DISJONCTEUR DC SUNTREE 2P 800VDC 20A

SUNTREE DC Circuit Breaker 2P – 20A – 800VDC (MCB Type)

This breaker is a miniature circuit breaker (MCB) specifically designed for DC (direct current) circuits. It is essential in photovoltaic systems, solar batteries, and renewable energy systems where DC voltage is high.

General Technical Specifications

Brand: SUNTREE

Common Model: SL72-DC-20 (or equivalent)

Number of Poles: 2P (simultaneously disconnects both positive and negative poles in DC)

Rated Current: 20 A

Rated Voltage: 800 V DC – suitable for PV systems or high-voltage DC systems.

Tripping Curve: Type C (responds to overloads and short circuits with medium sensitivity suitable for DC circuits).

Breaking Capacity: Approx. 6 kA (can interrupt short-circuit currents up to about 6000 A).

Insulation Voltage (Ui): Approx. 1250 V (ensures safe insulation above operating voltage).

Installation: Standard 35 mm DIN rail (easy mounting inside distribution boards).

Protection Degree: IP40 (body), IP20 (terminals) — protection against accidental contact and light dust.

Operating Temperature: Approximately -20°C to +70°C.

Additional Features:

Thermal-magnetic tripping for overload and short-circuit protection.

Non-polarized contacts (connection direction +/− does not matter).

This type of breaker is widely used to protect DC inputs of charge controllers, solar inverters, battery storage systems, and PV strings. Without proper DC protection, persistent arcs in high-voltage circuits may cause serious damage.

What is this breaker used for?

A 2P 20A 800VDC DC circuit breaker:

Protects the circuit against overload (disconnects when current exceeds 20 A).

Rapidly interrupts short circuits even under high DC voltage.

Simultaneously disconnects both positive and negative poles to ensure complete safety — a requirement in DC systems.

It is essential in solar installations because breaking DC current is more difficult than AC; electric arcs may persist if the breaker is not specifically designed for DC applications.

Installation

Disconnect all power before working.

Mount the breaker on a 35 mm DIN rail inside the DC panel.

Connect positive and negative conductors to the appropriate terminals.

Tighten screws to the recommended torque (usually about 2–3 Nm).

Check continuity, polarity, and proper tightening.

Important: Ensure that all DC installations use components certified for direct current. An AC breaker is NOT suitable for high DC voltage applications.