This series of products is an improved combined vacuum on-load tap-changer, which is mainly composed of a switching switch and a tap-changer selector (with polarity selector). The main feature is that the tap selector has a semi-closed structure.

The vacuum on-load switch has a switching core of vacuum arc extinguishing, which significantly improves the electrical service life. The switch is mounted on the transformer cover with a head flange and is driven by an electric mechanism mounted on the wall of the transformer box via a drive shaft and a bevel gear box.