I'm actually just charging them to somewhere between 40-50V.=20 There is also a derating of Urms when used at higher frequency. The higher= =20 values start to derate at just above 1kHz. /Ruben >=20 > Thanks. If I may ask, to what max DC voltage do you charge these 250V uni= ts? >=20 > I assume that charging to the rated voltage is safe, but the doubt is the= re. Of > course at ambient temperature. >=20 > Cheers, > Mario >=20 =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D Ruben J=F6nsson AB Liros Electronic Box 9124, 200 39 Malm=F6, Sweden TEL INT +46 40142078 FAX INT +46 40947388 ruben@pp.sbbs.se =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D= =3D=3D=3D=3D=3D --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .