Omron D4A-3109N Limit Switch
Omron D4A-3109N is a general-purpose limit switch with a stainless steel top plunger and snap-action mechanism for direct machine position detection. The straight actuator suits stops, slides, and moving parts that approach the switch head-on, while the SPST-NO/SPST-NC contact arrangement provides separate switching paths for control circuits. High inrush capability supports general loads, and IP67 with multiple NEMA enclosure ratings supports protected machine installations. The D4A-3109N belongs to the D4A Series within the top plunger limit switch range from Omron industrial control products for direct travel, position, and end-of-stroke sensing with top-plunger actuation and defined snap-action switching for repeated machine cycles.
| Brand | Omron |
| Product | Limit Switch |
| Model Number | D4A-3109N |
Omron D4A-3109N Limit Switch – Technical Specifications
| Specification | Value |
|---|---|
| Shape Structure | General-purpose Limit switches |
| Ctuator | Top plunger Stainless steel plunger Standard |
| Contact Form | SPST-NO/SPST-NC |
| Load | General load |
| Inrush Current | NC: 30 A max. NO: 20 A max. |
| Ambient Temperature | Operating: -20 to 100 ℃ |
| Ambient Humidity | 35 to 95% RH |
| Shock Resistance | Destruction: 1,000 m/s 2 max. |
| Degree Of Protection | IP67 NEMA Type1, 2, 3, 4, 4X, 5, 6P, 12, 13 |
| Contact Resistance Initial Value | 25 mΩ max. |
| Durability | Electrical: 1,000,000 operations min. (10 A at 125 VAC ) |
| Vibration Resistance | Malfunction: 10 to 55 Hz, 1.5 mm double amplitude |
| Operating Mechanism | Snap action |
The Omron D4A-3109N Limit Switch uses a stainless steel top plunger with a snap-action mechanism for direct machine position and end-of-travel detection. The straight actuator suits stops, slides, and moving parts that approach the switch head-on, while snap-action operation provides a defined switching response. Its SPST-NO/SPST-NC contact arrangement gives separate normally open and normally closed paths for control circuits. Inrush current capability reaches 30 A maximum on the NC side and 20 A maximum on the NO side. IP67 protection together with multiple NEMA enclosure ratings supports protected machine installations.
Electrical durability is specified at 1 million operations minimum at 10 A, 125 VAC, supporting repeated general-load switching. Initial contact resistance is 25 mΩ maximum. The D4A-3109N operates from -20 to 100°C with 35 to 95% relative humidity. Destructive shock resistance reaches 1,000 m/s² maximum, while malfunction vibration resistance covers 10 to 55 Hz at 1.5 mm double amplitude. These characteristics suit direct top-plunger position sensing where snap-action response, general-load capability, and separate NO/NC switching paths are required. The top plunger is especially useful where the target moves directly toward the actuator rather than across it. For a related D4A model using a vertical side roller plunger, see the D4A-3107-VN model.
