Blogs

How to select and wire a 3-phase surge protection device for TN-S, TT and IT systems. Type 1, 2 and 1+2 options with real parameters per IEC 61643-11.

SPD maintenance guide for industrial sites: IEC 62305 inspection schedules, fault indicator diagnosis, dry-contact monitoring, and replacement criteria.

Overvoltage damages equipment and trips systems. Learn what causes it, how transient and temporary overvoltage differ, and how SPDs protect your installation.

RS485 differential signaling resists noise but not lightning surges. Learn why, where to install RS485 SPDs, and how to select the right device.

DC surge protection devices protect EV chargers, solar, telecom and industrial DC systems. Learn how DC SPDs work, key parameters, and wiring types.

How do you choose an SPD manufacturer you can rely on? Six criteria — certifications, datasheet transparency, OEM capability, and sample readiness — that procurement teams use to qualify suppliers.

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.