The DNH40 series disconnector switch (hereinafter referred to as "the switch") is suitable for industrial power distribution systems with AC 50Hz/60Hz and rated insulation voltage up to 1000V. It is designed for infrequent circuit connection/disconnection and electrical isolation, widely used in construction, power, petroleum, chemical, and automation systems.

Isolator Switches Feature

1、Modular Design

The DNH40 series features a modular structure that can be assembled according to customer requirements.

2、Durable Construction

The switch housing is made of glass fiber-reinforced unsaturated polyester resin, offering excellent flame-retardant properties, dielectric performance, anti-carbonization, and impact resistance.

3、Efficient Operating Mechanism

Equipped with a double spring energy storage mechanism, the switch allows instantaneous release of th spring during operation, ensuring quick connection and disconnection. This mechanism is independent of the operating handle speed, significantly enhancing the switching capabilities.

4、Rotary Contact Structure

The rotary multi-breakpoint contact structure ensures a safe isolation distance, meeting the reliable isolation requirements.

5、Visual Indicator

The position of the moving contact is visible through a window, providing a higher level of safety.

6、Clear Status Indication

The switch features a clear ON/OFF indicator. When in the “O” position, the handle can be locked to prevent accidental operation.

2、Distribution Systems

Used in electrical distribution systems to isolate different sections for maintenance or in case of a fault. Ensures the safety of personnel and equipment.

3、Switchgear and Control Panels

Integral to switchgear and control panels for safe isolation of circuits. Ensures that operators can safely work on electrical panels without the risk of electric shock.

4、Motor Control Centers

Provides isolation for motor control circuits, allowing safe maintenance and operation. Essential in industrial environments where motor control is critical.

5、Photovoltaic Systems

Used in photovoltaic systems to isolate parts of the system for maintenance, ensuring safety and reliability in renewable energy setups.

Key Technical Parameters

Model	DNH40 - 630	DNH40 - 800
Conventional thermal current and rated operational current（A）	630	800
Rated operational voltage (AC - 20/DC - 20)（V）	1000	1000
Rated insulation voltage (Installation category Ⅳ)（Ui V）	1000	1000
Dielectric strength（50Hz 1min kV）	10	10
Rated impulse withstand voltage（Uimp kV）	12	12
Rated operational current (AC - 21A) 690V（A）	630	800
Rated operational current (AC - 22A) 690V（A）	630	800
Rated operational current (AC - 23A) 690V（A）	630	800
Power loss per pole (at rated operational current)（W）	25	40
Rated short - time withstand current ≤ 690V1s（kA）	20	20
Rated short - circuit making capacity ≤ 690V（kA）	80	80
Mechanical life（Oper）	6000	6000
Operating torque (3 - pole)（Nm）	27	27
Terminal screw specification（mm）	M12×40	M12×40
Terminal tightening torque Locking torque（Nm）	50 ~ 75	50 ~ 75

Normal Operating Conditions

Item	Details
Ambient Temperature	Range: - 5℃ to + 40℃, with a 24 - hour average temperature not exceeding + 35℃
Humidity	At maximum temperature (+ 40℃), relative humidity ≤ 50%. At lower temperatures (e.g., + 20℃), higher humidity (up to 90%) is permissible. Special measures must be taken to address occasional condensation caused by temperature fluctuations.
Altitude	≤ 2000m
Pollution Degree	Ⅲ
Installation Category	Ⅳ
Installation Requirements	The switch must be installed in a location free from significant vibration, mechanical shock, or exposure to rain/snow. The installation site must be free of explosive hazardous substances and corrosive gases/dust that could damage metal or insulation.
Note	If the switch is intended for use in ambient temperatures exceeding + 40℃ or below - 5℃, the user must consult the manufacturer.