The Chint NXU-I+II Surge Arrester (Type 1 + Type 2) is a Surge Protective Device (SPD) designed to protect electrical systems from transient overvoltages caused by lightning strikes or switching surges. With discharge capacity up to 40kA, this SPD provides reliable protection for distribution boards, industrial equipment, communication systems, and sensitive electronics.
| Model | NXU |
| Type | Type 1 (Class I/B) + Type 2 (Class II/C) |
| Max Discharge Current (Imax) | 40kA |
| Voltage Protection Level (Up) | ≤1.5kV - ≤2.5kV (depending on model) |
| Standard | IEC 61643-11 / GB 18802.1 |
| Type | Location | Protection Level |
|---|---|---|
| Type 1 (Class I/B) | Main distribution board, at service entrance | Protection against direct lightning strikes |
| Type 2 (Class II/C) | Sub-distribution boards | Protection against indirect strikes and switching surges |
| Type 3 (Class III/D) | Near sensitive equipment | Fine protection for electronics |
Q: Where should I install the SPD?
A: Install Type 1 SPD at the main incoming distribution board (near the main breaker). Type 2 SPD should be installed at sub-distribution boards or downstream panels. For sensitive equipment, add Type 3 protection near the device.
Q: Does SPD need replacement after a surge?
A: The NXU has visual indication (green/red window) showing if protection is active. After major surges, the module may need replacement. Some models have replaceable cartridges for cost-effective maintenance.
Chint NXU-I+II Surge Protector T1 T2 Type 1 and 2 Type B and C Class I and II 40kA 50kA 1P 2P 3P 4P CHNT Surge Arrester
Standard: IEC/EN 61643-11
Protect class: I, II
Rate maximum continuous operational voltage: 275V, 385V
Poles: 1P, 2P, 3P,4P, 1P+N, 3P+N
Protection mode: L-PE, L-N, N-PE
Maximum discharge current(8/20μs)Imax: 50kA
Level of protection Up: 1.5kV for 275V; 1.8kV for 385V
Alternative function: Remote indication contact
Ambient temperature: -40 to +70°C
| Weight | 0.6 kg |
|---|---|
| Dimensions | 22 × 22 × 22 cm |
| SPD Type |
T1 + T2 |
| Rated Voltage (Uc) |
385V |
| Max Discharge Current (Imax) |
40kA |
| Poles |
1P, 2P, 3P, 4P |
Download official engineering datasheets, certified test standards (IEC / UL / CE), wiring diagrams, and dimensional drawings for Chint NXU-I+II Surge Arrester (Type 1 + Type 2).
Pure engineering specifications, tripping curve parameters, and electrical selection guidance for panel builders and system designers.
Verify that the nominal line voltage (AC 230V single-phase or 400V/415V/690V three-phase at 50/60Hz, or DC voltage ratings) falls within the continuous maximum operating limits of the device. Check duty cycle ratings (continuous vs intermittent duty) to ensure thermal stability under full load.
For clean indoor electrical rooms, standard IP20 modular DIN-rail housings are recommended. For outdoor, industrial washdown, or dusty environments, mount components inside weatherproof enclosures rated IP65/IP66 with UV-resistant polycarbonate or powder-coated steel enclosures equipped with compression cable glands.
Ensure proper discrimination by grading current thresholds and tripping time delays: upstream devices should have higher current ratings and intentional short-time delays (Class S), allowing downstream branch MCBs to clear localized faults without blacking out the entire facility.
Components mount on standard symmetrical 35mm DIN rail (EN 60715 / TH35-7.5) or backplate screw fixings. Maintain recommended top/bottom ventilation gaps (typically 30–50mm) to ensure unrestricted air convection, and use standard pin/fork comb busbars to minimize contact resistance and wiring errors.
Select copper or aluminum conductor cross-sections complying with IEC 60364-5-52 current-carrying capacity tables based on continuous load. Always use a calibrated torque screwdriver or torque wrench to tighten terminal screws to the manufacturer-specified torque to prevent hot-spot degradation and loose connections.
