DC isolator switch CNC NV821822 4-pole 32A 1000 VDC

DC isolator switch CNC NV821822 is a 4-pole DIN-rail mounted switch designed for safe isolation of high-voltage DC circuits up to 1000 V and 32 A. The lockable handle and 3 ms arcing time enable reliable disconnection of PV strings or 1–2 MPPT lines for maintenance and emergency shutdowns. The compact unit is suitable for installation in control cabinets, distribution boxes and combiner boxes in solar PV and other DC power distribution systems. It complies with IEC 60947-1, IEC 60947-3, AS5033:2014, NZS5033:2014 and UL508i.

Advantages

The switch provides four-pole isolation with a rated working voltage of DC 1000 V and a rated current of 32 A. A lockable handle secures the switch in the closed position for safety during operation. The device features an arcing time of 3 ms for effective PV string disconnection, flame-retardant and UV-resistant housing, and IP20 protection. Compact dimensions and DIN-rail mounting simplify installation in standard electrical enclosures.

Suitable for

• Solar PV arrays and combiner boxes
• Battery systems and other high-voltage DC installations
• Control cabinets and distribution boxes requiring DC isolation
• Disconnecting 1–2 MPPT lines or multi-conductor DC lines

Key specifications

• Number of contacts: 4
• Rated working voltage (Ue): DC 1000 V
• Insulation voltage (Ui): DC 1500 V
• Rated current (In): 32 A
• Rated impulse voltage (Uimp): 8 kV
• Arcing time: 3 ms
• Mechanical life cycles: 10,000; Electrical life cycles: 3,000
• Connector type: M4; Wire cross-section: max. 4–16 mm²
• Protection class: IP20, V0
• Dimensions: 94.9 × 60.2 × 78.2 mm
• Operating/storage temperature: -40 °C to 85 °C
• Mounting: DIN rail
• Warranty: 24 months

How to use

Mount the CNC NV821822 on a standard DIN rail inside the control cabinet or combiner box. Connect DC conductors to the M4 terminals using appropriate ferrules and cables within the specified 4–16 mm² range. Use the handle to switch the circuit open or closed; the handle can be locked in the closed position for secure operation. Ensure system voltage does not exceed DC 1000 V and follow local electrical codes during installation and commissioning.

Recommendations

Use the isolator for infrequent on/off operations and for isolating up to 1–2 MPPT strings. Verify correct wiring and torque on terminals before energising, and perform maintenance only after the switch has been opened and isolated according to safety procedures.