Technical Guides

Maintenance & Replacement Guide Can you replace only the SPD cartridge? When an SPD indicator window turns red, or a remote signal contact sends an alarm, maintenance teams need a…

SPD Bulk Order Certificate Verification Before placing a bulk SPD order, do not check certificates only by looking at the logo. A useful certificate must be traceable, must cover the…

SPD Procurement Guide When buying surge protective devices, do not only ask whether the supplier has CE, TUV, CB or RoHS. The real question is whether those documents match the…

SPD Standard Guide for Buyers Buying an AC SPD? Check IEC 61643-11. Buying a PV/DC SPD for the solar DC side? Check IEC 61643-31. This guide explains the difference between…

Three-Phase SPD Wiring Guide Need a three-phase SPD wiring diagram for a distribution board, control panel, or OEM electrical cabinet? The key point is simple: a three-phase SPD is not…

Ordering SPDs in bulk is not only about price. Before a distributor, OEM buyer, or panel builder places a bulk SPD order, the supplier should confirm the real application, system…

RS485 Surge Protection Guide Not sure how to wire or select an RS485 SPD for a PLC control panel? RS485 communication lines are common in PLC systems, Modbus RTU networks,…

Solar PV DC SPD Selection Not sure whether to choose a 600V, 1000V, or 1500V DC SPD for a solar PV system? One parameter should be checked before the order…

Three-Phase SPD Selection Guide Not sure whether to order a 3P+N SPD or a 4P SPD for a three-phase distribution board? This is a common question for panel builders, electrical…

SPD parameter guide · In rating selection Not sure whether a surge protective device should use 5kA, 10kA or 20kA In? This guide explains what In means, how it differs…