LI2041 - Level sensor IFM - Free user manual and instructions

Product type	Capacitive level sensor
Brand	IFM
Model	LI2041
Technology	Capacitive
Power supply	10...36 V DC
Output current	250 mA, short-circuit protection
Protections	Reverse polarity, overload
Protection rating	IP 67, II
Ambient temperature	0...+65 °C (0...+35 °C for aqueous fluids)
Fluid temperature	0...+65 °C (0...+35 °C for aqueous fluids)
Max tank pressure	0.5 bar (with mounting accessories)
Housing material	PP (polypropylene)
Material in contact with fluid	PP (polypropylene)
Probe length	481 mm
Switching frequency	5 Hz
Operation	Level detection of fluids (conductive or non-conductive, εr>1.8)
Setting	By push button: empty and full adjustment
LED display	Green (power on), yellow (output active), red (fault/control)
Mounting	Vertical from top, minimum distance to walls 20 mm, between sensors 200 mm
Electrical connection	By electrician, de-energized
Safety	Observe national and international standards
Maintenance	Clean if deposits; perform a new adjustment if necessary

Frequently Asked Questions - LI2041 IFM

How to install the LI2041 sensor?

Mount the device vertically from the top into the tank. Use an ifm mounting accessory (ref. E43000 - E43006). The minimum distance between the sensor and the wall or bottom must be 20 mm. If multiple sensors are installed, space them at least 200 mm apart.

How to electrically connect the LI2041?

The connection must be made by an electrician. De-energize the installation before connecting. Refer to the wiring diagram in the manual.

How to perform the empty level adjustment?

Empty the tank until the fluid is at least 20 mm from the active zone. Press the programming button until the green LED flashes. The device records the empty value and automatically generates a hypothetical full value.

How to perform the full level adjustment?

Fill the tank until the active zone is covered. Press the programming button until the green LED flashes rapidly (after 5s). The device adjusts the switching threshold between the empty and full values.

What does the continuously lit red LED mean?

The continuously lit red LED indicates that the internal signal is near the switching threshold, often due to deposits. Perform cleaning or a new adjustment to avoid malfunction.

What to do if the red LED flashes rapidly after an adjustment?

This indicates an adjustment error. Possible causes: signal difference too small, incorrect order of adjustments, or device fault. Press the button once or cut off power to clear the error, then restart.

How to lock the adjustments to prevent unintentional changes?

Press the programming button for 10 seconds. The green LED flashes slowly then quickly, then turns off. The device is locked. To unlock, press again for 10 seconds.

What types of fluids can the LI2041 detect?

It detects electrically conductive or non-conductive fluids with a dielectric constant greater than 1.8. It is not suitable for acids and alkalis. Avoid non-conductive fluids that leave a permanent conductive deposit.

What is the maximum permissible pressure in the tank?

With ifm mounting accessories, the maximum pressure is 0.5 bar.

What are the dimensions of the LI2041 probe?

The probe tube length (L) is 481 mm. The minimum mounting length is 60 mm. The active zone (maximum immersion depth) is 25 mm.

USER MANUAL LI2041 IFM

Simple line drawing of a mechanical device with no text or symbols

Inhalt

10829 Berlin, 13. November 2006

Kolonnenstraße 30 L

Telefon: [phone]

Telefax: 030 78730-320

GeschZ.: | 53-1.65.13-60/06

Bechlinger Straße 34

88069 Tettnang

A = Ansprechhöhe

H = Behälterhöhe

L = Sondenlänge

L1 = Einbaulänge

L2 = Auszugslänge

M = H öhe Montageadapter

(Aktive Zone) = 25mm

S = Stutzenhöhe

1 Function and features

The sensor detects the level of media in tanks.

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

level reached level not reached

output = OFF output = ON

• The level is determined by the installation length (→ Installation).
• The unit can be adjusted to the respective application ( Programming).

Applications

• Electrically conductive or non conductive media with dielectric constant >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 electrically conductive build-up on the probe (e.g. oil polluted with metal dust).
• The unit cannot be used for acids and alkalis.

2 Installation

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)

Mount 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.

3 Electrical connection

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.

Pin1 = L+

Pin4 = output / normally open

Pin3 = L-

4 Programming

Empty adjustment

After mounting you must adjust the unit to the empty tank.

1	Empty the tankuntil the material is min. 20mm away from the active zone.
2		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).

• 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.

Full adjustment

For an optimum adjustment of the unit to your application it is recommended to carry out a full adjustment in addition to an empty adjustment as well.

1	Fill the tankuntil the medium covers the active zone.
2		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).

• 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 application.

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 adjustment.

4 Programming

Error messages

If 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 sufficient 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 medium 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).

Locking / Unlocking

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.

5 Installation and set-up / operation

After 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:

LED green lights unit is ready for operation
LED yellow lights the output has switched
LED's yellow and red flash quickly (2Hz)	short circuit of the switching output
LED red lights function check
LED red flashes quickly (2Hz) in	internal fault or unit damaged

Function check

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.

- Warning of possible malfunction

If the red LED is lit continuously, the operating conditions are no longer optimum.

It is for example possible that build-up of dirt on the probe has changed the switching level within the active zone.

You can take preventive measures to avoid a malfunction. For example readjust or clean the unit.

6 Technical data

Operating voltage [V] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 ... 36 DCCurrent rating [mA] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250;Short-circuit protection;Reverse polarity protection / Overload protectionVoltage drop [V] < 2.5Current consumption [mA] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5Switching frequency [Hz] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Maximum vessel pressure [bar] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . (when mounted with mounting accessories)

Housing material. . . . . . . . . . . . . . . . . . . . . . . . . . PP (polypropylene); TPE/VMaterials (wetted parts) . . . . . . . . . . . . . . . . . . . . PP (polypropylene)

Operating temperature [°C] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Medium temperature [°C] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Protection. IP 67, IIEMCIEC 1000-4-2 / EN 61000-4-2: .. 15kV air discharge / 8kV contact dischargeIEC 1000-4-3 / EN 61000-4-3: 10V/m, 80 ... 1000MHzIEC 1000-4-4 / EN 61000-4-4: 2kV coupling pliersIEC 1000-4-6 / EN 61000-4-6: 10V, 0.15 ... 80MHzIEC 255-5: 1kV

*for water and hydrous media

Scale drawing

			LI2043LI2042LI20
L = probe length [mm]			481273132

Pin1 = L+ Pin4 = sortie / N.F. Pin3 = L-

4 Programmation

Réglage vide