Abb st201m-d20 Mcb 1 Pole 20 Amp D Curve UL1077

Product Description

The ABB st201m-d20 is a single-pole miniature circuit breaker (MCB) rated at 20 amps with a D trip curve, built to UL1077 standards for supplementary protection. It belongs to the ST200M series, designed for overcurrent protection in control panels, industrial equipment, and supplementary circuit applications. The D curve characteristic means the breaker tolerates higher inrush currents before tripping, making it suited for loads with significant startup surges such as motors, transformers, and solenoids. Licensed electricians and panel builders are the primary installers of this device.

The st201m-d20 is used in residential, commercial, and light industrial settings where supplementary overcurrent protection is required inside equipment enclosures or control panels. As a UL1077-rated supplementary protector, it is intended for use within equipment rather than as a branch-circuit breaker directly off a service panel. It is well matched to applications where downstream loads draw high inrush currents that would cause nuisance tripping with standard B or C curve breakers.

Key Features

• Single-pole configuration for straightforward installation in space-constrained panels
• 20 amp continuous current rating for mid-range load protection
• D trip curve tolerates high inrush currents, reducing nuisance trips on motor and transformer loads
• UL1077 listed for supplementary circuit protection inside equipment enclosures
• Part of the ST200M series, consistent form factor for multi-breaker panel builds

Compatibility

Designed as a UL1077-listed supplementary protector for use within equipment enclosures and control panels requiring single-pole, 20-amp overcurrent protection with a D trip curve characteristic.

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 panel or equipment before installing or replacing this breaker. As a UL1077 supplementary protector, this device is not a substitute for a branch-circuit breaker and must be applied within the scope of its listing. Verify that conductor sizing and terminal torque requirements match the equipment manufacturer specifications before energizing.