Merlin Gerin (GERIN) Electrical Brand Unit

Module Feature

Merlin Gerin (often abbreviated GERIN) is a famous French electrical brand founded in Grenoble in 1920. It was acquired by Schneider Electric in 1992 and gradually merged into Schneider’s product system after 2009.

Its classic product portfolio includes Multi9 miniature circuit breakers, Compact moulded case circuit breakers, Masterpact air circuit breakers, residual current protectors, contactors and motor protection components. Products comply with IEC, NF and CE standards. Old stock and spare parts are still circulating in the aftermarket for renovation and maintenance projects.

Working principle

Miniature breakers adopt thermal-magnetic trip structure: thermal element responds to overload, magnetic element trips instantly under short-circuit fault. MCCB and ACB use electromagnetic or electronic trip units to protect against overload, short circuit and earth fault. Contactors control frequent switching of power loads.

Onboard components

Bimetallic thermal trip, magnetic coil, arc extinguishing chamber, contact assembly, operating mechanism, plastic / metal enclosure, terminal block.

LED indicators

Most traditional GERIN breakers have no LED. Newer electronic trip versions have local alarm and trip indication LEDs.

Hardware self‑diagnosis

Electronic trip types support self-check of trip unit, ground fault circuit and power supply anomaly; purely thermal-magnetic mechanical breakers have no electronic self-diagnosis function.

Programming software

Electronic trip models support Schneider EcoStruxure Power software for protection setting and test. Traditional mechanical types require no software configuration.

Electrical & Process Parameters

Model:Merlin Gerin (GERIN) Brand:Merlin Gerin (Schneider Electric heritage) Device type:LV / MV power distribution protection components Standard:IEC 60947, NF, CE Function:Overload, short-circuit and earth fault protection for power distribution circuits

Mechanical & Structure

Mounting:DIN rail / panel fixed mounting Protection class:IP20 for front face Housing:Flame retardant plastic or metal frame

Environmental

Operating temperature:-25℃ ~ +60℃ Storage temperature:-40℃ ~ +85℃ Ambient humidity:5~95% non‑condensing Certification:CE, NF, UL optional Status:Discontinued original heritage brand, spare parts available

Installation

Mount on standard DIN rail or panel frame, match rated voltage and current with load. Check arc chamber and contact condition before energizing. Select proper coordination with upstream and downstream protection devices.

Interface

Power input and output terminals, auxiliary contact terminals (optional).

Diagnostic

Breaker trips repeatedly: Overload, downstream short circuit, insulation aging. Cannot close: Internal mechanism jam, residual current trip triggered. Trip slow: Bimetallic element aging, trip unit calibration drift. Auxiliary contact signal abnormal: Auxiliary contact burned or loose wiring.

Product BriefMerlin Gerin (GERIN) classic French power distribution brand, now Schneider heritage, MCB/MCCB/ACB series for building and industrial electrical protection.