HIQUEL GmbH
Page 4
Author:
Peter Reiter
File:
HIQUEL_AppNote_TCL_1_E_R0100.doc
Translator: Markus Rindler
Date:
05.07.2004 12:56
Wiring
Galvanic disconnected AC adapter
Usually the receptacles for the liquids are made of metal and are grounded. In this case you
have to choose a level control with galvanic separated supply. In principle it are level
controls with transformers, recognizable by the AC adapter.
If the receptacle is made of plastic, mounted isolated and not grounded, you can use a level
control without galvanic separated supply. From experience this case can be excluded,
therefore we do not recommend the use of devices without galvanic separated supply.
Earthing
Because of safety reasons you have to ground connection „C“ of the TCL near the liquid
receptacle. The respective rules have to be considered.
Wire
Use a shielded cable for the cabling. The shield itself has to be connected with the level
control at connection „C“. Keep the measurement cabling as short as possible, but cabling
up to 100m do not represent a problem as long as the wiring prevents stray pick-ups into the
measurement cabling. We recommend the positioning of the level control directly next to the
receptacle you want to measure.
For additional improvement use drilled and shielded cables. Use “C“ and „S1“ and „C“ and
„S2“ as drilled lines. The shield must always be connected with “C”.
C
S1
S2
Installation
The measurement of liquid levels takes place with very small current and stream, for this
reason installation near current leading cables has to be avoided. If this is not possible you
have to install additional shields.