SICK WL250-2 (01) PDF DOCUMENT

Please adhere to the following safety guidelines when operating the SICK WL250-2 sensor:

• Read the operating instructions before commissioning.

• Connection and settings are only to be performed by trained specialists.

• The SICK WL250-2 is not a safety component in accordance with the EU Machinery Directive.

• Only for use in applications in accordance with NEMA 79.

• The SICK WL250-2 is UL-approved for use with a Class 2 power source only.

• DC adapters intended for use with the device are available as accessories.

• It is important to protect the device from moisture and contamination.

• The operating instructions contain information required during the life-cycle of the sensor.

To put the SICK WL250-2 into operation, connect the cable to the power supply as follows, depending on your model:

For SICK WL250-2P (PNP, L.on / D.on):

1 = brown wire, connected to +V

3 = blue wire, connected to M

4 = black wire, for output Q (L.on), which is high when the light path is interrupted.

2 = white wire, for output Q (D.on), which is high when the light path is clear.

Connect load between output Q (black) or Q (white) and M. The switchable output selection (L.on/D.on) is achieved by connecting wire 2 (white).

For SICK WL250-2N (NPN, L.on / D.on):

1 = brown wire, connected to +V

3 = blue wire, connected to M

4 = black wire, for output Q (L.on), which is low when the light path is interrupted.

2 = white wire, for output Q (D.on), which is low when the light path is clear.

Connect load between +V and output Q (black) or Q (white). The switchable output selection (L.on/D.on) is achieved by connecting wire 2 (white).

For SICK WL250-2R (Relay, L.on / D.on):

1 = brown wire, connected to +V

3 = blue wire, connected to M

The relay is in an energized state when the light path is clear. It features a changeover contact with a center tap. With a clear light path and energized relay, contact 4 makes with 5 (normally open) and breaks from 2 (normally closed). With an interrupted light path and de-energized relay, contact 4 makes with 2 (normally closed) and breaks from 5 (normally open). The switchable output selection (L.on/D.on) is achieved by connecting either the normally open or normally closed contact.

The SICK WL250-2 features a yellow LED that indicates the switching state:

For light switching models:

• With a clear light path, the yellow LED is ON.

• With an interrupted light path, the yellow LED is OFF.

For dark switching models:

• With a clear light path, the yellow LED is OFF.

• With an interrupted light path, the yellow LED is ON.

The sensor also features a red LED which serves as a signal strength and contamination indicator. This LED is explained in the alignment procedure.

Follow these steps to mount the SICK WL250-2 sensor:

1. Mount the photoelectric sensor to a holder (optional).

2. Mount the sensor and reflector opposite each other. The brown and blue wires of the photoelectric sensor must be connected to the power supply. For DC devices, connect the black or white wire to the load.

3. Align the sensor with the reflector. The yellow LED should illuminate. With optimum alignment and sufficient operating reserve, the switching threshold is not exceeded even if the lens becomes contaminated.

4. To determine the point of maximum signal strength, use the signal strength indicator (red LED). Slowly pan the sensor horizontally and vertically across the reflector. The red LED will illuminate when the receiver signal is at its strongest. With optimum alignment, the red LED indicates signal strength. When the signal strength is weak or there is contamination, the red LED will flash. If the red LED does not illuminate even with a reflector, it indicates contamination or a faulty sensor.

5. Set the sensitivity adjuster (potentiometer). With a standard object size and distance, set the sensitivity using the sensor with and without the object present. With small, fast, or transparent objects, you may need to reduce the sensitivity until the sensor just switches. Set the sensitivity so that the switching threshold is correctly set. For applications where only high sensitivity is needed, turn the sensitivity adjuster to maximum.

The SICK WL250-2 photoelectric retro-reflective sensor meets the specified sensing distance with optimal alignment to the reflector. Alignment is indicated by the signal strength indicator (red LED). When used in industrial areas, this can cause interference.

The SICK WL250-2 sensor does not require any maintenance. We recommend cleaning the front screens and checking the screw connections and plug-in connections at regular intervals. No modifications may be made to the devices.

Notes on Technical Data:

Sensing range also specified for:

• Reflector PL20A: 250 mm … 6 m

• Reflector tape “Diamond Grade” (100 x 100 mm²): 250 mm … 5 m

Technical data for SICK WL250-2R (Relay):

• Supply voltage V_S: 24 … 240 V AC/DC

• Current consumption: max. 50 mA

• Overvoltage category: 2

• Pollution degree: 3

• Pin/wire assignment: As per drawing

Circuit Protection Key:

A = V_S connections reverse-polarity protected

B = inputs/outputs reverse-polarity protected

C = outputs short-circuit proof

D = overcurrent and short-circuit protection