NDB3-30, 50, 100 series circuit breakers for equipment (hydraulic electromagnetic type) are applicable to electric systems with the rated current of 100A and the rated voltage not higher than AC480/277V (50/60Hz) and DC125V. The products can be used for infrequent making and breaking as well as overload and short-circuit protection. They are widely used in the computer and peripheral equipment, industrial automation system, telecommunication equipment, universal power supply system, UPS equipment, locomotive, marine electrical system, aerospace, elevator control system and mobile power supply equipment.
◆ With the adoption of the hydraulic magnetic tripping device, it integrates the overload tripping with the short-circuit tripping, which is also known as the electromagnetic circuit breaker;
◆ The tripping performance only depends on the magnetic flux generated by the current flowing through the coil, which is little affected by the ambient temperature change. Therefore, do not consider the reduced capacity due to high temperature;
◆ Cooling time is not required as the circuit breaker is not equipped with thermal elements, which can be re-closed immediately after the fault current disappears;
◆ Viscosity of the hydraulic oil is affected by the temperature change: With large viscosity and long delay time at low temperature, it provides the sufficient additional time during startup of the cold-state equipment. With small viscosity and short delay time at high temperature, the circuit breaker can trip quickly to protect the heating load. Therefore, this "reverse time limit" facilitates the overload protection;