Blogs

A TT earthing system (Terre-Terre) has the source neutral earthed at the transformer, while the consumer installs their own independent earth electrode on site. The fault loop impedance through that local electrode is too high for overcurrent protective devices to trip reliably — TT systems depend on RCDs for fault disconnection. Three-phase installations use four conductors from the supply, plus a local PE from the site electrode. What Is a TT

Learn what a TN-S earthing system is, how it differs from TN-C-S and TT, and how to configure your SPD correctly for TN-S installations.

SPD wiring diagrams for single-phase, 3-phase and solar systems, covering connection methods for TN-S, TT and IT earthing systems and IEC 61643-11 requirements.

SPD stands for Surge Protective Device. Learn how it protects electrical systems, the 3 IEC-defined types, and key selection parameters.

Type 1, Type 2, and Type 3 SPDs differ by location and surge waveform. Learn which type your project needs and when a Type 1+2 is the right choice.

Learn what a gas discharge tube is, how it works, and how GDTs are used in SPDs. Covers 2-electrode vs 3-electrode types and GDT vs MOV comparison.

Learn what the TN-C-S earthing system is, how it differs from TN-S and TT, and how to configure your SPD correctly for PME installations.

Learn how to select the right surge protection device for solar panel systems — AC/DC placement, Type 1 vs Type 2, key IEC parameters explained.

Protect your outdoor Ethernet from lightning strikes. Discover why an IP68-rated RJ45 Surge Protection Device is essential for Gigabit and PoE networks.

Explore how metal oxide varistors (MOVs) serve as the core of surge protection devices (SPDs), their working principles, applications in power and telecom, and why using certified MOVs is critical for long-term safety and reliability.

Surge events destroy CCTV systems in two ways: a direct hit burns out cameras and NVRs instantly, while repeated low-level transients degrade image sensors and storage drives over months until the system fails without warning. Either way, the fix is the same — surge protective devices (SPDs) installed at both ends of every cable run that connects outdoor cameras to indoor equipment. This guide covers the specific SPD requirements for IP

The choice between 4+0 and 3+1 configuration in a three-phase SPD is not a preference — it is determined by your grounding system. Installing a 4+0 SPD in a TN-C system will expose the N-PE varistor to sustained overvoltage and burn it out. Installing a 3+1 SPD where it is not needed adds cost without benefit. The two configurations protect against different surge paths and are not interchangeable. What do 4+0