Omron D4NS-4FF Safety Door Switch
Omron D4NS-4FF is a 1-conduit safety door switch with an M20 connection and slow-action MBB 2NC/1NO contacts for protective machine guard monitoring. The MBB contact arrangement provides overlapping switching, while the normally closed and normally open contacts support guard status within the machine safety circuit. A Type 2 low-level coded interlock provides mechanical guard-position detection, and IP67 protection suits industrial installations. Direct opening force is 60 N minimum for standard types and 80 N minimum for high pull-force types, with 10 mm minimum travel. The D4NS-4FF belongs to the D4NS series within the machine safety door switch range from Omron industrial safety products, supporting protective access and guard-position monitoring.

| Brand | Omron |
| Product Type | Safety Door Switch |
| Model Number | D4NS-4FF |
Omron D4NS-4FF Safety Door Switch - Technical Specifications
| Specification | Value |
|---|---|
| Type | 1-Conduit type |
| Contact configuration | Slow-action MBB contact,2NC/1NO |
| Conduit outlet/Connector | M20 |
| Interlock type | Type 2 |
| Coding level | Low level coded |
| Degree of protection | IP67 |
| Operating speed | 0.05 to 0.5 m/s |
| Direct opening force | <Standard type> 60 N min.; <High pull-force type> 80 N min. |
| Direct opening travel | 10 mm min. |
| Contact resistance | 25 mΩ max. |
| Rated insulation voltage (Ui) | 300 V |
| Rated frequency | 50/60 Hz |
| Insulation resistance | 100 MΩ min. |
| Contact gap | 2 × 2 mm min |
| Vibration resistance | Malfunction: 10 to 55 Hz, 0.75 mm single amplitude |
| Shock resistance | Destruction: 1,000 m/s2 min. Malfunction: 300 m/s2 min |
| Ambient operating temperature | −30 to 70°C (with no icing) |
| Ambient operating humidity | 95% max |
| Weight | Approx. 96 g |
The Omron D4NS-4FF Safety Door Switch combines a 1-conduit M20 connection with slow-action MBB 2NC/1NO contacts for protective machine guard monitoring. The MBB contact system provides overlapping switching, while the 2NC/1NO arrangement offers normally closed safety paths together with a normally open status path. A Type 2 low-level coded interlock provides mechanical guard-position detection, and IP67 enclosure protection supports industrial machine safety installations.
The direct opening mechanism provides 60 N minimum force for standard types and 80 N minimum for high pull-force types, with 10 mm minimum travel. Operating speed ranges from 0.05 to 0.5 m/s. The key relationships for this model are MBB switching, 2NC/1NO contacts, M20 wiring, direct opening and protective-door monitoring. Together, these attributes connect the D4NS-4FF with safety door switches, machine guards, interlock systems and safety control circuits. Its 1-conduit construction differentiates it from D4NS variants using dual conduit entries, while the MBB contact arrangement distinguishes it from conventional slow-action contact versions. This gives the page useful model-specific context without depending on weight, vibration or other secondary specifications. For a D4NS model using the same MBB 2NC/1NO contact arrangement and M20 format but with a 2-conduit construction, the D4NS-8CF provides a closely related configuration.


