- For limit level sensing of liquid, and bulk-solid and powder materials
- Xi version for usage in explosive areas
- Direct mounting into various containers, silos, vessels, tanks, filling inlets, reservoirs, etc.
- Sensitivity and hysteresis fluently adjustable
- NPN, PNP, NAMUR output (EN 60947-5-6)
- Material of housing and electrode from stainless steel
Capacitive level sensors (switches) DLS® are designed for limit level sensing of liquids, bulky solid and powder materials in vessels, containers, silos, tanks, reservoirs, etc. Sensors are made in several modifi cations of sensing electrodes – short and long rods or rope. The electrodes can be coated what has important sense in case of adhesive, aggressive or electrically conductive media sensing. The process coupling at the housing can be with thread M27x2, M30x1.5, G3/4" or with Tri-clamp coupling. Electric connection is provided by means of permanent cable lead (variant B) or by means of connector (variant C). Output performances – transistor outputs with open collector (NPN, PNP) or NAMUR output.
There are next performances available: N – For normal atmospheres; Xd – For use in fl ammable dust atmospheres; Xi – Explosion proof – intrinsically safe for hazardous (explosive) areas; XiM – Explosion proof – intrinsically safe for use in mines with methane or fl ammable dust presence danger (see technical specifi cations).
FEATURES OF VARIANTS
- DLS –27_ –10
- Uncoated short bar electrode for sensing non-adhesive bulk-solid (powder) materials (sand, sugar) and electrically non-conductive liquids (oils, diesel, petrol), horizontal mounting.Electrode length 50 mm or 100 mm.
- DLS –27_ –11
- Fully coated short bar electrode for sensing electrically conductive liquids (water). Assembly into a side wall of vessel or into a pipe. Electrode length 30 mm.
- DLS –27_ –20
- Semi-coated rod electrode for sensing light-bulk solid or powder materials (plastic granulates, flour, cement) and non-conductive liquids (plant oils), horizontal, slant or vertical mounting. Electrode length from 0.1 m to 1 m.
- DLS –27_ –21
- Fully (FEP) coated rod electrode for sensing electrically conductive liquids (water solutions, water), adhesive and aggressive materials, horizontal or vertical mounting. Electrode length from 0.1 m to 1 m.
- DLS –27_ –22
- Fully (PFA) coated rod electrode for sensing electrically conductive liquids (water solutions, water), adhesive and aggressive materials, horizontal or vertical mounting. Electrode length from 0.1 m to 1 m.
- DLS –27_ –30
- Dismountable rod uncoated electrode for sensing bulk-solid (powder) materials and conductive or non-conductive liquids. Mounting from the top (vertically) or slant from the side. Electrode length from 0.1 m to 3 m.
- DLS –27_ –31
- Fully coated rod electrode for sensing aggressive electrically conductive liquids (water, solutions of chemicals), vertical mounting. Electrode length from 0.1 m to 2 m.
- DLS –27_ –40
- Uncoated stainless steel rope electrode and weight for general purpose in deeper silos (bulk-solid and powder materials sensing – sand, gravel, cement) or hoppers (liquids sensing), vertical mounting. Electrode length from 1 m to 6 m.
RANGE OF APPLICATION AND INSTALLATION OF MAIN VARIANTS
DLS –27_ –10
- Is produced in two versions - with 50 mm or 100 mm length electrode. Short version (E50) is suitable for clean non-conductive liquids level sensing (oils, diesel, petrol, etc.). Longer version (E100) is designed for non-adhesive bulk-solid or non-adhesive powder materials (plastic granulates, sand, sugar, grains, etc.) and other non-conductive liquids (lubricants, plant oils). Sensor is specifi ed to be mounted directly into a vessel or container wall (horizontal position) by means of welding fl ange or stainless steel fi xing nut. In case of level sensing of low-permittivity media in non-conductive containers it is recommended to mount the sensor on auxiliary metal-plate electrode with min. 200 cm2 area.
DLS –27_–11
- Is specified for limit level sensing of electrically non-adhesive conductive liquids (water and water solutions). It is possible to use it for detection of boundary between different permittivity liquids (e.g. water - oil). Sensor is mounted directly into the side wall of the vessel or in a pipe (horizontal position) by means of normal or stainless steel welding fl ange.
DLS –27_–20
- Is designed for limit level detection of light-bulk solid materials (plastic granulates) or powder materials (fl our, cement, limestone powder, detergents, etc.) and for materials with variable humidity (feeding mixtures, wood sawdust, etc.). It is possible to use it for non-conductive fl uids with up to 2% of water (plant oils, liquid propane, etc.). The sensor with electrode longer than 300 mm is recommended to mount in vertical position only. Sensor is mounted directly into a vessel or container wall in horizontal (up to E300), slant or vertical position by means of welding fl ange or stainless steel fi xing nut. We should minimize the hollow spaces between the electrode and the wall where the material can sediment (see application notes). In case of level sensing in non-conductive containers it is recommended to mount the sensor on auxiliary metal plate electrode with min. 400 cm2 area.
