Troubleshooting of Leuze electronic DDLS 200 optical transmission

After the adjustment is completed, press any button briefly to return both devices to MAN mode. Data communication recovery.

If the communication is stable and the bar graph is good, long press the button (>2 seconds) to switch the device back to AUT mode and put it into normal operation.

Key technique: In ADJ mode, the bar chart reading directly reflects the optical power received by the other party, which is an absolute indicator of alignment quality. Make sure to maximize the bar chart (at least 8 LEDs or more).

4.3 Interpretation of Receiving Level Bar Chart

10 LED lights are all on: good reception, sufficient performance margin, OUT Warning not activated.

Yellow light area (usually 5-7 LEDs): Warning range, data can still be transmitted normally but there is no margin, OUT Warning activated (output Vin-2 V).

Red light area (<5 LEDs): Off range, data communication interrupted, OUT Warning activated.

Note: At the maximum detection distance (200 m), even with optimal alignment, the bar graph may not achieve full deviation, which is a normal phenomenon.

Fault diagnosis and common problem elimination

5.1 The PWR/UL LED does not light up after power on

Possible cause inspection and resolution

The voltage between Vin and GND measured without power supply voltage should be 18... 30 V DC

Check the terminal wiring for reverse polarity of the power supply, with Vin connected to positive and GND connected to negative

Internal hardware failure returned to manufacturer for repair

5.2 PWR/UL LED flashing

Possible cause inspection and resolution

Switch input IN activated (S1=Off and IN voltage<2 V) Check IN terminal voltage or S1 switch position

If the hardware error still flashes after excluding the input cause, return for repair

5.3 Data communication interruption, but the bar graph displays normally

Possible cause inspection and resolution

Instantaneous obstruction of the optical path (such as robotic arms, flying insects). Check if there are periodic obstructions on site

Inspection of INTERBUS terminal Tx/Rx wiring for broken or poor contact of bus cable

Two devices with mismatched frequencies confirm that one is. 1 (f1) and the other is. 2 (f2)

5.4 The display of the image is too low, and OUT Warning is activated

Possible cause inspection and resolution

Cleaning glass windows with optical window contamination (using glass cleaner and avoiding acetone solvents)

Align the offset and perform fine alignment again (follow the steps in Chapter 4)

The ambient light is too strong (>10000 Lux) and meets the standard, but it is possible to consider installing a light shield

Check if the actual distance is ≤ 200 m (or 120 m) when the working distance of the equipment exceeds the specifications

5.5 Bus communication failure, Tx/Rx LED flashing abnormally

For INTERBUS, a green flashing Tx LED (at high rates) may indicate a bus communication failure. Check the baud rate setting (fixed at 500 kBit/s) and bus cable length.

Ensure that the S4 switch is in the correct position (In/Out).

Maintenance and Cleaning

DDLS 200 is maintenance free during normal operation, but the optical window requires regular cleaning. The manual recommends cleaning once a month or when triggered by an OUT Warning.

Cleaning steps:

Disconnect the power supply (not mandatory, but recommended).

Gently wipe the optical window with a soft cloth and standard glass cleaner.

Do not use solvents containing acetone, as it may damage the glass coating.

Check heating function: In low-temperature environments, if frost appears on the window, check if the optical heating is working (current consumption should be 800 mA). If the heating fails, the equipment needs to be replaced.

System replacement and upgrade suggestions

When the original DDLS 200 is discontinued or cannot be repaired, engineers may consider the following solutions:

Same model replacement: Confirm that the spare parts are of the same model (such as pairing DDLS 200/2001-YY with. 2-YY). Pay attention to frequency identification (. 1 and. 2 must be paired).

Upgraded to a new model: Leuze has subsequently launched series such as DDLS 500/508, supporting higher speeds and longer distances. When replacing, attention should be paid to the electrical interface (possibly changed from INTERBUS to PROFINET) and installation dimensions.

Repair service: Internal optical components, laser diodes, or electronic boards can be replaced through Leuze official or third-party repair providers.

Important reminder: After replacement, the complete mechanical installation and fine alignment process must be re executed, and the old alignment data cannot be directly used.