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NDB3 Series Hydraulic Electromagnetic Circuit Breaker
Updated:August 01,2020 18:07PM

Rated working voltage (Ue): 80VDC 65VDC 125VAC 120/240VAC 230/240VAC AC250V AC400/415V Standards: IEC 60934 GB/T 17701 UL1077 UL489A KC CRCC; Mechanical/Electrical endurance: 10000/6000 times.
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Description of NDB3 Series

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.



Features of NDB3 Series

  • 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, which can be re-closed immediately after the fault current disappears.
  • The "reverse time limit" facilitates the overload protection.


Technology data

Technology data of NDB3 Series

Tripping timetable(in seconds)

Curves\Current In 135% In 200% In 600% In 1000% In
Z2/J2 No trip 0.3-7 0.1-2 0.08-0.3 0.005-0.1
Z4/J4 No trip 3-70 1-15 0.008-2 0.005-0.35

Tripping timetable(in seconds)

Curve\Current In 1.25In 2In 6In 10In
Z2 No trip 0.5-6.5 0.13-1.2 0.008-0.12 0.004-0.06
Z4 No trip 2-60 0.6-20 0.011-1.3 0.004-0.1
Z6 No trip 45-345 9-60 0.15-5.8 0.005-1.7
J2 No trip 0.7-12 0.13-1.3 0.008-0.13 0.004-0.055
J4 No trip 10-160 2.2-20 0.02-1.3 0.005-0.065
J6 No trip 50-700 10-90 0.1-7 0.006-2


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Questions & Answers for NDB3 Series

  • What is a Hydraulic-magnetic circuit breakers?
    Hydraulic-magnetic circuit breakers. Hydraulic-magnetic breakers protect circuits by cutting power after a time delay. They do not depend on temperature as a tripping mechanism, so they often find use where ambient temperatures are high.
  • Do circuit breakers use electromagnets?
    The magnetic portion of the breaker consists of an iron core with a wire coil around it, forming an electromagnet. Load current passes through the electromagnet coils so the electromagnet responds to short-circuit currents. It may take hydraulic-magnetic breakers 10 msec or more to completely stop current flow.
  • What is a Type B circuit breaker?
    Type B devices are designed to trip at fault currents of 3-5 times rated current (In). For example a 10A device will trip at 30-50A. Type C devices are designed to trip at 5-10 times In (50-100A for a 10A device). Type D devices are designed to trip at 10-20 times In (100-200A for a 10A device).
  • Can a breaker be bad if it keeps tripping?
    The simple answer is that, yes, circuit breakers go bad, so your suspicions may be well-founded. Just like any other essential device in your home (e.g. your water heater, HVAC system, etc.), circuit breakers can quit working properly. That said, don't begin replacing your circuit breaker just yet.
  • What are the 2 types of circuit breakers?
    Standard circuit breakers come in two varieties: single-pole breakers and double-pole breakers. These are simpler breakers that monitor the cadence of electricity as it circulates an indoor space. It keeps track of electricity in electrical wiring systems, appliances and outlets.
  • What is a Type D circuit breaker?
    Type D breakers are generally found in industrial settings. According to the The Electrical Guide, Type D breakers protect devices such as transformers or welding machines — items that can tolerate higher surges of electricity than home appliances.
Tags: CCC UL NDB3-30