I. Standards
What to look for in standards.
Regarding standard practices, the standards are as follows: IEC 61643-31—IEC Webstore (IEC 61643-31:2018 Low-voltage surge protective devices – Part 31: Requirements and test methods for SPDs for photovoltaic installations; these devices are designed to be connected to the DC side of photovoltaic installations rated up to 1,500 V DC; these devices contain at least one non-linear component and are intended to limit surge voltages and divert surge currents; IEC); GB/T 18802.31—China Standards Online Service (GB/T 18802.31-2021 Low-voltage surge protective devices – Part 31: Performance requirements and test methods for SPDs for photovoltaic systems; adopts IEC 61643-31:2018 [IDT/identical adoption]; China Standards Online Service); IEC 61643-11—IECEE (IEC 61643-11:2025 applicable to devices for surge protection against indirect and direct effects of lightning; devices intended to be connected to AC power circuits and equipment rated up to 1,000 V RMS; preferred frequencies 50/60 Hz; IECEE); IEC 61643-01—IEC Webstore (IEC 61643-01:2024 contains the common requirements for all SPDs; applicable to devices for surge protection against indirect and direct effects of lightning or other transient overvoltages; IEC); IEC 61643-32—National Public Service Platform for Standards Information (Low-voltage surge protective devices – Part 32: Selection and application principles for SPDs for photovoltaic systems; identical adoption of IEC…
61643-32:2017 (specifying safety requirements, standard test methods, and ratings for the performance characteristics of surge protective devices on the DC side of photovoltaic power supply systems operating at up to 1500 V DC; National Standard Information Public Service Platform); IEC 62305—IEC Webstore (IEC TR 63227 Lightning and surge voltage protection for PV power supply systems; IEC 62305-1 Protection against lightning – Part 1: General principles; IEC)—Six standards to review: IEC 61643-31, GB/T 18802.31, IEC 61643-11, IEC 61643-01, IEC 61643-32, and IEC 62305; ensure these six standards are properly addressed.
II.
Model Number
What to look for in the model number.
Here is a breakdown of the models: DEHNguard—DEHN (Type 2/Class II SPD per EN/IEC 61643-31; features an integrated PV fuse in the short-circuit path that trips immediately after arc extinction to ensure safe electrical isolation; combines surge, fire, and personal protection in a single device); Type 1—ABB (OVR PV series suitable for PV systems with external lightning protection); VAL-MB—Phoenix Contact (VAL-MB-T1/T2 1500DC-PV Class I/II lightning/surge arrester; suitable for PV systems with a maximum short-circuit current ISCPV of 15kA, compliant with EN 50539-11:2013; standards EN 61643-31:2019/IEC 61643-31:2018); B+C—Prosurge (Class B+C DIN-rail solar PV SPD; TUV-certified Type 1+2 PV DC SPD per IEC/EN 61643-31; 18mm narrow design; pre-wired 3-pole Y-circuit configuration for common-mode and differential-mode protection; lightning current capacity up to 12.5kA 10/350μs); BUD-40—Alibaba (PV DC BUD-40/3; standard EN 61643-31); OVR PV—ABB (OVR PV surge arrester; max discharge current up to 40kA; max continuous operating voltage Uc up to 1500V DC; short-circuit withstand current up to 10kA, requiring no backup protection device). The six models covered are: DEHNguard, Type 1, VAL-MB, B+C, BUD-40, and OVR PV.
III.
Testing
What to look for in testing. Based on testing practices, the focus is on six areas: Class I tests (simulating partial conducted lightning current impulses; recommended for high-exposure locations such as line entry points); TOV (Temporary Overvoltage) testing (following current interruption; DC-specific ratings per IEC 61643-31 for PV installations); VPR (Voltage Protection Rating) (UL 1449 4th Edition for low-voltage systems in North America; covering type designation, SCCR, VPR testing, and thermal testing); 10/350 waveform (lightning current capacity up to 12.5kA 10/350μs); 40kA rating (translating the rating into actual protection for a 1500V string; importance of the pluggable design when a cartridge reaches end-of-life); and thermal disconnection (unique thermal disconnector design). Comprehensive testing covers these six aspects.
IV.
Certification
What to look for in certification.
Regarding certification practices, consider the following: CQC—China Quality Certification Centre (Certification rules CQC33-462112-2022 for PV system DC-side SPDs; applicable to PV SPDs connected to the DC side of PV systems with rated voltages up to 1500V; GB/T 18802.31-2021 “Low-voltage surge protective devices—Part 31: Requirements and test methods for SPDs for photovoltaic installations”; certification mode: type testing + initial factory inspection + post-certification surveillance; CQC); IEC & UL—ABB (IEC and UL certified; ABB); UL 1449—SETsafe (Compliant with UL 1449 / EN 61643-31 standards; rated short-circuit current ISCCR 1000A; operating temperature -40 to 85°C; SETsafe); TUV—Prosurge (TUV certified T1+T2 PV DC SPD per IEC/EN 61643-31 standard; Prosurge); CE & RoHS—Alibaba (Certifications: CE, RoHS, ISO9001, CQC, TUV; housing material: UL94-V0; Alibaba); cRUus—CITEL (Compliant with IEC 61643-11 / EN 61643-11 / UL1449 Ed. 5 / GB/T 18802.11; cRUus certified; CITEL)—Six key certifications to consider: CQC, IEC/UL, UL 1449, TUV, CE/RoHS, and cRUus; ensuring these six certifications are in place.
V.
Applications
What to look for regarding applications.
Based on practical application: DC side—IEC Webstore (SPDs installed on the DC side of photovoltaic installations to protect against induced and direct lightning effects); 1500V—IECEE (IEC 61643-31:2018 devices designed for connection to the DC side of photovoltaic installations rated up to 1,500 V DC); North America—ONCCY (UL 1449 for North American installations—USA/Canada); Large-scale power plants—ABB (suitable for small-scale PV systems and large-scale PV power plants; maximum continuous operating voltage Uc up to 1,500 V DC); Inverters—Trilpeak (DC surge protective devices installed on the PV system’s DC side to clamp transient overvoltages from lightning and switching, protecting inverters, combiner boxes, and monitoring equipment); Protection—LSP (the only correct standard for PV systems is IEC 61643-31; every LSP PV SPD is designed, manufactured, and tested to that standard).
