What the standard defines
IEC 62109 addresses the safety of power conversion equipment in photovoltaic systems. Its first part covers general requirements — protection against electric shock, against fire, against mechanical hazards, and the marking and documentation a maker must supply. Its second part covers inverters specifically, including the behaviour expected when something upstream or downstream fails.
A maker citing it is stating that the device was assessed against those requirements, usually with a certificate and a test house named.
What it does not promise
It does not grant permission to connect anything to a grid. That is the job of a grid code — a national document that specifies how an inverter must behave when the mains voltage or frequency drifts, and when it must disconnect. An inverter can be safe and still not be certified for a particular country’s grid.
It also says nothing about efficiency, about the quality of maximum power point tracking, or about how long a unit lasts. Those are published separately by the maker or not at all.
What it works with
On this site the standard appears on micro-inverters, hybrid inverters, larger charge controllers and the balcony kits built from them. It is read alongside the grid standards a maker lists, because for anything that plugs into a household socket, both matter and only one of them is about safety.
What people ask before they order
Is IEC 62109 enough to connect an inverter to the grid?
No. Safety of the device and permission to inject into a grid are two different questions: the second is governed by a grid code specific to each country, which the maker lists separately.
Does a charge controller need it?
It applies to power converters in photovoltaic systems, and makers of larger controllers commonly cite it. Whether a particular model falls in scope is stated by the maker.
Last reviewed 16 September 2026