The DEHNguard DG M YPV SCI 1000 FM combined with DG MOD STRING 500 / PE 500 is a Type 2 Surge Protective Device (SPD) specifically designed for photovoltaic (PV) DC systems up to 1000 V DC.

Manufactured by DEHN, this surge protection solution is engineered to protect PV string circuits and downstream inverter inputs against transient overvoltages caused by indirect lightning strikes and switching events.

The system integrates DEHN’s SCI (Short Circuit Interrupt) technology, which eliminates the need for additional external backup fuses in many configurations, enhancing system safety and simplifying installation. The FM (Fault Monitoring) remote contact allows real-time status monitoring of the SPD for improved operational control.

With a maximum discharge current of up to 40 kA (8/20 μs), this device provides high discharge capacity and reliable protection for sensitive photovoltaic components.

Designed for DIN rail mounting, the modular construction allows for fast installation and easy maintenance in PV combiner boxes and DC distribution panels.

⚙️ Main Technical Specifications

Manufacturer: DEHN
Product Series: DEHNguard
Model: DG M YPV SCI 1000 FM
Additional Module: DG MOD STRING 500 / PE 500
SPD Type: Type 2 (T2)
Application: Photovoltaic DC systems
Mounting: DIN rail

🔌 Electrical Data

• Maximum system voltage (Ucpv): 1000 V DC

• Maximum discharge current (Imax): 40 kA (8/20 μs)

• Nominal discharge current (In): typically 20 kA (8/20 μs)

• Protection mode: + / – to PE (string protection)

• Integrated SCI technology (internal short-circuit disconnection)

🔔 Additional Features

• Remote signaling contact (FM)

• Pluggable protection modules

• High DC voltage capability (1000 V)

• Optimized for PV string protection

• Compact modular design

🔧 Key Features

✔️ Type 2 SPD for photovoltaic DC systems
✔️ Suitable for installations up to 1000 V DC
✔️ Discharge capacity up to 40 kA
✔️ Integrated SCI technology (no additional backup fuse required in many cases)
✔️ Remote monitoring contact (FM)
✔️ DIN rail mounting
✔️ High-quality German-engineered surge protection

🔗 Ideal Applications

✔️ Photovoltaic combiner boxes
✔️ DC distribution panels
✔️ Rooftop and ground-mounted solar installations
✔️ Commercial and industrial PV systems
✔️ Protection of inverter DC inputs