Technical Articles

SIKORA CAPACITANCE 2000 for Ultra-High Frequency and Length Resolution As Well As Bare Patch Detection

The device is useful for capacitance measurement with multi-zone technology including FFT and SRL prediction.

CAPACITANCE 2000 Measuring Device

For all LAN, coaxial, telephone or RF cables, the transmission of high frequency, analog or digital signals at minimum loss for the signal amplitude is an essential quality feature. In this context, the measurement of the capacitance during the cable production is of crucial importance. The capacitance determines the impedance of the cable for the specified frequency range and thus, the quality of the cable significantly.

CAPACITANCE 2000 is a capacitance measuring device, which is installed in the cooling trough. It measures online precisely the capacitance of the wire insulation and reliably detects bare patches. Additionally, the system recognizes periodical capacitance changes and determines the Structural Return Loss (SRL).

The system can recognize periodical
capacitance changes and determines
the Structural Return Loss (SRL).

The combination of one short and one long measuring electrode, integrated into one measuring tube (multi-zone technology), is unique. The short measuring electrode with a length of 10 mm identifies periodical capacitance variations with high spatial resolution by means of Fast Fourier Transformation (FFT). From the FFT data, the SRL is determined and gives information about the expected attenuation of the RF signal during data transmission. The long measuring electrode of 125mm measures with high precision the average value of the capacitance.

Precise measuring values for the Capacitance and the Diameter (CD), as they are provided by the mentioned capacitance and diameter measuring devices of the LASER Series 2000/ 6000 respectively CENTERVIEW 8000, are the basis for a perfect CD-Control. The CD-Control assures that the capacitance and the diameter comply with the requirements. This is achieved by an automatic adjustment of the cooling trough and by the control of the line speed. Both influenced quantities are controlled by the processor system ECOCONTROL 6000.

The detection of periodical capacitance variations and the prediction of the Structural Return Loss (FFT and SRL) are available as special features directly on the measuring tube via a diagnosis interface. The processer system ECOCONTROL 6000 offers the display of the FFT/SRL relevant measuring values.