Features
- for continuous level measurement of non-aggressive liquids (without hard dirtiness) in non-pressure reservoirs, drill holes, water wells, sumps, tanks and swimming-pools
- 2-wire connection with 4 ÷ 20 mA output
- 3-wire connection with 0 ÷ 10 V output
- optional arbitrance range up to 200 m (H2O)
- over voltages protection inside probe and at the beginning of cable
- carrying loop for easy fixation in a big depth
Description
Hydrostatic level meters HLM-25 and HLM-16 are compact measuring devices containing silicon tenzometric sensor and evaluation electronics in stainless housing. From the probe housing coming out 2-wire cable with capillary (for comparing atmospheric pressure into probe).
Opposite end of the probe has stainless dismountable cover (to protect damage of membrane).
Hydrostatic level meters HLM are intended for continuous level measurement of non-aggressive liquids without hard dirtiness in non-pressure reservoirs, drill holes, water wells, sumps, tanks and swimming-pools. The principle of hydrostatic level measurement is the dependability of pressure on the height of the column of measured liquid.
For measuring it is possible to use a standard measuring ranges or directly define required range. On the level meter are not any setting elements.
Technical specification
Working areas (acc. to EN 60079-14) and performance
HLM-16N non-explosive
HLM-25N non-explosive
Installation
When immersed to the reference level the probe may hang freely on the cable or lie on the bottom of the tank. The cable with the capillary can be extended using a standard signal cable. The cable connection should be situated in a non-hermetic box (with internal pressure equal to atmospheric pressure), preventing water or other contaminants from reaching the capillary. When the probe cable is wound up, the winding diameter should be at last 30 cm and the cable should be protected from mechanical damage.
The cable supplied by the manufacturer should not be shortened. In tanks where there is a possibility of turbulence (where mixers operate or where is a turbulent inflow), the probe should be installed in a screening tube (e.g. made from PVC). For easier hanging of the probe a line can be attached to the carrying loop. The probe diaphragm must not be mechanically cleaned.
Safety, protections and compatibility
Level meter is equipped with protection against reverse polarity, output current overload, short circuit and short time over voltages.
The protection against electric shock is done by safety voltage use.
Electromagnetic compatibility is provided by conformity with standards: EN 55022/B, EN 61000-4-2, EN 61000-4-3, EN
61000-4-4, EN 61000-4-5, EN 61000-4-6.
