HU Series High-Voltage Molded Case Circuit Breaker
Overview
The HU series is a high-voltage molded case circuit breaker (MCCB) for AC networks up to 1140V and 63–800A. With overload and short-circuit instantaneous protection, it distributes power and safeguards lines and power equipment against overload, short-circuit and other faults. Designed for new energy — wind and photovoltaic — applications, it features a novel design, compact size, high breaking capacity and modular internal accessories.
Why Choose Us
✓ High voltage up to 1140V — covers 800/1000/1140V grids in ONE frame family
✓ Up to 50kA rated ultimate short-circuit breaking (Icu), Icu = Ics for reliable fault clearing
✓ Zero arcing distance (0 mm) — safer installation, no arc-chute clearance needed
✓ Modular accessories — shunt release, auxiliary, alarm, combined units share one footprint
✓ Isolation function (symbol —/—) + Category A, meets GB/T 14048.1/.2 (IEC 60947-1/-2)
✓ Wide ambient range -45°C to +70°C, altitude up to 2000m (derating above)
Key Features
| Feature | Description |
| Novel & Compact Design | Newly engineered moulded case with optimised internal layout — smaller footprint than conventional HV MCCBs, easier panel integration. |
| High Breaking Capacity | Rated ultimate short-circuit breaking capacity Icu up to 50kA (AC800V), with Icu = Ics across the range — no capacity derating after fault clearance. |
| Modular Accessories | Internal accessories (shunt release, auxiliary contact, alarm contact and combinations) share a common mounting footprint and are field-configurable. |
| Isolation Function | Built-in isolation function (symbol —/—), compliant with disconnector requirements per GB/T 14048.1 / IEC 60947-1. |
| Zero Arc Distance | Arc-chute design achieves 0 mm arcing distance — improves cabinet layout safety and reduces installation clearance. |
| Wide Environmental Range | Ambient -45°C to +70°C, altitude ≤2000m, pollution degree 3, installation category III — suited to harsh wind/solar sites. |
| Flexible Mounting | Vertical or horizontal mounting; front-plate, rear and plug-in wiring options available. |
| Long Service Life | Mechanical life 20,000 operations, electrical life 1,500 operations — low maintenance over the project lifetime. |
| Scope & Standards | |
| Item | Parameter |
| Rated circuit | AC networks up to 1140V, rated current 63–800A |
| Protection | Overload and short-circuit instantaneous protection |
| Poles | 3P (three-pole) |
| Utilisation category | Category A |
| Isolation | Yes (symbol —/—) |
| Reference ambient | +40°C |
| Standards | GB/T 14048.1 Low-voltage switchgear and controlgear — Part 1: General rules GB/T 14048.2 Low-voltage switchgear and controlgear — Part 2: Circuit-breakers (equivalent to IEC 60947-1 / IEC 60947-2) |
| Normal Service & Installation Conditions | |
| Item | Parameter |
| Altitude | ≤ 2000 m |
| Ambient temperature | -45°C to +70°C |
| Humidity | At 20°C: 90%; at 40°C: ≤50%; higher humidity allowed at lower temperatures (condensation considered) |
| Pollution degree | 3 |
| Installation category | III |
| Mounting magnetic field | ≤ 5 × earth magnetic field in any direction |
| Medium | Non-explosive, no corrosive gas or conductive dust |
| Mounting | Horizontal or vertical; no significant shock/vibration; not in flammable/explosive locations |
| Main Technical Data | |||||
| Parameter | Unit | HU-250 AC800/1000/1140V |
HU-315 AC1140V |
HU-400 AC800/1000/1140V |
HU-630/800 AC800/1000/1140V |
| Rated current In | A | 16,20,25,32,63,80,100,125,140,160,180,200,225,250 | 280,300,315 | 250,315,350,400 | 400,500,630 (HU-630); 630,700,800 (HU-800) |
| Rated operational voltage Ue | V | AC800 | AC1000 | AC1140 | AC1140 | AC800 | AC1000 | AC1140 | AC800 | AC1000 | AC1140 |
| Rated insulation voltage Ui | V | 1150 (AC800/1000); 1250 (AC1140) | 1250 | 1250 | 1250 |
| Rated impulse withstand Uimp | kV | 12 | 12 | 12 | 12 |
| Breaking class | — | H (AC800) | H (AC1140) | — | — |
| Icu (ultimate SC breaking) | kA | 50 | 50 | 20 | 25 | 15 | 20 | 50 | 20 | 15 | 50 | 20 | 15 |
| Ics (service SC breaking) | kA | 35 | 50 | 15 | 20 | 15 | 15 | 37.5 | 15 | 15 | 37.5 | 15 | 15 |
| Isolation | — | Yes | Yes | Yes | Yes |
| Utilisation category | — | A | A | A | A |
| Mechanical life | operations | 20,000 | 20,000 | 20,000 | 20,000 |
| Electrical life | operations | 1,500 | 1,500 | 1,500 | 1,500 |
| Arcing distance | mm | 0 | 0 | 0 | 0 |
| Dimensions (breaker body) | mm | 200×107×138 | 200×107×138 | 257×150×156 | 270×182×158 |
| Dimensions (with accessories) | mm | 280×107×138 | 280×107×138 | 307×150×156 | 320×182×158 |
| Protection Characteristics | |||
| Circuit-breaker In | 1.05In (cold) | 1.3In (hot) | Magnetic trip current |
| 63A | ≥1 h | ≤1 h | 10In ±20% |
| 63 < In ≤ 800A | ≥2 h | ≤2 h | 10In ±20% |
| Installation Dimensions ( mm) | |||||||||||
| Model | A | B | C | D | E | F | G | H | I | J | Mounting holes n-Φd |
| HU-250 | 30 | 30 | 30 | 30 | 188 | 13 | 80 | 280 | 94 | 53 | 2-Φ4.5 |
| HU-315 | 30 | 30 | 30 | 30 | 188 | 13 | 80 | 280 | 94 | 53 | 2-Φ4.5 |
| HU-400 | 30 | 30 | 30 | 30 | 153.5 | 13 | 50 | 307 | 118 | 53 | 2-Φ4.5 |
| HU-630 | 30 | 30 | 30 | 30 | 185 | 13 | 50 | 320 | 118 | 60 | 2-Φ4.5 |
| HU-800 | 30 | 30 | 30 | 30 | 185 | 13 | 50 | 320 | 118 | 60 | 2-Φ4.5 |
Note:At 1000V & 1140V: fit terminal covers on terminals 1/3/5, phase barriers on 2/4/6, and an insulating plate between breaker and metal mounting plate.































