Leviton MS303-DS 30A 600V Three-phase Motor Starter Switch

Product Description

The LEVITON MS303-DS is a three-pole, three-phase AC manual motor starter switch rated for 30 amps at 600 volts. It provides manual ON/OFF switching control of motor loads in industrial and commercial settings. The toggle-style actuator gives clear feedback on switch position, and the nickel-plated triple-combination terminal screws resist corrosion in demanding environments. Licensed electricians and industrial maintenance technicians install this switch as part of motor branch-circuit wiring or as a dedicated motor disconnect. It is classified as industrial grade and fits a standard wall box for straightforward rough-in.

Typical applications include conveyor systems, pumping machines, air compressors, HVAC systems, and other heavy manufacturing equipment that require three-phase motor control. The MS303-DS supports both back and side wiring using terminal clamps or ring terminals, which simplifies installation in tight panel or wall-box conditions. It is well suited for industrial facilities, mechanical rooms, and process environments where a reliable manual motor disconnect is required by code or by design.

Key Features

• 30-amp, 600-volt rating for three-pole, three-phase motor loads
• Suitable for use as a motor disconnect per applicable electrical codes
• Fits standard wall box for straightforward installation
• Accepts back or side wiring with terminal clamps or ring terminals
• Oversized toggle provides clear ON/OFF actuation feedback
• Nickel-plated triple-combination terminal screws for corrosion resistance

Compatibility

Designed for use in three-phase AC motor branch circuits requiring manual ON/OFF control and disconnect capability, including conveyor systems, pumping machines, air compressors, and HVAC equipment.

Installation Notes

Installation should be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and any applicable local codes. De-energize and lock out the circuit before wiring or servicing the switch. Verify that conductor sizing, overcurrent protection, and enclosure ratings are appropriate for the motor load and environment. Do not exceed the 30-amp, 600-volt rating of the device.