OMRON J7MN-3R-10 Motor Protection Circuit Breaker (MPCB)

The OMRON J7MN-3R-10 is a 3-pole Motor Protection Circuit Breaker (MPCB) engineered to safeguard electric motors through integrated overload, short-circuit, and phase-loss protection. This thermomagnetic device combines adjustable thermal overload release settings with fixed instantaneous short-circuit protection in a compact DIN rail-mounted package. Rated for 10 A nominal current across 200 V AC to 440 V AC supply ranges, it delivers 4 kW rated operation power at both 230 V and 400 V (AC-3 duty). The unit achieves 100 kA short-circuit breaking capacity at 3 ~ 400 V and operates reliably across -20°C to 60°C ambient conditions.

– Technical Specifications

• Rated Current (Iu): 10 A
• Rated Operating Voltage: 200 V AC to 440 V AC
• Rated Operation Power (AC-3): 4 kW @ 230 V and 400 V
• Short-Circuit Breaking Capacity (Icu): 100 kA @ 3 ~ 400 V
• Thermal Overload Release Setting Range: 6 A to 10 A (adjustable)
• Instantaneous Short-Circuit Release Current: 130 A (fixed)
• Motor Protection Class: Class 10
• Coordination Type: Type “1”
• Switch-off Technique: Thermomagnetic
• Operating Temperature Range: -20°C to 60°C
• IP Rating: IP20

– Key Features

• Three-pole configuration for balanced motor protection
• Adjustable thermal overload release current (6 A–10 A) for application-specific tuning
• Phase-failure detection with automatic disconnection
• Rotary turn-button control for manual operation
• Screw terminal connections for secure field wiring
• Compact 45 mm width (DIN rail optimized)
• Fixed instantaneous short-circuit trip at 130 A

– Typical Applications

• Direct motor protection in industrial AC motor circuits (3~ systems)
• Motor control up to 4 kW capacity at standard industrial voltages
• Manual motor starter service when paired with approved short-circuit protection devices

– Compatibility & Integration

This MPCB can function as a manual motor starter when combined with short-circuit protection. It is compatible with approved fuses or circuit breakers compliant with UL489 or CSA22.2 No. 5, provided sizing follows National Electrical Code (UL) or Canadian Electrical Code (CSA) requirements. No integrated auxiliary switch or under-voltage release is present.