Inductive · square block, front or top sensing

Square-Type Inductive Proximity Sensors (5 × 5 to 17 × 17 mm)

A block instead of a barrel, with the sensing face on the front or on the top — the shape that fits against a flat plate, inside a channel, or under a moving

Model LJQ5M / LJQ8M / LJQ10M / LJQ17M · Brand LE Raun · Category: Proximity Sensors

Body5×5 – 17×17 mm

Sensing1 – 8 mm

FaceFront or top

Response0.2 – 0.3 ms

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Overview

A square body solves a mounting problem a barrel cannot: it sits flat on a plate, needs two bolts instead of a bracket, and can present its face sideways or upwards. That is why these sensors end up on tracks, slides, magazines and sheet lines rather than on cylinders.Sensing distances run 1 mm on the 5×5 block to 8 mm on the 17×17, all with an adjustable setting distance so a thin film or a paint layer can be tuned out. Response time is 0.2 – 0.3 ms, faster than the barrel families with the same range.Ambient range is −25 °C to +70 °C, output NPN or PNP, NO or NC, 10 – 30 V DC. Bodies are moulded with the cable exiting the end or the side depending on the size.

Application scenarios

Part on a linear track

A 5×5 mm block mounts in the track wall with the face on top and sees small parts passing over it.

Slide and carriage end position

The 17×17 block bolts to the carriage and reads a target plate at 8 mm, surviving the impact that would shear a barrel.

Tool-present check in a magazine

The 10×6 block sits between two tool pockets and confirms the tool is seated, with the cable running in the existing channel.

Cam and stopper detection

0.2 ms response catches a stopper that is only in position for a few milliseconds.

Metal sheet edge on a cut-to-length line

Top-sensing block under the sheet detects the leading edge without the sensor standing in the sheet path.

Industries

General machinery
Electronics assembly
Metalworking
Packaging

Technical specifications

Series	LJQ5M · LJQ8M · LJQ10M · LJQ17M
Body sizes	5×5×23 · 8×8×24 / 25 · 10×6×27 · 17×17×28 mm
Sensing distance	1 – 8 mm ±10 %, adjustable setting distance
Sensing face	Front-side or top-side, depending on model
Sensing object	Magnetic metal
Operating voltage	10 – 30 V DC
Response time	0.2 ms (0.3 ms on the 8 mm version)
Switching frequency	1 kHz (500 Hz on the 8 mm version)
Ambient temperature	−25 °C – +70 °C
Output	NPN / PNP, NO / NC — N, N2, P, P2 suffix
Protection	IP67
Current consumption	≤10 mA
Output current	≤200 mA
Voltage drop	≤1.5 V
Repeat accuracy	≤0.05 mm
Circuit protection	Short-circuit, overload, reverse polarity
Cable	2 m PVC, 3 × 0.2 mm², oil-resistant

Dimensions

Item	Value
Mounting holes	Ø3.2 mm through-holes, 2 off, on the body centre line
Cable	2 m, 3-core

The 18 × 10 × 30.5 mm body is the flat one for a narrow slot; the 17 × 17 mm and 18 × 18 mm bodies share the same 3.2 mm mounting pattern.

Wiring & output

Lead	Colour
2	Blue
3	Black
—	Two-wire types

How to specify

01
Choose shielded or unshielded
A shielded (flush) sensor can be embedded in metal with only its face exposed, at about 60 % of the unshielded range. An unshielded sensor needs a free zone around the barrel but reaches further.
02
Size the sensing distance
Order at least 1.5 × the nominal distance to allow for tolerances, temperature and target material. Non-ferrous targets — brass, aluminium, copper, stainless — reduce the distance to roughly 30–50 %.
03
Match the target size
The target should be at least as large as the sensing face. A smaller target reduces the distance proportionally, so a 4 mm target on an M18 sensor will not switch at 5 mm.
04
Pick the output and the body
NPN / PNP, NO / NC, 3-wire or 2-wire. Plastic barrel for general use, stainless for weld fields, PTFE-faced for weld spatter, high-temperature types up to 120 °C.

Why this series

Front or top face, same block

Two versions of each size: face on the end (front-side) for a part arriving along the block, face on the top for a part sliding over it.

0.2 ms response

Fast enough for a small part on a high-speed track, where a 45 mm barrel with a 1.5 ms response would miss it.

Adjustable setting distance

The pot lets you set the trip point below the maximum, which is how you ignore a thin film and still see the part behind it.

Bolt-down, no bracket

Two through-holes in the block let it sit flat against a plate — no right-angle bracket to work loose.

Questions

Front-side or top-side sensing?

Front-side if the part approaches along the length of the block (end of a track). Top-side if the part passes over the block (sheet, slide, conveyor).

What does 'adjustable setting distance' mean?

A potentiometer sets the trip point below the maximum range, so you can ignore a 0.5 mm film and still detect the 3 mm part behind it.

Can it detect aluminium?

These are inductive and specified for magnetic metal — mild steel is the reference. Aluminium reduces the range substantially; for aluminium use a capacitive or photoelectric sensor.

Need a quotation for Square-Type Inductive?

Send your application details or the guard opening dimensions and we will specify the right model and configuration for your machine.