Omron D4NL-1DFA-B Safety Door Switch
Omron D4NL-1DFA-B is a 24 VDC guard lock safety door switch designed for interlocking protective doors and movable machine guards. It uses a mechanical lock with solenoid release and a 2NC + 2NC contact configuration for guard and lock status monitoring. A Type 2 low-level coded interlock supports mechanical guard detection, while IP67 protection supports industrial machine installations. The direct opening mechanism provides 60 N minimum force with 10 mm minimum travel, and an orange LED supports 10 to 115 VAC/VDC indication. The D4NL-1DFA-B belongs to the D4NL series within the guard lock safety switch range from Omron machine safety products.

| Brand | Omron |
| Product Type | Safety Door Switch |
| Model Number | D4NL-1DFA-B |
Omron D4NL-1DFA-B Safety Door Switch - Technical Specifications
| Specification | Value |
|---|---|
| Solenoid voltage/ indicator | Solenoid: 24 VDC, Orange LED: 10 to 115 VAC/VDC |
| Lock and release types | Mechanical lock Solenoid release |
| Contact configuration | 2NC+2NC |
| 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 | 60 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 100 m/s2 min. |
| Ambient operating temperature | −10 to 55°C |
| Ambient operating humidity | 95% max |
| Weight | Approx. 370 g |
The Omron D4NL-1DFA-B Guard Lock Safety Door Switch uses a Type 2 low-level coded interlock with IP67 enclosure protection for protective-door monitoring. Its 24 VDC solenoid works with a mechanical lock and solenoid release arrangement, while an orange LED supports 10 to 115 VAC/VDC indication. The 2NC + 2NC contact configuration provides switching for guard and lock status monitoring. Operating speed ranges from 0.05 to 0.5 m/s, and the direct opening mechanism provides 60 N minimum force with 10 mm minimum travel.
Electrical characteristics include 25 mΩ maximum contact resistance, a 300 V rated insulation voltage, 100 MΩ minimum insulation resistance and a 2 × 2 mm minimum contact gap. Rated frequency is 50/60 Hz. Malfunction vibration resistance covers 10 to 55 Hz at 0.75 mm single amplitude. Shock resistance reaches 1,000 m/s² minimum for destruction and 100 m/s² minimum for malfunction. The specified operating temperature extends from −10 to 55°C, ambient humidity is rated up to 95%. These specifications define its electrical, mechanical and environmental operating conditions for machine guard interlocking. For a related D4NL configuration with a 2NC/1NO + 1NC/1NO contact arrangement, the D4NL-1DFA-BS provides a closely related option.


