This International Standard lays down IEC requirements for the design qualification of power conversion equipment (PCE) suitable for long-term operation in terrestrial photovoltaic (PV) systems.
1.1 Equipment included in this scope
This document covers the following items in its scope: electronic power conversion equipment intended for use in terrestrial PV applications. The term PCE refers to equipment and components for electronic power conversion of electric power into another kind of electric power with respect to voltage, current, and frequency. This standard is suitable for PCE for use in both indoor and outdoor climates as defined in IEC 60721-3-3 and IEC 60721-3-4. Such equipment may include, but is not limited to, grid-tied and off-grid DC-to-AC PCEs, DC-to-DC converters, battery charger converters, and battery charge controllers.
This standard covers PCE that is connected to PV arrays that do not nominally exceed a maximum circuit voltage of 1500 V DC. The equipment may also be connected to systems not exceeding 1000 V AC at the AC mains circuits, non-main AC load circuits, and to other DC source or load circuits such as batteries. If particular ancillary parts whereby manufacturers and models are specified in the manual for use with the PCE, then those parts shall be tested with the PCE.
1.2 Equipment for which other requirements may apply This standard has not been written to address characteristics of power sources other than PV systems, such as wind turbines, fuel cells, rotating machine sources, etc. This standard has not been written with the intent of addressing the characteristics of power electronic conversion equipment fully integrated into photovoltaic modules. Separate standards exist or are in development for those types of devices. It is, however, applicable to devices where the manufacturer explicitly specifies the capability of full detachment from and subsequent reattachment to the PV module or if the input and output terminals can be accessed and a specification sheet for the PCE is available. Devices meeting these requirements may be tested as individual samples independent from the PV module.
This standard does not apply to power conversion equipment with integrated (built-in) electrochemical energy storage (e.g. lead acid or lithium-ion). It is, however, applicable to equipment where the manufacturer specifies and permits complete removal of the electrochemical energy storage from the PCE so that stand-alone assessment of the PCE with the storage removed becomes possible.
The object of the test sequences contained herein is to establish a basic level of durability and to show, as far as it is possible within reasonable constraints of cost and time, that the PCE is capable of maintaining this performance after prolonged exposure to the simulated environmental stresses described herein that are based on the intended use conditions specified by the manufacturer. Optional tests contained herein may be selected depending on the intended installation, market, or special environmental conditions that the PCE is anticipated to experience. The categorization imposes differentiated test sequences and test severity levels
reflecting the different requirements of mechanical and electrical 56 components in different environments.
PCE are grouped into categories based on size and installation environment.
The actual life expectancy of components so qualified will depend on their design, their environment, and the conditions under which they are operated. Estimation of a lifetime and wear out is not generally covered by this standard.