Square D KDB3400FT36W PowerPact K MCCB Unit

Module Feature

KDB3400FT36W is a molded case circuit breaker of Square D PowerPact K frame series. It adopts fixed feed-through lug connection design, equipped with electronic trip unit, supports adjustable long-time overload, short-time delay and instantaneous short-circuit protection. Rated frame current 400A, 3-pole, rated voltage 600VAC. Compatible with optional accessories such as auxiliary contact, alarm switch, shunt trip and undervoltage release. Widely stocked as spare for industrial low voltage switchgear, commercial power distribution and heavy motor feeder cabinets.

Working principle

Built-in current transformers collect three-phase load current signals and send data to electronic trip controller. The microprocessor compares measured current with preset protection thresholds. Overload triggers inverse time delay trip; short-time fault triggers delayed trip; severe short-circuit triggers instantaneous trip to isolate fault. Auxiliary contacts feed back breaker ON/OFF and trip status signals to PLC or SCADA system.

Onboard components

CT group, electronic trip unit, main contact assembly, arc quenching chamber, spring operating mechanism, fixed terminal lugs, operation handle and reinforced insulated housing.

LED indicators

Front mechanical markers display ON, OFF and trip status.

Hardware self‑diagnosis

Trip unit monitors CT signal integrity and internal power supply. Protection parameters can be adjusted locally.

Programming software

Schneider power configuration software, used for parameter setting, protection curve editing and fault log review.

Electrical & Process Parameters

Model: KDB3400FT36W Brand: Square D (Schneider Electric) Device type: Molded case circuit breaker Frame rating: 400 A Pole: 3P Rated voltage: 600 VAC Mounting: Fixed feed-through lug Function: Overload, short-circuit protection for low voltage distribution and motor feeders

Mechanical & Structure

Mounting: Panel mounting inside low voltage switchgear Protection class: IP40 front panel Housing: Reinforced insulated plastic enclosure

Environmental

Operating temperature: -25℃ ~ +60℃ Storage temperature: -40℃ ~ +85℃ Ambient humidity: 5~95% non‑condensing

Certification: CE, UL489, CSA Status: Original Square D electrical distribution spare

Installation

Cut off upstream power supply before replacement. Mount breaker on busbar support, tighten incoming and outgoing lug bolts, wire auxiliary or trip accessories if fitted, configure trip parameters, test close, open and protection trip function after commissioning.

Interface

Three-phase main lug terminals, auxiliary/alarm contact terminals, shunt / undervoltage trip terminals.

Diagnostic

Overload trip: Continuous load current exceeds long delay setting. Instant short trip: Short circuit on downstream cable or load. Failed closing: Mechanism locked or trip latch engaged.

Product Brief

KDB3400FT36W breaker, Square D PowerPact K 3P 400A fixed lug MCCB spare for industrial low voltage feeder protection replacement.