There are three device versions depending on the rated voltage:

The power section of the overvoltage protection device has a P3C connection, 3-pulse fully controlled polygon connection. The feeders to the polygon connection have metal-oxide varistors that absorb overvoltage energy.

Semiconductor fuses included in the devices are accommodated in a fused disconnector with integrated fuse monitoring.

The break-over diodes (BOD) and RC snubbers for the thyristors and varistors are mounted on a printed circuit board as are also the gate series resistors and diodes that transfer the line voltage to the break-over diodes.