PU30-TDPB, LANBAO, fork light barrier, Sn 30 mm, PNP, NO and NC, cable 2 m PVC

PU30-TDPB – Fork (U-shaped) light barrier

PU30-TDPB (LANBAO) is a fork (U-shaped) light barrier. The emitter and receiver are fixed opposite each other in one fork frame, so no alignment is needed — the object simply passes through the fork gap.

Key features

• Sensing distance 30 mm.
• PNP output, NO and NC contact (programmable) – connects to a PLC digital input or a relay coil.
• Supply 10–30 V DC.
• Connection: cable 2 m PVC.

Technical specifications PU30-TDPB

Wiring of PU30-TDPB by wire colours

The colour coding complies with IEC 60947-5-2. Always compare the actual pin and wire assignment with the diagram in the sensor datasheet (Downloads tab).

Wiring of a four-wire cable with two outputs.

Typical applications

• detection of marks, labels and tags as they pass
• counting small parts falling down a chute
• checking the presence of wire, tape or foil
• position monitoring with high repeatability without adjustment
• use where aligning a two-part barrier would be time-consuming

How to choose and what to watch out for

• PNP output (switches plus) matches the standard PLC digital inputs used in Europe. For NPN-type inputs, choose the corresponding variant with the same sensing distance.
• NO and NC contact: the output logic can be selected by wiring, so one model covers both the normally open and normally closed function.
• Cable outlet: the cheaper variant, but replacing the sensor requires pulling the entire cable. If you need quick replacement, choose a model with a connector (suffix -E1 for M8, -E2 for M12).

PNP or NPN – and what happens if you mix them up

PNP switches the positive pole, so it sends plus to the PLC input. It is the European standard and matches standard digital inputs. NPN switches minus and is used mainly in Asian equipment. If mixed up, the sensor either does not switch at all or reports a permanently active state — it usually will not be damaged, but it will not work.

This model has a PNPoutput. If you need NPN, a variant with the same sensing distance is available — contact us and we will recommend the code.

NO or NC – and why it is not just a matter of convenience

NO (normally open) is an output that is active on detection. NC (normally closed) is active at rest and opens on detection. The difference is a safety one: with NC, a broken wire causes the same reaction as a detection, so the fault shows up immediately. With NO, a broken cable remains unnoticed until someone tries to switch.

This model has the contact NO and NC (programmable).

Frequently asked questions

Does PU30-TDPB have a PNP or NPN output?

PU30-TDPB has a PNP output with NO and NC contacts (programmable). It therefore matches the standard PLC digital inputs used in Europe.

What is the sensing distance of PU30-TDPB?

The sensing distance (Sn) is 30 mm.

How is PU30-TDPB connected?

PU30-TDPB is supplied with the connection: cable 2 m PVC. The cable is part of the sensor; the other end is free for connection to a terminal block.

How is PU30-TDPB wired by wire colours?

Brown wire to supply plus, blue to minus, black is the NO output and white the NC output. The coding complies with IEC 60947-5-2.

Does a fork light barrier need alignment?

No. The emitter and receiver are aligned on the same axis in a common frame at the factory, so the sensor is simply screwed on and works. This is its main advantage over a two-part barrier.