M12 Series Metal Inductive Proximity Switch

The DAIDISIKE M12 series metal inductive proximity switch is a high-performance cylindrical electromagnetic sensor designed for industrial automation. It uses DC three-wire power supply, supports NPN / PNP outputs, and detects metal objects without contact.

M12 cylindricalFlush 2 / 4 mm · Non-flush 4 / 8 mmNPN / PNP · NO / NC / NO+NC10 – 30 V DCIP67 / IP68RoHS · CE · UL
inXfrWA✉︎PTG
DAIDISIKE M12 inductive proximity switch — feature illustration

Product Introduction

The DAIDISIKE M12 series metal inductive proximity switch is a high-performance cylindrical electromagnetic proximity sensor designed for industrial automation applications. This series uses DC three-wire power supply, supports NPN and PNP output modes, and can detect metal objects without physical contact. The product complies with RoHS standards, has an IP67 protection rating, and is suitable for harsh industrial environments. The series includes various models such as M12 × 35 (flush) and M12 × 45 (non-flush), with detection distances ranging from 2 mm to 8 mm.

The sensor housing is made of nickel-plated brass for high corrosion resistance, and is equipped with an LED indicator for easy status monitoring. This product is widely used in mechanical manufacturing, automotive industry, food processing and similar fields for object position detection, counting and limit control.

Specifications — Flush vs Non-flush

ParameterM12 Flush TypeM12 Non-flush Type
BrandDAIDISIKEDAIDISIKE
Product nameM12 Metal Inductive Proximity Switch (Flush)M12 Metal Inductive Proximity Switch (Non-flush)
Installation methodFlush (Shielded)Non-flush (Unshielded)
Detection distance (standard iron target)2 mm / 4 mm (Standard / Extended)4 mm / 8 mm (Standard / Extended)
Output modeNPN / PNP — NO / NC / NO+NCNPN / PNP — NO / NC / NO+NC
Operating voltage10 – 30 V DC (some models support 6 – 36 V DC)10 – 30 V DC (some models support 6 – 36 V DC)
Maximum load current100 mA / 200 mA / 300 mA100 mA / 200 mA / 300 mA
No-load current< 10 mA< 10 mA
Voltage drop< 1.5 V / < 2 V< 1.5 V / < 2 V
Leakage current< 0.01 mA< 0.01 mA
Switching frequency500 Hz / 1000 Hz / 2000 Hz300 Hz / 500 Hz / 1000 Hz
Response time< 0.5 ms / < 1 ms< 0.5 ms / < 1 ms
Switch hysteresis< 15 % (Sr)< 15 % (Sr)
Repeatability< 3.0 % (Sr) / < 5 %< 3.0 % (Sr) / < 5 %
Indicator lightYellow LED — on when detectingYellow LED — on when detecting
Protection ratingIP67 / IP68IP67 / IP68
Operating temperature−25 °C to +70 °C / −40 °C to +85 °C−25 °C to +70 °C / −40 °C to +85 °C
Storage temperature−40 °C to +85 °C−40 °C to +85 °C
Temperature drift< 10 % (Sr)< 10 % (Sr)
Short-circuit protectionYesYes
Reverse-polarity protectionYesYes
Overload protection point120 mA / 220 mA120 mA / 220 mA
Shell materialNickel-plated brass / Stainless steelNickel-plated brass / Stainless steel
Sensing-face materialABS / PBTABS / PBT
Standard wire length2 m (PVC cable)2 m (PVC cable)
Connection methodCable / M12 connectorCable / M12 connector
DimensionsM12 × 35 mm – 40 mmM12 × 45 mm – 50 mm
Weight≈ 40 g – 80 g≈ 50 g – 90 g
ComplianceRoHS · CE · ULRoHS · CE · UL
Vibration resistance10 – 55 Hz, 1 mm amplitude10 – 55 Hz, 1 mm amplitude
Shock resistance500 m/s², 10 times500 m/s², 10 times
Electromagnetic compatibilityIEC 61000 seriesIEC 61000 series

Technical Parameters

The M12 series technical parameters cover detection distance (depends on installation method, target material, and environmental factors; typical values are for standard iron targets, with correction factors for stainless steel 0.9, aluminum 0.4, brass 0.5, copper 0.4), supply voltage range (10 – 30 V DC, three-wire: brown = V+, blue = 0 V, black = output; some models support wider ranges), and output types (NPN or PNP open-collector, supporting NO, NC or NO+NC combinations).

The sensor supports high switching frequency up to 2000 Hz for high-speed applications, with response time < 0.5 ms. Protection features include short-circuit protection (auto-reset), reverse-polarity protection, overload protection (typical trigger 120 – 220 mA), and surge suppression. Environmental performance includes temperature drift < 10 % and repeatability within 3 – 5 %. Electromagnetic compatibility complies with IEC 61000 standards, ensuring strong anti-interference capability.

Working Principle

Inductive proximity sensors operate based on electromagnetic induction. An internal high-frequency oscillator drives an LC coil to generate an alternating electromagnetic field. When a conductive metal object enters this field, eddy currents are induced in the target, creating a counter-field that absorbs energy and changes the oscillator amplitude / frequency. The detection circuit (e.g. a Schmitt trigger) converts this change into a digital switching signal.

Flush (shielded) types concentrate the field at the sensing face and are suited for embedded mounting; non-flush (unshielded) types have a broader field and longer sensing distance but require greater side clearance.