LI2042 - Level sensor IFM - Free user manual and instructions

USER MANUAL LI2042 IFM

• The unit detects by direct contact with the medium whether the requested level is reached and indicates this by a switched signal:

• The level is determined by the installation length (→ Installation).

• The unit can be adjusted to the respective application (→ Program- ming).

• Electrically conductive or non conductive media with dielectric con- stant >1.8 are detected.

• The unit is virtually immune to build-up of almost all media on the probe. The position of the switching level within the active zone can however change with build-up. Possibly critical media:

• Electrically non conductive media which leave a permanent electri- cally conductive build-up on the probe (e.g. oil polluted with metal dust).

• The unit cannot be used for acids and alkalis. Page 22 Applications 1 Function and features 3 LED’s (green, yellow, red) programming button probe active zone (25mm) level reached level not reached output = OFF output = ONMount the unit vertical from the top. Mounting length (L3): minimum 60mm. For safe and easy mounting use the ifm mounting accessories (Order no. E43000 - E43006). Maximum vessel pressure when mounted with mounting accessories: 0.5bar.

• If possible, mount the unit in the middle of the tank when it is installed in small plastic tanks:

• When installed in metal tanks the distance between sensor and tank wall / tank bottom must be min. 20mm.

• When several units are installed in a tank, the distance between them should be min. 200mm. The unit must only be connected by an electrician. The national and international regulations for the installation of electrical equipment must be observed. Disconnect power before connecting the unit. Page 23 ENGLISH 2 Installation 3 Electrical connection

A = response level H = height of the tank L = probe length L1 = installation length L2 = outside length L3 = mounting length M = hight of the adapter S = height of the neck MET = maximum immersion depth (= active zone, 25mm)

Pin1 = L+ Pin4 = output / normally open Pin3 = L-After mounting you must adjust the unit to the empty tank.

• During the empty adjustment the unit determines a measured value for the empty state,

• automatically generates a hypothetical value for the full state (from the measured value for the empty state and a factory predefined signal difference).

• It then sets the optimum switching threshold between the two values. The unit is then ready for operation. For an optimum adjustment of the unit to your application it is recom- mended to carry out a full adjustment in addition to an empty adjust- ment as well.

• During the full adjustment the unit adopts the measured value for the empty state determined during the empty adjustment,

• determines a measured value for the full state and

• sets the optimum switching threshold between the two values. This ensures an optimum adjustment of the unit to your appli- cation. You can repeat the full adjustment as often as you wish. The stored value for the empty state is not overwritten by the full adjustment. When an empty adjustment is made again the previously defined values are overwritten/replaced by the newly determined values. So always carry out the empty adjustment first, then the full adjust- ment. Page 24 Empty adjustment Full adjustment 4 Programming

Press the programming button until the green LED flashes (= the unit is in the adjustment mode). After adjustment the green LED is lit continuously (the unit is in the operating mode). Empty the tank until the material is min. 20mm away from the active zone.

Press the programming button until the green LED flashes quickly (= the unit is in the adjustment mode). The LED first flashes slowly (about 1Hz), after 5s it flashes double as quickly (about 2Hz). After adjustment the green and yellow LED's are lit continuously (the unit is in the operating mode). Fill the tank until the medium covers the active zone.

5 ... 10sIf the adjustment to the empty or full state is not possible, the red LED flashes quickly after the adjustment attempt (about 2Hz). To delete this error message press the programming button once or disconnect and then connect power again. The previous adjustment values remain unchanged. Remove the error cause and then make the adjustment again. Avoid the faults the operator may have made.Possible reasons for an error message:

• The signal difference between the empty and full state is too small (e.g. adjustment to the empty and full state without suffi- cient change of the level; or too low density of the medium).

• The signal change between the empty and full state is in the wrong order (e.g. adjustment to the empty state when the vessel is full and then adjustment to the full state when the vessel is empty).

• Fault during the empty adjustment (e.g. distance between the medi- um and active zone is too small or empty adjustment made when there is direct contact with an electrically conductive medium, e.g. water). Faults of the unit can also disturb the adjustment and result in a fault message:

• Electronic fault or sensing zone of the unit damaged.

• Internal fault (can only be deleted by disconnecting and connecting power again, hardware reset). The stored adjustment values can be protected against unauthorised programming: Press the programming button for 10s. The green LED first flashes slowly (about 1Hz), after 5s more quickly. As soon as the indication goes out the unit is locked. Then the green LED is lit, the unit is in the operating mode. To unlock the unit press the programming button for 10s. After about 10s all LEDs go out briefly, the unit is unlocked. Units are delivered from the factory in the unlocked state. Page 25 ENGLISH Error messages Locking / Unlocking 4 ProgrammingAfter mounting, wiring and setting check whether the unit operates correctly. Empty and fill the tank and check whether the unit switches correctly and whether the LED's correctly indicate the operations. Display by LEDs: The red LED indicates no malfunction of the unit, it indicates that the internal sensor signal is near the switching threshold. 2 cases can be distinguished:

• Normal operation/safe operation The red LED is lit temporarily when the level of the medium approaches the response level or falls below the response level.