Damped capacitive voltage divider

APPLICATION
The damped capacitive impulse voltage measuring dividers are used to convert the high lightning (LI), chopped lightning (LIC) or switching (SI) impulse voltages from peak voltages up to 4800 kV into a measureable and processable value for a transient recorder or peak voltmeter.
The performance of a capacitance divider is mainly determined by the damping of the high-voltage circuit.
Dividers are designed to fulfill all requirements of IEC standard 60060-2.

GENERAL DESIGN
The high-voltage capacitor is made of single units of solid polypropylene capacitors immersed in oil.
Single capacitor packages are connected in series with the inserted damping resistors. The components are housed in fiber-glass cylinders with metal flanges.
For higher voltages several high-voltage capacitors are connected in series. The low-voltage capacitor is located at the lower end of the capacitor column.
Its compact and coaxial design and its parallel configuration of low-voltage capacitors, provides a very low inductance value and high protection against electrical noise.
The termination resistor for the connection of a 75 Ω measuring cable (triaxial) is included.
The divider has to be connected to a high-impedance measuring system (transient recorder or peak voltmeter ≥ 1 MΩ, ≤ 100 pF).
On the low voltage capacitor branch is located the earthing terminal that is realized with 2 metallic plates to optimize the connection to the earth through copper strips.
The capacitor column, if necessary, is mechanically stabilized with a bracing realized with fiber-glass rods.
At the top of the capacitor column there is the top electrode that as standard is realized with as double toroid.
Between the two toroid of the top electrode is placed the external damping resistor. The divider can be equipped with additional taps for partial operation.
This item allows the optimum adaptation to the relevant test voltage level.
The top electrode is designed and optimized for the rated voltages and wave shapes.


ROUTINE TESTS AND TYPE TEST
A.M.E. certifies the divider performance by different internal test and calibration procedures according to IEC 60060-2. In addition to the internal test report, A.M.E. can provide an official calibration certificate issued by the RSE calibration laboratory
The RSE calibration laboratory is accredited by the Italian Accreditation Body ACCREDIA.

ELECTRICAL MAIN PARAMETERS

03tab Electrical

 *Negative switching impulse. The positive SI requires a special top electrode

 

Scope of supply
Impulse voltage measuring consisting of:

  • High-voltage capacitor
  • Base frame with wheels (air cushions under request)
  • Low-voltage capacitor mounted on base frame
  • Measuring cable (Z = 75 Ω, l = 15÷35 m)
  • Connection point for high voltage and earthing connection
  • Top electrode designed for LI rated voltage
  • Bracing with fiber-glass rods, if necessary
  • Technical Documentation
  • Maintenance user manual
  • Calibration Certificate

 

OVERALL DIMENSIONS AND WEIGHT

03tab2 Overall

 

Options

  • Adaptation to other output low voltages
  • Air cushion instead of wheels
  • Other lengths of measuring cable
  • Special top electrode for SI positive voltage 250/2500
  • ACCREDIA calibration certificate

 

DOWNLOAD THE DATASHEET

images/prodotti/03/03.pdf