ECN Forum Forums Code Related Discussion NEC & other Code issues Single Pole Control Switch On 240-v Motor

Installed a 20-a, 240-v, single-phase, dedicated branch circuit for an automotive lift.

The lift-installation instructions required that the lift-motor supply voltage (under load)and current be measured and recorded.

In doing this, we noticed that the lift-motor control switch is only a single-pole device. Other lifts we have worked on have had 2-pole switches.

We were surprised that a nationally-known, ETL-listed lift would use a single-pole switch on a 240-v device. Our local electrical inspector was also surprised when we informed him of what we found.

I'm wondering what others are seeing in this type application. I don't recall ever seeing a 240-v device operated from a single-pole control.

You can use single pole "control" but you still need a 2 pole disconnect.

HVAC equipment uses single pole contactors for 208-240V units & 2 pole ones for 3Ø units all the time.

As the code section quoted in the previous post shows, it's quite code compliant, but means any electrician needs to be on their toes & trust nothing.

Thank you both for your responses.

The circuit in question has of course a 2-pole breaker. The lift was furnished with a pigtail and twist-lock plug, so that serves as the local disconnect.

Most of my experience is in the power industry, and at the utility where I worked, we always used control devices that broke all hot circuit legs.

Breaking all ungrounded legs is actually pretty uncommon when they use solid state switching for controls.