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.
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 has an IP67 protection rating and is suitable for harsh industrial environments. The series is offered in three body lengths — 22 mm, 35 mm and 45 mm — each available in flush (“P”) or non-flush (“T”) mounting, with detection distances ranging from 2 mm to 10 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
| Parameter | M12 Flush Type | M12 Non-flush Type |
|---|---|---|
| Brand | DAIDISIKE | DAIDISIKE |
| Product name | M12 Metal Inductive Proximity Switch (Flush, “P”) | M12 Metal Inductive Proximity Switch (Non-flush, “T”) |
| Installation method | Flush (Shielded) | Non-flush (Unshielded) |
| Body lengths available | M12×1 × 22 mm / 35 mm / 45 mm | M12×1 × 28 mm (in the “22” short family) / 35 mm / 45 mm |
| Detection distance (standard iron target) | 2 mm / 4 mm (22 & 35 mm bodies); 2 / 4 / 6 mm (45 mm body) | 4 mm (22 & 35 mm bodies); 4 / 8 / 10 mm (45 mm body) |
| Output mode | NPN / PNP — NO (code 1) / NC (code 2) | NPN / PNP — NO (code 1) / NC (code 2) |
| Operating voltage | 10 – 30 V DC (three-wire) | 10 – 30 V DC (three-wire) |
| Maximum load current | 150 mA | 150 mA |
| No-load current | < 10 mA | < 10 mA |
| Voltage drop | < 1.5 V | < 1.5 V |
| Leakage current | < 0.01 mA | < 0.01 mA |
| Switching frequency | 1.5 kHz (2 mm) / 800 Hz (4 mm) on the 22 & 35 mm bodies; 1.5 kHz (2 mm) / 800 Hz (4 mm) / 600 Hz (6 mm) on the 45 mm body | 1 kHz (4 mm) on the 28 & 35 mm bodies; 1 kHz (4 mm) / 500 Hz (8 mm) / 100 Hz (10 mm) on the 45 mm body |
| Response time | 0.1 ms on the 22 & 35 mm bodies; 0.1 ms (2 mm) / 0.2 ms (4 mm) / 0.5 ms (6 mm) on the 45 mm body | 0.1 ms (28 mm body) / 0.2 ms (35 mm body); 0.2 ms (4 mm) / 0.5 ms (8 mm) / 1 ms (10 mm) on the 45 mm body |
| Switch hysteresis | < 15 % (Sr) | < 15 % (Sr) |
| Repeatability | < 3.0 % / < 5.0 % (Sr) | < 3.0 % / < 5.0 % (Sr) |
| Ripple | < 10 % | < 10 % |
| Indicator light | LED switching-state indicator | LED switching-state indicator |
| Protection rating | IP67 | IP67 |
| Operating temperature | −25 °C to +70 °C | −25 °C to +70 °C |
| Temperature drift | < 10 % (Sr) | < 10 % (Sr) |
| Short-circuit protection | Yes | Yes |
| Overload protection point | 180 mA | 180 mA |
| Shell material | Nickel-plated brass | Nickel-plated brass |
| Standard wire length | 2 m (longer on request) | 2 m (longer on request) |
| Connection method | Pre-wired cable | Pre-wired cable |
| Thread | M12 × 1 | M12 × 1 |
| Weight | Contact factory | Contact factory |
| Compliance / certification | Contact factory | Contact factory |
Technical Parameters
The M12 series technical parameters cover detection distance (depends on installation method, target material, and environmental factors; rated values are for a standard iron target, and non-ferrous metals such as stainless steel, aluminium, brass and copper reduce the achievable distance), supply voltage range (10 – 30 V DC, three-wire: brown = V+, blue = 0 V, black = output), and output types (NPN or PNP open-collector, in NO (code 1) or NC (code 2) switching logic).
The sensor supports switching frequencies from 100 Hz to 1.5 kHz with response times between 0.1 ms and 1 ms, depending on body length and rated sensing distance. Protection features include short-circuit protection and an overload current protection point of 180 mA. Environmental performance includes temperature drift < 10 % (Sr), switching hysteresis < 15 % (Sr), ripple < 10 % and repeatability within 3 – 5 % (Sr). Maximum load current is 150 mA with a no-load current below 10 mA and a voltage drop under 1.5 V.
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.
Frequently Asked Questions
What sensing distance does the M12 inductive proximity switch have?
Flush (shielded) versions detect a standard iron target at 2 mm or 4 mm, with 6 mm additionally available on the 45 mm body. Non-flush (unshielded) versions are rated 4 mm on the 22 mm and 35 mm bodies, and 4 / 8 / 10 mm on the 45 mm body. The rated Sn assumes a standard mild-steel target; non-ferrous metals such as stainless steel, brass, aluminium and copper reduce the achievable distance.
What is the difference between flush and non-flush M12 sensors?
Flush (shielded, “P” code) M12 sensors mount level with surrounding metal and resist side interference, but give a shorter range (2 / 4 / 6 mm). Non-flush (unshielded, “T” code) sensors need a metal-free clear zone around the sensing face and deliver a longer sensing distance (4 / 8 / 10 mm). Both are available in all three body lengths — 22, 35 and 45 mm.
Should I order NPN or PNP, and NO or NC output?
PNP (sourcing) 3-wire is the default for most modern PLCs, while NPN (sinking) is common in some Asian controls. Model code “1” is NO (output closes on detection) and “2” is NC (output opens on detection). Wire brown to V+, blue to 0 V and black to the PLC input. The M12 runs on 10–30 V DC three-wire.
Can the DAIDISIKE M12 replace an Omron, Balluff or Autonics M12 sensor?
Usually yes. It shares the M12 × 1 thread, DC 3-wire NPN/PNP wiring, IP67 rating and a 2–10 mm range, so it fits the same bracket and cable run. Match the flush / non-flush type, body length (22, 35 or 45 mm) and output (NPN/PNP, NO/NC) to the unit being replaced.
What ingress protection and temperature range does it have?
The DAIDISIKE M12 is rated IP67 with a nickel-plated brass housing and a −25 °C to +70 °C operating range. Short-circuit protection is built in with an overload current protection point of 180 mA, and every unit carries an LED switching-state indicator and a 2 m cable (longer on request).
How fast is the M12 proximity switch?
Response time ranges from 0.1 ms to 1 ms and switching frequency from 100 Hz to 1.5 kHz, depending on body length and rated sensing distance. The fastest combination — 22 mm flush body, 2 mm sensing distance — reaches 0.1 ms response and 1.5 kHz switching frequency.
Specs reviewed by Engineer Cai, Senior Application Engineer. Company CE & ISO approvals — see certificates.
Safety Light Curtain — Customer Cases
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