Description
Naming Conventions
*Please refer to the technical manual for GYCM6 dimensional details.
Overview
The GYCM6 economical MCCB is a moulded case circuit breaker series covering rated currents from 10A to 1600A across seven frame sizes (63A to 1600A), designed for AC 50/60Hz circuits with rated operating voltages of 400V/690V and up to 1140V on larger frames. It provides overload, short-circuit and undervoltage protection for power distribution systems and infrequent motor starting, with a rated ultimate short-circuit breaking capacity of 35kA to 100kA. The series complies with IEC 60947-2 and GB/T 14048.2.
Compared with full-featured industrial lines, the GYCM6 focuses on the specifications most projects actually need. It keeps the housing compact, supports reverse wiring, and carries the isolation function symbol, so it can serve as a disconnect point in the circuit.
Working Principle
Inside each breaker, a thermal element responds to sustained overload by bending with heat, while an electromagnetic element trips instantly on short-circuit current. Depending on the release code, units are supplied with electromagnetic release only (code 200) or combined thermal-electromagnetic release (code 300). When a fault occurs, the operating mechanism opens the contacts and the arc is extinguished inside the arc chute, keeping the external arc distance within 50–120mm depending on frame size.
Key Features
- Two breaking levels — L-type (standard) and M-type (high breaking); e.g. 125 frame reaches 35kA (L) or 85kA (M) at AC 400V
- Long service life — up to 8,500 mechanical / 1,500 electrical operations (63 frame)
- Compact body — 3P width from 77mm (63 frame); 2P versions available on 125/250 frames
- Isolation function — suitable for use as an isolating switch per the marked symbol
- Reverse wiring permitted — line and load sides are interchangeable
- High vibration resistance — stable operation in industrial environments
Protection & Accessories
Standard protection covers overload, short circuit and undervoltage. Internal accessories are selected by ordering code:
- Shunt release (SHT) — remote tripping via an external signal
- Undervoltage release (UVT) — trips automatically when supply voltage drops
- Auxiliary contact (AX) — signals breaker ON/OFF status; two sets available on request
- Alarm contact (AL) — signals a fault trip to the monitoring system
Refer to the Release Mode & Accessory Code Reference in the Technical Parameters tab for the full list of ordering codes (200–378) and combination rules.
Installation
Four mounting methods are documented with full dimension drawings:
- Front-panel wiring — standard fixed mounting with M5/M8 terminals
- Back-panel wiring — terminals pass through the mounting plate
- Plug-in mounting — base stays wired; breaker can be replaced without disconnecting cables
- Cabinet door cut-outs — large and small cut-out drawings provided; large cut-out is recommended as the handle surface is curved
Applications
Power distribution panels, building electrical systems, industrial control cabinets, infrequent switching of circuits, and infrequent motor starting in factories, commercial buildings and infrastructure projects. Selective category A applies across the series.
