Schmersal T.250-11z-t Limit Switch

The Schmersal T.250-11z-t is a heavy-duty limit switch designed for industrial position sensing and safety applications. It features a roller lever actuator (adjustable) and a snap-action switching element with one normally open (NO) and one normally closed (NC) contact (1NO+1NC). The switch is housed in a robust metal enclosure rated IP67, making it suitable for harsh environments such as machine tools, conveyors, and material handling equipment.

Switching Specifications

• Contact configuration: 1 NO + 1 NC (slow action or snap action – snap action in this model).

• Rated thermal current (Ith): 10 A (at 250V AC).

• Rated insulation voltage (Ui): 300 V AC.

• Contact material: silver alloy (AgCdO).

• Mechanical life: 10 million operations minimum.

• Electrical life: 1 million operations at rated load.

Actuator and Operation

The T.250-11z-t is equipped with a roller lever (plastic roller, diameter 18 mm) with a lever length of 50 mm (adjustable ±30°). The actuator is spring-returned. Operating force: 8 N (typical). Pretravel: 15°; overtravel: 75°; differential travel: 4°. The switch is designed for position detection of cams, slides, and other moving machine parts.

Enclosure and Protection

Enclosure material: die-cast aluminum with a corrosion-resistant powder coating (RAL 7035). The cover is secured with M4 screws and includes a sealing gasket. Protection class: IP67 (dust-tight and protected against temporary immersion). Cable entry: two M20 x 1.5 metric threaded entries (top and bottom). The switch is rated for ambient temperature -25°C to +80°C.

Electrical Connection

Terminals: screw-type (M3.5) inside a terminal chamber, accepting wire up to 2.5 mm² (AWG 14). The switch is supplied without cable; the user must provide suitable cable glands. A grounding terminal is provided inside the enclosure for safety earth connection.

Standards and Certifications

The limit switch meets IEC 60947-5-1, EN 60204-1, and UL 508. It is CE marked and RoHS compliant. The switch is not a safety-rated device (not suitable for emergency stop without additional redundancy). However, it can be used in control circuits up to category 1 (EN ISO 13849-1).

Dimensions and Mounting

Overall dimensions: 40 mm width x 72 mm height x 100 mm depth (excluding actuator). Mounting: two M5 screws on a 30 mm x 60 mm pattern (or using slotted holes). Weight: 0.35 kg. The actuator can be rotated in 90° increments to adjust direction.

Typical Applications

End-of-travel detection for linear slides, conveyor belt monitoring, valve position feedback, and packaging machine cycle verification.

Ordering and Documentation

Schmersal part number: T.250-11z-t. The switch is supplied with a wiring diagram label and two M20 blanking plugs. Manual: Schmersal T.250 Series Data Sheet (101040-EN).