The most important components of the device are:

• Two thyristors in an anti-parallel connection
• A firing circuit, which, depending on the version, triggers a thyristor in the blocking direction at a defined voltage
• A module to detect the voltage at the de-excitation/discharge resistor, detect the current being conducted, identify when the overvoltage protection device triggers and signal the status using binary outputs (applies only to 7VV3003-5...).
• The power connections C, D (copper bars)
• Terminal XEW1 to connect the sensor cable from the de-excitation/discharge resistor (applies only to 7VV3003-5...).
• An "Optional fast de-excitation" module (option G11). The module allows the thyristors to be fired at any time by controlling three fast relays that are independent of one another (applies only to 7VV3003-5...).