Square D S29387 Circuit Breaker Shunt Trip 208-277V H J L Frame

Product Description

The SQUARE D S29387 is a shunt trip accessory designed for use with H Frame, J Frame, and L Frame circuit breakers. A shunt trip allows remote or automated tripping of a circuit breaker by applying a control voltage to the coil — a critical function in fire alarm systems, emergency power-off circuits, and industrial safety shutdowns. This unit operates on a control voltage of 208 to 277 volts AC, making it compatible with standard commercial and light industrial panel voltages. Licensed electricians install this accessory as part of a compliant branch-circuit or feeder protection scheme where remote tripping capability is required by code or design.

This shunt trip is suited for commercial and light industrial applications where circuit breakers must be tripped remotely from a fire alarm panel, building automation system, or emergency stop station. Compatible frame types include H Frame, J Frame, and L Frame circuit breakers. The accessory mounts internally within the breaker assembly and integrates directly into the existing breaker hardware without requiring external enclosures or additional mounting hardware in most configurations.

Key Features

• Control voltage range of 208 to 277 volts AC for compatibility with commercial panel voltages
• Compatible with H Frame, J Frame, and L Frame circuit breakers
• Enables remote or automated circuit breaker tripping for fire alarm and emergency shutoff applications
• Compact form factor at 4.4 inches long, 2.9 inches wide, and 1.7 inches tall
• Lightweight at 0.29 pounds for straightforward handling during panel work

Compatibility

Designed for use with SQUARE D H Frame, J Frame, and L Frame circuit breakers as stated by the manufacturer.

Installation Notes

Installation of a shunt trip accessory must be performed by a licensed electrician in accordance with NEC requirements for the specific circuit and application. Always de-energize the panel and verify the absence of voltage with an approved meter before beginning work inside any enclosure. The shunt trip coil must be wired to a control circuit that matches the rated control voltage of 208 to 277 volts AC. Consult the breaker manufacturer documentation for the correct mounting position and wiring termination points for this accessory within the target frame type.