Pepperl+Fuchs NBB8-18GM50-E2 M18 Inductive Sensor

NBB8-18GM50-E2 M18 flush PNP inductive sensor for harsh environments

The NBB8-18GM50-E2 is a cylindrical M18 threaded inductive proximity sensor from Pepperl+Fuchs with a rated operating distance of 8 mm, flush mounting, a PNP normally-open output and a fixed 2 m PVC cable. It is built for rough industrial duty: the datasheet lists high shock resistance, an extended temperature range from -40 to +85 °C and an extended operating voltage range of 6 to 36 V.

Reading the part number: NBB means a standard-range (flush) inductive sensor, 8 is the rated operating distance in millimetres, 18GM50 identifies the M18 threaded brass housing with a 50 mm length class, and E2 stands for the 3-wire DC PNP normally-open output. Versions with plug connectors carry V1 in the name and are separate parts.

Seven Star LLC supplies this sensor in Oman and the GCC as an independent supplier in Muscat.

Technical specifications of the NBB8-18GM50-E2

Reliability data and standards for the NBB8-18GM50-E2

For users who need functional-safety inputs, the datasheet of the NBB8-18GM50-E2 gives an MTTFd of 1610 years, a mission time of 20 years and a diagnostic coverage of 0 %. These numbers describe the random hardware failure rate only; the sensor carries no safety function claim of its own. It conforms to EN IEC 60947-5-2 for proximity switches and the VDMA 24364-C1/T100°C-W requirement for paint-wetting-impairment-substance freedom, which matters in paint shops and automotive lines.

Protection class II with a rated insulation voltage of 36 V and impulse withstand voltage of 500 V means the sensor is intended for low-voltage supplies only. Do not connect it to mains and use a regulated 24 V DC supply with a fuse on long cable runs.

Why the NBB8-18GM50-E2 suits rugged mounting positions

The NBB8-18GM50-E2 doubles the rated distance of the M12 sibling to 8 mm with a flush M18 body. That extra gap protects the sensing face from impacts when a cam, flange or moving plate passes at some distance, and it tolerates more mechanical play in brackets. The assured distance is 0 to 6.48 mm, so mount the sensor so the target always lies inside that figure including tolerances and wear.

Switching frequency is lower than for the M12 type, 1350 Hz against 2550 Hz, because the larger coil needs more time; check this if you count fast pulses.

Detection with different metals

The datasheet gives reduction factors for the NBB8-18GM50-E2: aluminium 0.38, copper 0.35, stainless steel 304 at 0.74 and brass 0.47. For an aluminium cam the real operating distance falls to about 3 mm (8 mm x 0.38), so a small gap is required. The standard target is 24 mm x 24 mm x 1 mm mild steel; smaller targets detect at shorter distance, and the characteristic curves on the datasheet show the radial offset allowed.

Where the NBB8-18GM50-E2 fits and related parts

Use the NBB8-18GM50-E2 when M18 threaded mounting holes already exist, as on many valve and actuator brackets. The smaller NBB4-12GM50-E2 fits tighter spaces, and the connector version carries a V1 suffix. For fieldbus networks, the NCN8-18GM60-B3B-V1 is an AS-Interface sensor in the same M18 envelope.

Selection and ordering checklist

• Target material, size and distance range including tolerances.
• PNP input on the PLC and normally-open logic.
• Fixed 2 m cable or connector option.
• Mounting torque limit of 30 Nm.
• IP rating and washdown conditions.
• Ambient temperature and shock.

Installation, commissioning and maintenance of the NBB8-18GM50-E2

Mount the sensor with the supplied self-locking nuts at no more than 30 Nm, and keep the face flush or proud of the bracket. Confirm the switching point with the real target at both ends of its travel; the yellow LED shows each switching event. During maintenance, wipe off magnetic swarf, which can stick to the face and create false detections.

Replace sensors if cable insulation is cut, because moisture ingress through the cable can lead to intermittent switching.

Typical applications in Oman and the GCC

The NBB8-18GM50-E2 is used for valve position proofs, rotating machine checks, gate limits and conveyor equipment in plants and utilities across Oman and the GCC. Heat and sand are the main field stresses; the brass body with PBT face and high ingress protection copes with both, while cable routing should be shielded from solar heat.

Family comparison

Information to send with an RFQ

• Part number NBB8-18GM50-E2 and quantity
• Target material and size
• Cable length or connector
• PLC input type
• Operating temperature
• Delivery location

Documents and quotation

The manufacturer datasheet for NBB8-18GM50-E2 is attached on this page, so you can check wiring, approvals and dimensions before ordering. Send the exact part number, quantity and delivery location in Oman or the GCC and Seven Star LLC will reply with a quotation.

Seven Star LLC is an independent supplier in Muscat and is not the manufacturer; confirm availability, lead time and any project approval requirements in your RFQ.