JNS18 & JNK18 Series M18 Diffuse Photoelectric Sensor

Name: JNS18 & JNK18 Series M18 Diffuse Photoelectric Sensor
Brand: DAIDISIKE
SKU: jns18-and-jnk18-series-m18-diffuse-photoelectric-sensor
Availability: InStock

M18 diffuse photoelectric sensors from 100 mm to 3 m, one-sided mounting, no reflector needed.

JNS18 & JNK18 Series M18 Diffuse Photoelectric Sensor - product photo

🔍 Click to enlarge · 1/18

Technical Specifications

Model	JNS18-10/30/50 D(N1/P1/N2/P2) (12 models); JNK18-30/50/100/300 D(N1/P1/N2/P2) (16 models)
Output Type	DN1=NPN NO, DP1=PNP NO, DN2=NPN NC, DP2=PNP NC (JNK18's DN2/DP2 are complementary N.O.+N.C.)
Sensing Mode	Diffuse reflective
Sensing Distance (JNS18)	10 cm / 30 cm / 50 cm
Sensing Distance (JNK18)	30 cm / 50 cm / 1 m / 3 m
Housing / Thread	JNS18: M18×68 mm, plastic housing; JNK18: M18×73 mm
Supply Voltage	10-30 VDC
Protection Rating	IP65
Overload Protection	JNK18: 300 mA

Overview

JNS18 and JNK18 are diffuse-reflective (proximity-mode) photoelectric sensors housed in a standard M18 cylindrical barrel. JNS18 is the short-range, plastic-housing model (M18×68 mm) covering 10/30/50 cm; JNK18 is the long-range model (M18×73 mm) covering 30 cm/50 cm/1 m/3 m, with built-in output overload protection.

They are intended for machine builders, panel integrators, and OEMs who need to detect the presence of an object — carton, pallet, sheet, part, or bulk material — from one side, without installing a reflector or a separate receiver on the other side of the detection path. Together the two series offer seven sensing-range options and a choice of NPN/PNP, normally-open/normally-closed output on every model.

Features & Benefits

Up to 3 m diffuse sensing range in a standard M18 barrel

JNK18-300D reaches 3 m detection distance using pure diffuse reflection, so only one side of the line needs mounting and wiring. No reflector or receiver is required on the opposite side.

Seven range-and-series options (five distinct sensing distances) from 100 mm to 3 m

JNS18 offers 10/30/50 cm and JNK18 offers 30 cm/50 cm/1 m/3 m — five distinct distance values across the two series — so the range can be matched precisely to the application instead of over- or under-specifying.

Complementary N.O. + N.C. dual output on JNK18 DN2/DP2

The DN2 (NPN) and DP2 (PNP) variants of JNK18 output both normally-open and normally-closed signals simultaneously from a single sensor body, so one unit can drive two logic states without occupying two mounting positions.

Selectable NPN/PNP and N.O./N.C. output on every model

Each series is offered in four output codes (DN1=NPN N.O., DP1=PNP N.O., DN2/DP2), matching common PLC input card conventions (sinking or sourcing) without needing external relays.

Standard M18 threaded cylindrical housing

The M18 thread is a widely used barrel-sensor mounting standard, so the sensor installs into existing M18-diameter mounting holes with a simple nut fixing. Housing length is M18×68 mm for JNS18 and M18×73 mm for JNK18 — check length and optical-axis position before replacing an existing sensor.

Built-in output overload protection on JNK18 (300 mA)

Protects the output stage from wiring faults or excessive load current during commissioning, reducing the risk of sensor damage from installation-stage mistakes.

IP65-rated housing

Sealed against dust ingress and low-pressure water jets from any direction, suited to general industrial and outdoor-adjacent installation environments.

Wide-range 10-30 VDC supply

Compatible with the standard 24 VDC control-panel supply rail used across most industrial automation systems, with tolerance for typical line variation.

Applications

Carton / pallet / bag presence detection on conveyor lines — Single-sided installation with long-range diffuse sensing (JNK18 up to 3 m) can cover a wide conveyor belt without mounting a reflector or receiver on the opposite side.

Storage rack / pallet-position occupancy sensing — Long-range models (50 cm-3 m) can be mounted at the back of a rack position to detect whether the position is occupied.

Roller conveyor part/object detection — Multiple range options match the actual width and mounting position requirements of roller conveyor lines.

General near-range part-in-place detection at a workstation — The JNS18 economy plastic-housing series covers 10/30/50 cm, suited to routine workstation detection at lower cost.

Wide-area object detection in agricultural or logistics equipment — The JNK18-300D's 3 m sensing distance suits equipment with larger spaces or where one-sided mounting is the only option.

PLC dual-state feedback from a single sensor position — JNK18's DN2/DP2 complementary N.O.+N.C. output delivers both a 'present' and an 'absent' signal from one sensor, avoiding a second sensor installation.

Sinking or sourcing PLC input matching — Each series is offered in both NPN and PNP output models to match sinking (NPN) or sourcing (PNP) PLC input cards.

Models & Ordering Information

JNS18 Series — M18×68 mm plastic housing, 10/30/50 cm (12 models)

JNS18-10DN1JNS18-10DP1JNS18-10DN2JNS18-10DP2JNS18-30DN1JNS18-30DP1JNS18-30DN2JNS18-30DP2JNS18-50DN1JNS18-50DP1JNS18-50DN2JNS18-50DP2

DN1=NPN N.O., DP1=PNP N.O., DN2=NPN N.C., DP2=PNP N.C.

