Pepperl+Fuchs NBB4-12GM50-E2 M12 Inductive Sensor

NBB4-12GM50-E2 M12 flush PNP inductive sensor for harsh environments

The NBB4-12GM50-E2 is a cylindrical M12 threaded inductive proximity sensor from Pepperl+Fuchs with a rated operating distance of 4 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, 4 is the rated operating distance in millimetres, 12GM50 identifies the M12 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 NBB4-12GM50-E2

Reliability data and standards for the NBB4-12GM50-E2

For users who need functional-safety inputs, the datasheet of the NBB4-12GM50-E2 gives an MTTFd of 1607 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.

How the NBB4-12GM50-E2 detects metal

The sensor creates a high-frequency magnetic field at its green PBT face. A metal target entering the field damps the oscillator, and the electronics switch the PNP output at the rated distance. The NBB4-12GM50-E2 gives 4 mm for the standard mild steel target of 12 mm x 12 mm x 1 mm; other metals reduce the distance by the factors in the table, so an aluminium target is detected at roughly 40 % of the steel distance (4 mm x 0.4 is about 1.6 mm).

Flush mounting means the housing can be set into a metal bracket up to the sensing face without detuning the field, which protects the face on moving machinery. The very high switching frequency of 2550 Hz makes this M12 type suitable for counting teeth, bolts or fast-moving cams.

Where the NBB4-12GM50-E2 fits and related parts

Choose the NBB4-12GM50-E2 where an M12 flush sensor with a fixed cable is needed and the control input is a PNP sinking type. For an M18 body with 8 mm range, the NBB8-18GM50-E2 is the direct larger sibling; for connector versions look at the V1 variants of the same series, and for hazardous areas use NAMUR types such as the NJ2-12GK-SN with an isolated barrier.

Selection and ordering checklist

• Target material and size: apply the reduction factor and keep a margin below the assured distance of 3.24 mm.
• PNP versus NPN input on the PLC; this part is PNP, normally open.
• Cable (2 m fixed) or connector, since this part has fixed cable.
• Cable routing and bend radius over 10 times the cable diameter.
• Washdown, dust and shock: IP65 to IP69 rating is listed.
• Ambient temperature range -40 to 85 °C.

Installation, commissioning and maintenance of the NBB4-12GM50-E2

Fit the sensor with the two supplied self-locking nuts and keep the tightening torque at or below 10 Nm. Hold the specified free zone around the face if neighbouring sensors or metal masses could interact, and align the target through the mounting slot rather than at the cable. The yellow LED confirms switching during setup.

There is no adjustment to make. If a sensor stops switching, check supply voltage between brown and blue, then the black output with a multimeter; mechanical damage to the cable jacket is the most frequent cause of failures on moving machines.

Typical applications in Oman and the GCC

The NBB4-12GM50-E2 is used on pump skids, valve actuators, conveyor lines and packaging equipment in oil, gas, water and industrial plants in Oman. With a wide temperature range and marine listing, it also fits equipment on offshore structures, though hazardous-area use requires an intrinsically safe sensor, not this one.

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Information to send with an RFQ

• Part number NBB4-12GM50-E2 and quantity
• Target material and size
• Required cable length or connector
• PLC input type
• Operating temperature
• Delivery location

Documents and quotation

The manufacturer datasheet for NBB4-12GM50-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.