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Hydrostatic level probes SGE-25 and SGE-16

 Any measurement range from 1 up to 500 m H

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CapillaryRed (+)Black (–)Lifting handleDiaphragm level

 Integrated internal overvoltage protection circuit  ATEX Intrinsic safety

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Aplisens

Aplisens

SG cable hanger

PP junction box

Application

The SGE-25 hydrostatic level probe is applicable to meas-ure liquid levels in tanks, deep wells or piezometers. The SGE-16 probe is a specialized device designed to measure water levels in narrow diameter piezometers or wells.

Principles of operation, construction

The probe measures liquid levels, basing on a simple relationship between the height of the liquid column and the resulting hydrostatic pressure. The pressure meas-urement is carried out on the level of the separating dia-phragm of the immersed probe and is related to atmos-pheric pressure through a capillary in the cable. The active sensing element is a piezoresistant silicon sensor separated from the medium by an isolating dia-phragm. The electronic amplifier, which works in combina-tion with the sensor, and is meant to standardize the sig-nal, is additionally equipped with an overvoltage protection circuit, which protects the probe from damage caused by induced interference from atmospheric discharges or from associated heavy current engineering appliances.

Installation, method of use

When lowered to the reference level, the probe may either hang freely on the cable or lie on the bottom of the tank. The cable with the capillary can be extended using a stan-dard signal cable. For the cable connection a special Ap-lisens
170 SG cable hanger is recommended. The cable con-nection should be situated in a non-hermetically sealed box (the internal pressure inside the box should be equal to the atmospheric pressure), preventing water or other contaminants from getting into the capillary. The Aplisens
140 PP junction box is recommended For systems with long signal transmission lines, it is recommended the using of an additional Aplisens UZ-2 overvoltage protection circuit in the form of a wall-mounted box which allows the cables connection. When the probe cable is being wound up, the minimum winding diameter should be 30cm and the cable should be protected from mechanical damage. If there is a possibility

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of turbulence in the tank (for exam-ple, because of the mixer operating mixers or a turbulent inflow), the probe should be installed inside a screening tube (e.g. made of PVC). If the probe is to be lowered deeper than 100m, the cable should be hanged at steel lifting rope. Cleaning the probe diaphragm by mechanical means is strictly prohibited.

SGE-25SGE-16