YCM8RT Series

The YCM8RT Series is a family of low-voltage, thermal-magnetic trip moulded case circuit breakers (MCCBs) designed for protection of electrical distribution systems against overload and short-circuit faults. Compliant with IEC 60947-2 / GB 14048.2, the YCM8RT provides adjustable thermal protection and fixed magnetic short-circuit protection, making it suitable for feeder, branch, and motor protection in commercial and industrial installations. The series supports multiple frame sizes and pole configurations, offering reliable interruption performance and long service life.

Technical Specifications (Series)

Model Identification

Specification	Details
Series	YCM8RT
Product Type	Thermal-Magnetic MCCB
Standards	IEC 60947-2 / GB 14048.2
Mounting	Front panel / busbar / chassis
Poles	2P / 3P / 4P

Electrical Ratings

Parameter	Specification
Rated Operational Voltage (Ue)	400 / 415 V AC
Rated Frequency	50 / 60 Hz
Rated Current (In)	63 A – 1250 A (frame dependent)
Breaking Capacity (Icu @ 400 V AC)	25 kA – 50 kA (frame dependent)
Trip Unit	Thermal-Magnetic
Protection Functions	Overload (thermal) & Short-Circuit (magnetic)
Utilization Category	A, typically AC-3

Frame & Rating Range

Frame Rating	Rated Current Range	Typical Poles	Breaking Capacity
YCM8RT-250	63 – 250 A	2P / 3P / 4P	25 kA @ 400 V
YCM8RT-400	100 – 400 A	3P / 4P	35 kA @ 400 V
YCM8RT-630	250 – 630 A	3P / 4P	50 kA @ 400 V
YCM8RT-800	400 – 800 A	3P / 4P	50 kA @ 400 V
YCM8RT-1000	630 – 1000 A	3P / 4P	50 kA @ 400 V
YCM8RT-1250	800 – 1250 A	3P / 4P	50 kA @ 400 V

Protection & Trip Characteristics

Feature	Function
Thermal Overload Protection	Adjustable bimetallic element
Magnetic Short-Circuit Protection	Fixed magnetic trip
Long-Time Delay	Protect against sustained overload
Mechanical Interlock	Prevent unsafe operation
Manual Disconnect	YES

Mechanical & Environmental

Parameter	Details
Mounting	Panel / Busbar / Chassis
Terminal Type	Screw / Bolt Clamp
Mechanical Life	High durability
Operating Temperature	−5 °C to +40 °C
Protection Degree	IP20 (dependent on enclosure)

Typical Pole/Rating Table (Example)

Model Code	Poles	Rated Current (A)	Voltage (V AC)	Breaking Capacity
YCM8RT-250/3P	3P	100 – 250	400 V	25 kA
YCM8RT-400/3P	3P	100 – 400	400 V	35 kA
YCM8RT-630/4P	4P	250 – 630	400 V	50 kA
YCM8RT-800/4P	4P	400 – 800	400 V	50 kA
YCM8RT-1000/4P	4P	630 – 1000	400 V	50 kA
YCM8RT-1250/4P	4P	800 – 1250	400 V	50 kA

Accessories Compatibility

Accessory	Function
Auxiliary Contacts (NO/NC)	Remote position indication
Shunt Trip Release	Remote trip command
Undervoltage Release (UVR)	Trip on under-voltage
Alarm Contact	Fault signal
Mechanical Interlocks	Safe operation interlocks