Standards Development

Scope

This standard specifies and describes the fundamental construction requirements with respect to electrical safety for snow melting photovoltaic (Snow PV) module that is terrestrial, non-concentrating flat plate photovoltaic (PV) module with electric heating sheet adhered to modules or integrated into modules for snow melting. It also describes the testing sequence to verify the construction of such Snow PV module.

The Snow PV module covered by this standard are applicable to, but not limited to, the following circuits:

- Heating circuit with a rated voltage of 250 V AC and either Class I or Class II protection against electric shock - PV circuit with a maximum system voltage of up to 1000 V DC and Class II protection against electric shock

Purpose

The installation rate of PV in snowy regions is not high. One reason is the short annual sunshine duration, but another issue is that once snow accumulates on the roof, it often remains there for an extended period. This obstructs power generation even on subsequent sunny days. Additionally, accumulated snow on the roof can cause various accidents (injuries, deaths) during snowfall and snow removal.

Snowy regions are often areas with declining populations, and as the residents age, there is an increasing need to reduce the labor involved in snow removal. This standard is to address the issues of accidents associated with falling snow and snow removal, as well as the impediment to power generation caused by lingering snow.

Safety related to PV modules is regulated by IEC 61730-1 and IEC 61730-2. On the other hand, safety concerning roof-mounted heaters solely designed for snow melting is covered by IEC 60335-2-83. Until now, there have been no products that integrate both functions, and consequently, no standards have existed for the safety of such integrated products. However, these two functions interact with each other from the standpoint of electrical safety and can impact overall safety. Therefore, there is a growing need for the development of safety standards for products with such combined functions.

A standard structure as used for the technically similar IEC 62109-3 “Safety of power converters for use in photovoltaic power systems - Part 3: Particular requirements for electronic devices in combination with photovoltaic elements” will be considered by the project team.”