Resistive capacitive voltage dividers type RGF (RC divider) are used in high voltage networks within the 72.5-550 kV range. They divide the primary voltage into a standardised, equivalent secondary voltage for meters, measuring and protection devices. The active part of the RC divider consists of capacitive and parallel connected resistive dividing elements. The length of the active part extends along the entire insulator length, which results in linear voltage distribution. Both elements are calibrated to each other and provide accurate transient voltage signals from the high voltage side to the low voltage side. The RC divider enables very high frequency bandwidth; even direct voltages (DC) can be measured. For voltage levels of 300 kV and higher, field distortions are avoided by using a corona ring around the head of the divider. The secondary elements, like adjustment and overvoltage protection components, are located in the terminal box together with the equivalent burden replications. The cover plate of the terminal box can be opened laterally. The connecting sockets for the measuring cables are located on the bottom side of the terminal box. The connection of the secondary output voltage can either be implemented by analogue via a shielded measuring cable or by optionally digital using a fibre optic cable. The RC dividers are factory calibrated and will be delivered with specified measuring cable.
Ferroresonance-free and no saturation effects
- Secondary output can be operated under short-circuit or no-load conditions
- AC and DC accuracy class ±0.1% @fR
- Measurement of harmonics possible up to 1 MHz
- Transient signals can be measured
- Accuracy with harmonics up to 10 kHz of ±0.2
Linear voltage distribution
- The optimised arrangement of the resistive and capacitive elements across the entire insulator length results in excellent voltage distribution.
- The RC divider shows a perfect performance under transient voltage stresses and under high pollution conditions.
- The linear voltage distribution prevents the occurrence of external partial discharges.
- High accuracy at frequencies up to 10kHz
- The specially developed design of the active part with resistive and capacitive
elements guarantees high measurement accuracy and stability up to the 200th
- harmonic of the rated system frequency.
- At the same time, high accuracy and stability in voltage variation (linearity) is
achieved, starting from lower voltages up to the overvoltage factor.
Simple measurement cable connection
- The terminal box has connecting sockets on the bottom side. The measuring Cable can be easily connected without any opening of the terminal box.
- In case additional measuring cable (transmission cable) is needed, the cable can be plugged into the next free available terminal socket. To do this, the prepared burden adaption must be switched off in the terminal box. The divider is still calibrated and ready for operation.