JNK18 Series — M18×73 mm long-range, 30 cm/50 cm/1 m/3 m, with output overload protection (16 models)

JNK18-30DN1JNK18-30DP1JNK18-30DN2JNK18-30DP2JNK18-50DN1JNK18-50DP1JNK18-50DN2JNK18-50DP2JNK18-100DN1JNK18-100DP1JNK18-100DN2JNK18-100DP2JNK18-300DN1JNK18-300DP1JNK18-300DN2JNK18-300DP2

DN1=NPN N.O., DP1=PNP N.O., DN2=NPN complementary N.O.+N.C., DP2=PNP complementary N.O.+N.C. (definition of DN2/DP2 differs from JNS18 — confirm before ordering).

How to Select

Need 10 cm, 30 cm, or 50 cm near/mid-range detection: choose the JNS18 series (economy plastic housing).
Need 30 cm, 50 cm, 1 m, or 3 m mid/long-range detection, or need output overload protection: choose the JNK18 series.
Both 30 cm and 50 cm are available in both series — choose JNS18 if budget is the priority, or JNK18 if overload protection or a longer housing is needed.
If your PLC input is sinking (NPN), choose a DN1 (single N.O.) or DN2 model; if sourcing (PNP), choose a DP1 (single N.O.) or DP2 model.
The DN2/DP2 definition differs between series: on JNS18, DN2/DP2 are single normally-closed outputs; on JNK18, DN2/DP2 output normally-open and normally-closed simultaneously. Confirm this before ordering or wiring.
Need only a single normally-open signal (output when object present): choose a '1' suffix model (DN1/DP1).
Need only a single normally-closed signal (JNS18 only): choose a JNS18 '2' suffix model (DN2/DP2).
Need both normally-open and normally-closed signals from one sensor: choose a JNK18 '2' suffix model (DN2/DP2, dual output).
JNS18 housing is M18×68 mm plastic; JNK18 housing is M18×73 mm. Both use standard M18 mounting threads and a nut fixing — check housing length and optical-axis position before replacing an existing sensor.
Both series share a 10-30 VDC supply and IP65 rating, suitable for general industrial environments without additional consideration.

📘 Need the full method? NPN vs PNP Sensor Outputs Explained

When NOT to specify the JNS18 — and what to use instead

Dark, matte, or low-reflectivity targets, especially near the top of the JNK18's 3 m range

Why not: All JNS18/JNK18 models are diffuse-reflective, sensing light reflected from the target itself, so a low-reflectivity target will trigger at a shorter distance than the rated 10cm-3m figures.

Use instead: a through-beam pair for long range that doesn't depend on target reflectivity

Detection distance beyond 3 m

Why not: The longest rated range in the line-up is the JNK18-300D at 3 m; no model in this series exceeds that.

Use instead: a through-beam pair rated for longer range (up to 15 m)

The target is a clear film or transparent sheet

Why not: Diffuse-reflective sensing depends on light reflected back from the target surface, which a transparent target may not return reliably.

Use instead: a through-beam pair for color/transparency-independent detection

Personnel guarding or a safety interlock

Why not: No safety rating is documented; this is a general industrial presence sensor.

Use instead: a safety-rated light curtain or safety interlock

Specifications we do not publish yet

We only publish a figure once we are confident it is true. The items below are still being validated through further testing and real-world customer feedback, so for now we would rather leave them open than guess. If one of them matters to your design, ask us for the latest validated status.

Response time (operate/reset)
Hysteresis
Minimum detectable object size
Operating and storage temperature range
MTBF or expected service life
Whether the stated sensing distances (10/30/50cm etc.) are fixed or adjustable within each model
Certification documentation beyond 'available on request'

Frequently Asked Questions

What is the difference between JNS18 and JNK18?

JNS18 is the shorter-range, plastic-housing model (M18×68 mm) covering 10/30/50 cm sensing distances. JNK18 is the longer-range model (M18×73 mm) covering 30 cm/50 cm/1 m/3 m, and it includes built-in 300 mA output overload protection that JNS18 does not have.

Do these sensors need a reflector or a separate receiver?

No. Both JNS18 and JNK18 are diffuse-reflective sensors — they emit light and detect the amount reflected back from the target object itself, so they only need to be mounted on one side of the detection path with no reflector or receiver on the opposite side.

What output types are available?

Each model is offered in four output codes: DN1 (NPN, normally open), DP1 (PNP, normally open), DN2 and DP2. On JNS18, DN2/DP2 are single normally-closed outputs (NPN/PNP respectively). On JNK18, DN2/DP2 output both normally-open and normally-closed states simultaneously (complementary dual output).

What is the sensing distance range?

JNS18 offers 10 cm, 30 cm, or 50 cm. JNK18 offers 30 cm, 50 cm, 1 m, or 3 m. In total there are five distinct rated sensing distances across the two series.

What supply voltage do these sensors require?

10-30 VDC, compatible with standard 24 VDC industrial control-panel supplies.

What is the ingress protection rating?

IP65 — protected against dust ingress and low-pressure water jets from any direction.

Does JNK18 have overload protection?

Yes. JNK18 includes built-in output overload protection rated at 300 mA, which helps protect the sensor's output stage from wiring faults or excessive load during commissioning. This feature is documented for JNK18; it is not listed for JNS18.

Can JNK18 replace an existing M18 diffuse sensor from another brand without any mechanical modification?

The M18 thread itself is a common mounting standard and will fit existing M18 mounting holes, but housing length (M18×73 mm for JNK18, M18×68 mm for JNS18) and optical-axis position have not been cross-checked against other brands' dimensions in our documentation. Confirm length and optical-axis alignment before treating this as a drop-in replacement.

What certifications do these sensors carry?

Certification documents are available on request.