The sensors provide signals for current and voltage measuring as well as voltage reference for electronic protection relays. The measuring functions are obtained by the following physical principals.
Current measurement is effected by using a Rogowski coil. The sensor is short circuit proof and thermically resistant up to a defined persistent current.
Voltage measurement is effected by using an ohmic voltage divider against the operating voltage. The high voltage divider is voltage impulse proof and resistant to high direct voltages (cable testing).
For voltage reference there is a coupling electrode for connecting HR*, MR*, LR* and LRM * systems.
By default, block multi type sensors are equipped with shielded cables and coaxial connector with gilded pins for the signals of current and voltage measurement. In case a current signal is required for current measurement, a cable with current carrying capacity will be used for diversion The coupling electrode for voltage reference is carried on the right side next to the fully shielded secondary connecting terminal.
Commutation of the single measuring ranges is placed under the cover for cable bushing.
The current output (in case of integrated burden) as well as the voltage output can constantly be operated either in an open circuit or short circuited.
*HR = High Resistance *MR = Medium Resistance
*LR = Low Resistance *LRM = Low Resistance Modified