Square D CR306 Magnetic Motor Starter Unit

Module Feature

CR306HH036FA2A belongs to Square D CR306 series NEMA magnetic motor starter.

It combines AC contactor and bimetallic thermal overload relay in one assembly, provides motor start/stop control and overload, phase loss protection. The coil supports specified control voltage, auxiliary contacts for status feedback and interlock logic. NEMA standard frame design, robust silver alloy contacts, arc extinguishing chamber for high inrush current during motor startup. It can be equipped with enclosure options for indoor or outdoor installation, commonly stocked as replacement spare for water treatment, HVAC and general machinery motor control.

Working principle

When control coil is energized, the electromagnetic core pulls in to close main power contacts, three-phase power supplies the motor.

Thermal overload elements heat up with motor operating current. Once overload persists, the bimetallic strip deforms and trips the contactor control circuit to cut off motor power for protection. Auxiliary contacts send RUN/TRIP status signal to PLC or local alarm circuit.

Onboard components

AC electromagnetic coil, silver alloy main contact set, arc chute, bimetal thermal overload heater elements, trip reset mechanism, NO/NC auxiliary contact group, reinforced plastic base and terminal block assembly.

LED indicators

Not applicable for basic unit; matched enclosure or auxiliary module can add RUN and TRIP status indication.

Hardware self‑diagnosis

No built-in electronic self-diagnosis. Overload trip, contact welding and coil failure are judged by control system feedback and visual inspection.

Programming software

Not applicable.

Electrical & Process Parameters

Model:CR306HH036FA2A Brand:Square D (Schneider Electric) Device type:NEMA magnetic motor starter Function:Three-phase motor switching, overload and phase loss protection

Mechanical & Structure

Mounting:35mm DIN rail or base plate bolt mounting Protection class:IP00 open type / optional enclosure up to IP65 Housing:Reinforced thermoplastic industrial housing

Environmental

Operating temperature:-20℃ ~ +60℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing

Certification:UL, CSA, CE, NEMA

Status:Original Square D motor control spare

Installation

Disconnect main power and control power before wiring.

Set overload trip current to match motor rated current, test manual reset and control interlock after wiring.

Interface

3-phase motor power terminal, control coil terminal, auxiliary DI/DO feedback contact terminal.

Diagnostic

Starter fails to pull in: Coil voltage missing, coil burnout or mechanical jamming. Repeated overload trip: Motor overloaded, heater element mismatch or phase imbalance. Contact burnout: Severe inrush, short circuit fault or insufficient contact rating.

Product Brief

Square D CR306HH036FA2A magnetic motor starter, NEMA frame starter spare for pump, fan and conveyor motor control cabinet replacement.