DLS–27_–21, 22
- Is specified for conductive liquids level sensing (water, water solutions, mud, etc.). It is designed for horizontal (up to E300) or vertical installation directly in the wall of a vessel. It reacts on partial or full immersion of the electrode (dependent on adjusted sensitivity). The less is the sensitivity the better is resistance to an adhered rests of media. Sensor is mountable directly into wall of a vessel in horizontal or vertical position by means of welding fl ange. DLS–27_–22 type is more resistant to aggressive liquids.
DLS –27_ –30
- Is designed for universal use in vertical position for limit level detection of liquids (conductive and non-conductive) and bulk-solid and powder materials. It is not recommended to install the sensor into closed vessels where intensive condensation occurs. Electrically conductive liquids are sensed just by touch of the end of electrode. To react to non-conductive liquid or solid material it is necessary 5 ÷ 20% dip into a medium dependently on the permittivity of sensed medium and set sensitivity. Sensor is mounted directly into a tank, vessel, container or basin in slant or vertical position by means of welding fl ange or stainless steel fi xing nut. In case of level sensing of low-permittivity media in non-conductive containers it is recommended to mount the sensor on auxiliary metal-plate electrode with min. 500 cm2 area.
DLS –27_ –31
- Is designed for limit level detection of conductive liquids (water and solutions of chemicals). It is possible to install the sensor into closed vessels, tanks, basins, etc. The sensor reacts to liquid level after 2 ÷ 20% dip into a liquid dependently on the permittivity of sensed medium and set sensitivity. Sensor is mounted directly into a vessel, tank or open basins in vertical position by means of welding fl ange or fi xing nut. When installed into an open basin it is necessary to ground the housing of sensor or to connect it with sensed liquid. For this purpose it is possible to use any metallic ever immersed object (pipe, etc.).
DLS –27_ –40
- Is specified for versatile use for limit level detection of liquids (conductive and non-conductive) and bulk-solid and powder materials in depths down to 6 m. It is not recommended to install the sensor into closed vessels where intensive condensation occurs. Electrically conductive liquids are sensed just by touch of the end of electrode. To react to non-conductive liquid or solid material it is necessary 5 ÷ 20% immersion into a material. Sensor is mounted directly into a vessel, tank or open basins in vertical position by means of welding fl ange or fi xing nut. When installed into an open basin it is necessary to ground the housing of sensor or to connect it with sensed liquid. For this purpose it is possible to use any metallic ever immersed object (pipe, etc.).
SENSOR SETTING
The sensor is factory adjusted for basic sensitivity. The sensitivity is set by trimmer located under the left cover screw on the rear side. Clockwise turning makes the sensitivity lower, reverse direction turning makes the sensitivity higher. The hysteresis is set by trimmer located under the right cover screw. Clockwise turning makes the hysteresis higher, reverse direction turning makes it lower. The lower the hysteresis is, the higher sensitivity is possible to obtain, but the resistance against various disturbances get worse. For detailed information please read at the instructions manual.
ACCESSORIES
Standard (included in the level sensors price)
- 1 pcs. Seal (asbestos free)
- 1 pcs. Screwdriver for adjustment (each 5 pcs.)
Optional (for extra charge)
- Extra cables (over the standard length 2 m)
- Connector plug (type ELWIKA or ELKA)
- Normal steel welding fl ange
- Stainless steel welding fl ange
- Stainless steel fi xing nut
- Other seals (PTFE, Al, etc.)
CORRECT SPECIFICATION EXAMPLES
DLS–27N–10–B–NO–M27 E100 cable 5 m
- (N) Normal performance; (10) Uncoated bar electrode, (B) Cable outlet with 5 m length cable; (NO) Output type NPN with open state at non-activated electrode; (M27) Metric thread M27x2 process connection; (E100) Electrode length 100 mm
DLS–27NT–21–C–PC–G E580
- (NT) Normal high temperature performance; (21) Fully coated rod electrode (FEP); (C) Connector; (PC) Output type NPN with closed state at non-activated electrode; (G) Pipe thread G3/4" process connection; (E580) Electrode length 580 mm.
DLS–27Xi–30–C–RO–M30 E1420
- (Xi) Explosion-proof performance; (30) Dismountable uncoated electrode; (C) Connector, (RO) Output type NAMUR with lower current at non-activated electrode, (M30) Metric thread M30x1,5 process connection; (E1420) Electrode length 1420 mm.
DLS–27Xd–20–D–NC–G E430 cable 3 m
- (Xd) Flammable dust areas performance; (20) Partly coated electrode; (D) Cable outlet; (NC) Output type PNP with closed state at nonactivated electrode; (M30) Metric thread M30x1,5 process connection; (E430) Electode length 430 mm.
SAFETY, PROTECTIONS, COMPATIBILITY AND EXPLOSION PROOF
Level sensor DLS–27 is equipped with protection against electric shock on electrode, reverse polarity, output current overload, short circuit and short time over voltages.
Electromagnetic compatibility is provided by conformity with standards EN 55022 / B, EN 61326-1, EN 61000-4-2, -3 ,-4, -5 and -6. Explosion proof DLS–27Xi, XiM and Xd is examined by FTZÚ - AO210 Ostrava - Radvanice, certifi cate No. FTZÚ 02 ATEX 0234X and FTZÚ 10 ATEX 0092X.
