How to read maximum input
The &quot;range code&quot; of your product is &quot;AV5&quot;, it means that your product can handle from 380V to 660V on its 3 inputs (-&gt; tri-phase). The &quot;D&quot; letter also means that you must supply this power analyzer with 230VAC.
UPDATE : When I say :

from 380V to 660V

I mean 380V to 660V AC Three-phased.
Source :
Datasheet