IEC TC 37A

IEC SC 37A – Low-Voltage Surge Protective Devices
(Package of IEC 61643 standards)

IEC Subcommittee 37A (IEC SC 37A) develops International Standards for low-voltage surge protective devices (SPDs) used to protect electrical and electronic systems from transient over-voltages.
These standards specify the safety, performance, testing, classification, and installation requirements for SPDs installed in low-voltage power distribution systems.

IEC SC 37A publications cover surge protective devices designed to protect buildings, industrial facilities, telecommunications equipment, renewable energy systems, and sensitive electronic equipment against lightning strikes and switching surges.

List of Standard (IEC TC 37A):

1. IEC 61643-01:2005 Low-voltage surge protective devices – Part 01: General Requirements and test methods
2. IEC 61643-11:2011 Low-voltage surge protective devices – Part 11: Surge protective devices connected to low-voltage power systems – Requirements and test methods
3. IEC 61643-12:2020 Low-voltage surge protective devices – Part 12: Surge protective devices connected to low-voltage power systems – Selection and application principles
4. IEC 61643-21:2000+AMD2–2012 Low voltage surge protective devices – Part 21: Surge protective devices connected to telecommunications and signalling networks – Performance requirements and testing methods
5. IEC 61643-22:2015 Low-voltage surge protective devices – Part 22: Surge protective devices connected to telecommunications and signalling networks – Selection and application principles
6. IEC 61643-31:2018 Low-voltage surge protective devices – Part 31: Requirements and test methods for SPDs for photovoltaic installations
7. IEC 61643-31:2018/COR1:2022 Low-voltage surge protective devices – Part 31: Requirements and test methods for SPDs for photovoltaic installations
8. IEC 61643-32:2017 Low-voltage surge protective devices – Part 32: Surge protective devices connected to the d.c. side of photovoltaic installations – Selection and application principles
9. IEC 61643-32:2017/COR1:2019  Low-voltage surge protective devices – Part 32: Surge protective devices connected to the d.c. side of photovoltaic installations – Selection and application principles