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SPECTANO 100 User Manual
8
Setup improvements
8.1
Error correction
To eliminate, for example, the stray capacitances and unknown capacitances between the leads of the
used test cell, we recommend performing reference measurements by using a reference material with
a known permittivity (e.g. air). The following error correction is based on the air reference example and
proceeds as follows:
1. Depending on your test cell type, insert either a spacer between the electrodes or adjust
the electrodes with a locking screw so that you can measure the air gap height.
Note:
We recommend using a small spacer (lower than 5 mm) consisting of a material with low
permittivity and especially low losses, for example PTFE or PE. Moreover, the spacer surface must be
flat at all points.
Electrode
Spacer ring
Electrode with guard
Input
Output
Air gap height
Figure 8-1
Adjusting the air gap height by using a spacer
Electrode
Electrode with
guard ring
Figure 8-2
Adjusting the air gap height by using a locking screw
Input
Air gap
height
Output
Height adjustment
with locking screw
