot has moved a single part.

That is the quiet advantage behind the cobot pitch. As covered in our cobot versus industrial robot guide, cobots win on flexibility, floor space, and fenceless deployment. They also win on electrical simplicity: a machine that plugs into an existing single-phase outlet skips the electrician entirely. Manufacturers make the point plainly, noting that in a facility with three-phase distribution you still feed the cobot a single-phase 100-240V line at its input, no special hookup required.

None of this shows up on the arm-and-controller quote. Like the integration and end-of-arm-tooling costs that multiply a robot’s sticker price, the electrical work is part of the true installed cost, and it is one of the few pieces you can estimate early, from the robot type alone, before a single detailed drawing exists.

The practical checklist

Before you commit to a model, answer three questions in order:

1. What phase does the robot need? Read the power-supply spec. Cobot or SCARA, expect single-phase 100-240V. Articulated, palletizer, welding, or delta, expect three-phase, and note whether it wants the 200-230V or the 380-480V class.
2. What does your building have at the cell location? Confirm you have the matching phase and voltage, with a spare breaker of adequate rating within a reasonable cable run. This is a facility question, not a robot question, and it is the one most likely to surprise you.
3. If they do not match, who pays to bridge the gap? A transformer for a voltage mismatch, a new three-phase circuit, or a service upgrade are all real quotes. Get them into the business case before you sign, not after the robot arrives on the dock.

For most cobot projects, this whole checklist collapses to “plug it in.” For most heavy-arm projects, it is a line item worth a phone call to your electrician during the shortlist stage, not after purchase. Either way, the robot type tells you which conversation you are about to have. Filter on the phase you can actually supply, and the electrical spec stops being a surprise.

---

Analysis based on the 106 of 265 robots in the Industrial Robotics Hub database that publish a power-supply specification. Phase classification follows each manufacturer’s stated supply; “single-phase” assumes a properly rated and protected dedicated circuit. Your actual electrical work depends on your building’s existing distribution, so treat the type-level pattern as a planning guide and confirm against the specific model’s data sheet and your local supply.

Frequently asked questions

Does an industrial robot need three-phase power? +

It depends almost entirely on the robot type. Across the 106 robots in the Industrial Robotics Hub database that publish an electrical spec, 32 of 41 traditional articulated arms (78%) need three-phase power, and every palletizer, welding robot, and delta robot in the data runs on three-phase. Collaborative robots are the opposite: 34 of 40 cobots (85%) run on single-phase 100-240V, the same power that comes out of a standard wall outlet. So the honest answer is: a cobot or most SCARAs, usually not; a heavy articulated arm, palletizer, or welder, almost always yes.

Can I plug a cobot into a normal wall outlet? +

In most cases, yes. Universal Robots states that all its cobots run on single-phase 100-240VAC and can be plugged into the same outlets found in any house, and 85% of the cobots in our database follow the same pattern. You still need a properly rated and protected circuit (a dedicated breaker or fuse is good practice), but you do not need an electrician to run a new three-phase service. Watch the exceptions: a few heavy cobots like the FANUC CR-35iB (35 kg payload) require three-phase 200V.

What voltage does an industrial robot use? +

Two bands dominate. Single-phase machines (most cobots and SCARAs) run on roughly 100-240V AC. Three-phase machines split into a 200-230V class (common on FANUC and Japanese-built arms) and a 380-480V class (common on European arms and heavy palletizers, and typical of North American 480V plants). The controller, not the arm, sets the requirement, so it is listed as the power-supply spec on each robot's data sheet.

Why do cobots use single-phase power but industrial robots need three-phase? +

It comes down to motor power. A cobot's small joint motors draw a few hundred watts and are happy on single-phase. A heavy industrial arm, palletizer, or welder accelerates hundreds of kilograms through fast arcs, which needs kilowatts of smoothly delivered torque, and three-phase power delivers that more efficiently with less current per conductor. That is why the power draw and the phase requirement track robot type together: the machines that sip power run single-phase, and the machines that gulp it run three-phase.

Compare these robots

fanuc crx 10ia yaskawa pl320