Siemens 3SE51220BE01 Steel Roller Lever Limit Switch
Product placement and core function
The 3SE51220BE01 is a Siemens chassis-mount limit switch used in industrial position-sensing and end-of-travel detection circuits. It combines a steel roller lever actuator with a DPST-NO/NC contact block to signal machine states to upstream controls.
Catalog parameters
| Parameter | Value |
|---|---|
| Actuator Type | Lever, Roller |
| Circuit | DPST-NO/NC |
| Current Rating | 6A (AC), 550mA (DC) |
| Electrical Life | 100,000 Cycles |
| Mechanical Life | 15,000,000 Cycles |
| Operating Force | 1020gf |
| Ingress Protection | IP66/IP67 |
| Mounting Type | Chassis Mount |
| Base Product Number | 3SE5122 |
| Encapsulation | Bulk |
Actuator and contact configuration
The steel roller lever actuator targets side-entry or cam-driven actuation paths where the driven element contacts the roller at a known approach angle. Operating force is specified at 1020gf, placing it in the mid-range for Siemens 3SE5-series lever variants. The contact arrangement provides one normally open and one normally closed pole, enabling complementary state reporting without requiring separate switch bodies.
Environmental sealing
Ingress protection is rated IP66/IP67, covering dust-tight sealing and temporary water immersion. This rating is consistent across the 3SE5122 series and supports deployment in washdown-prone areas or outdoor enclosures.
In-catalog comparison parts
The 3SE5122 base number spans multiple actuator configurations. Comparison screening below lists shared spec keys only.
| Spec | 3SE51220BE01 (seed) | 3SE51220BF01 | 3SE51220BH01 |
|---|---|---|---|
| Actuator Type | Lever, Roller | Top Rotary, Roller | Side Rotary, Roller |
| Current Rating (AC) | 6A | 6A | 6A |
| Current Rating (DC) | 550mA | 3A | 3A |
| Operating Force | 1020gf | 1020gf | — |
| IP Rating | IP66/IP67 | IP66/IP67 | IP66/IP67 |
| Mechanical Life | 15,000,000 | 15,000,000 | 15,000,000 |
| Circuit | DPST-NO/NC | DPST-NO/NC | DPST-NO/NC |
| Similarity | — | 1.0 | 1.0 |
All listed parts require reader qualification before use as alternatives.
3SE51220BF01 shares the same roller lever family, identical operating force, and matching AC current rating; it differs by using a top rotary lever orientation and lists 3A DC current rating.
3SE51220BH01 shares the IP66/IP67 rating and 6A AC rating but uses a side rotary crank lever and does not list operating force in the catalog record.