GRL DNH1-630/30GU Fuse Switch Disconnector 1800V AC Use NH3 fuse link

 Fuse Switch Disconnector DNH1-630/30GU Technical Parameters

GRL DNH1-630/30GU Fuse Switch Disconnector: High-Performance 1800V AC Circuit Protection

1. Overview of the DNH1-GU High-Voltage Series

The GRL DNH1-630/30GU is a specialized fuse-type isolator designed to meet the extreme demands of modern power distribution and motor circuits. As industrial and renewable energy systems push toward higher efficiency, operating voltages have increased, requiring components that can safely manage these elevated levels. This device provides a robust solution for circuit protection where high short-circuit currents are present.

The product is engineered and tested in accordance with the GB/T 14048.3 and IEC 60947-3 standards, ensuring it meets global safety and quality requirements for low-voltage switchgear.

2. Unmatched Voltage and Insulation Performance

The defining characteristic of the DNH1-630/30GU is its ability to operate reliably at voltages far exceeding standard industrial ratings.

• Rated Operating Voltage (Ue): It is certified for AC 1800V, making it a premier choice for high-voltage infrastructure.

• Rated Insulation Voltage (Ui): To prevent dielectric breakdown, the device features a massive insulation capacity of AC 2500V.

• Rated Impulse Withstand Voltage (Uimp): Capable of withstanding transient surges up to 18kV, it offers superior protection against lightning strikes and heavy switching spikes.

Click to download product catalog DNH1 Series Fuse Switch Disconnector

3. Dual-Mode Functionality: Protection and Isolation

The DNH1-630/30GU offers a versatile design that allows it to serve two distinct roles depending on the internal components used:

• Circuit Protection Mode: When equipped with an NH3 fuse link, the device provides automatic overload and short-circuit protection. It features a rated short-circuit current (Iq) of 80kA, allowing it to safely interrupt massive fault energies.

• Line Isolation Mode: If the fuse is replaced with an isolation knife, the device transforms into a dedicated line isolation switch. In this mode, while it no longer provides automatic fault protection, it fulfills all line isolation requirements necessary for safe maintenance procedures.

4. Key Technical Specifications

The DNH1-630/30GU is built for heavy-duty industrial use with the following parameters:

• Frame-rated Operational Current (Ie): 100A.

• Fuse Size Compatibility: Designed specifically for Size 3 (NH3) fuse links.

• Fuse Current Range: Supports fuse rated operating currents from 16A to 100A.

• Usage Category: Classified as AC-20B, suitable for infrequent switching of circuits under no-load conditions.

• Ingress Protection: Offers IP20 protection when closed (On) and IP30 when open (Off), safeguarding personnel from live parts.

5. Installation and Accessories

To maintain peak performance, the DNH1-630/30GU follows strict installation guidelines:

• Mounting: It is a Fixed installation type requiring Vertical installation to ensure optimal arc extinguishing and heat management.

• Torque: For secure electrical connectivity, the terminals support a maximum tightening torque of 28 N.m.

• Expandability: Users can order separate accessories to enhance system intelligence, including auxiliary switches, mechanical fuse monitoring functions, and protective covers.

DNH1 Fuse Switch Disconnector Wiring method

6. Target Applications

The extreme 1800V rating and 80kA breaking capacity make this unit ideal for:

• Renewable energy systems (Utility-scale solar and wind power box transformers).

• Mining operations and heavy-duty motor circuits.

• Advanced industrial power distribution networks requiring high-voltage isolation.

DNH1 Fuse Switch Disconnector Product Showcase

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