Leuze KRTM 55/4.1121-S8 Contrast Sensor
Leuze KRTM 55/4.1121-S8 contrast sensor delivers 13 mm operating range, RGB LED light, and PNP transistor output switching control. Manufactured by Leuze, this Leuze Contrast Sensor belongs to the KRT Series and supports 13 mm ± 2 mm operating range, PNP light/dark switchable output, 10,000 Hz switching frequency, M8 connector interface, teach button operation, and IP67/IP69K protection.
| Brand | Leuze |
| Product Type | Contrast Sensor |
| Product | KRTM 55/4.1121-S8 |
Leuze KRTM 55/4.1121-S8 Contrast Sensor – Technical Specifications
| Specification | Value |
|---|---|
| Design | Cubic |
| Dimension (W x H x L) | 14 mm x 35.5 mm x 25 mm |
| Special version | Teach input Time function |
| Operating range | 13 mm ± 2 mm |
| Beam path | Focused |
| Light Source | LED, RGB |
| Light spot size [at sensor distance] | 1.5 mm x 6.5 mm |
| Light spot orientation | Vertical |
| Type of light spot geometry | Rectangular |
| Light beam exit | Front |
| Wavelength | - |
| Supply voltage UB | 10 ... 30 V, DC |
| Number of teach inputs | 1 Piece(s) |
| Number of digital switching outputs | 1 Piece(s) |
| Switching output | Transistor, PNP |
| Switching principle | Light/dark switchable |
| Switching frequency | 10,000 Hz |
| Response time | - |
| Con:1 Function | - |
| Type of connection | Connector |
| Thread size | M8 |
| Type | - |
| Material | Stainless steel |
| No. of pins | 4-pin |
| Housing material | Stainless steel |
| Housing color | - |
| Type of fastening | - |
| Type of display | LED |
| Operational controls | Teach button |
| Ambient temperature, operation | -30 ... 55 °C |
| Ambient temperature, storage | - |
| Degree of protection | IP 67 IP 69K |
The KRTM 55/4.1121-S8 Leuze Transistor PNP Light/Dark Switchable Contrast Sensor is designed for precise optical contrast detection in industrial automation systems. The KRTM 55/4.1121-S8 operates with a 13 mm operating range, RGB LED light source, PNP transistor output, and 10,000 Hz switching frequency. It belongs to the KRT Series and is used where compact, accurate contrast sensing is required.
This contrast sensor is applied in conveyors, packaging machines, labeling systems, and automated assembly lines. Its focused beam path and rectangular light spot support stable detection of marks and print contrasts at high speeds. The stainless steel housing and teach-button controls allow reliable setup and operation in space-constrained industrial environments.
The KRTM 55/4.1121-S8 reflects Leuze’s emphasis on reliable sensing performance and mechanical durability. With IP67/IP69K protection, stable electrical switching, and compact construction, it is suitable for continuous industrial use. As part of the Leuze KRT Series, it delivers consistent contrast detection for demanding automation applications.

