Reference dividers are used for comparative measurements for the calibration of measuring systems. They are designed for the calibration of voltage dividers for AC, DC, full and tail chopped impulse voltages.
The ratio meter type 430 is used for the measurement and check of the transformation ratio of voltage dividers and terminal networks. The instrument measures the real transformation ratio taking into consideration the influence of the surroundings and including the effect of the measuring cable (which is important especially in the case of damped capacitive voltage dividers).
The unit step generator emits recurrent rectangular pulses with rise times of less than 5 ns using a DC source between 60 and 300 V. Its main application is the determination of the transfer characteristics of voltage dividers and shunts according to IEC 60060-3. It can also be used for the measurements of transient over-voltages in networks during switching operations or short-circuits and to determine the voltage distribution across capacitors, resistors, etc. or measurement of their self-inductance.
Before any partial discharge test is conducted with high voltage applied, pulses of known charge values must be fed into the test circuit for calibration of the circuit and for determination of the scale factor of the PD measuring system. Various PD calibrators can be supplied for calibration of standardized PD measuring circuits according to IEC 60270, for RIV PD measurements, or for UHF PD measurements.