Omron VB-3221 Limit Switch
Omron VB-3221 is a multiple limit switch with three roller plungers, each using a 6.8 mm roller for smooth multi-point position detection. The three-plunger arrangement allows several machine positions to be monitored from one housing, while flange mounting provides a stable installation base and four cable-entry directions add wiring flexibility. Operating speed ranges from 0.1 mm/s to 0.5 m/s, and IP67 protection supports repeated use around dust, water, or oil exposure. The VB-3221 belongs to the VB Series within the multiple roller plunger switch range from Omron automation products for coordinated machine position and sequence detection across conveyors, transfer systems, and indexing mechanisms.
| Brand | Omron |
| Product | Limit Switch |
| Model Number | VB-3221 |
Omron VB-3221 Limit Switch – Technical Specifications
| Specification | Value |
|---|---|
| Number Of Plungers | 3 plungers |
| Shape Of Box | With flange |
| Conduit | Four |
| Ambient Temperature | –10°C to 80°C (with no icing) |
| Ambient Humidity | 35% to 95% |
| Shock Resistance | Destruction: 1,000 m/s2 min. Malfunction: 200 m/s2 min. |
| Degree Of Protection | IP67 |
| Durability | Mechanical: 5,000,000 operations min. Electrical: 300,000 operations min. (10 A at 250 VAC, resistive load) |
| Insulation Resistance | 100 MΩ min. (at 500 VDC) |
| Actuator | Roller plunger (with a 6.8-dia. roller) |
| Vibration Resistance | Malfunction: 10 to 55 Hz, 1.5-mm double amplitude |
| Operating Speed | 0.1 mm to 0.5 m/s |
| Operating Frequency | Mechanical: 120 operations min. Electrical: 30 operations min. |
| Contact Resistance | 15 mΩ max. (initial value) |
| Rated Insulation Voltage Ui | 300 VAC |
| Rated Frequency | 50/60 Hz (AC) |
| Weight | Approx. 580 g |
The Omron VB-3221 Limit Switch uses three roller plungers, each with a 6.8 mm roller, for coordinated multi-point position detection. The roller contact supports smooth actuation from moving parts, while flange mounting provides a stable installation base. Four cable-entry directions give added flexibility when routing wiring around panels or machine frames. Operating speed ranges from 0.1 mm/s to 0.5 m/s, with up to 120 mechanical and 30 electrical operations per minute. IP67 protection supports use around dust, water, or oil, and the operating temperature range extends from -10 to 80°C.
Mechanical durability is specified at 5 million operations minimum, while electrical durability reaches 300,000 operations minimum at 10 A, 250 VAC resistive load. Initial contact resistance is 15 mΩ maximum, and insulation resistance is 100 MΩ minimum at 500 VDC. The VB-3221 withstands destructive shock of at least 1,000 m/s² and malfunction shock of at least 200 m/s². Malfunction vibration resistance covers 10 to 55 Hz at 1.5 mm double amplitude. These characteristics suit multi-point travel and sequence detection where flange mounting and four wiring directions are useful. The flange base also helps keep the switch position consistent during repeated mechanical actuation. For another three-roller-plunger VB model with a no-flange mounting format, see the VB-3251 model.
