Omron D4NL-4AFA-B Safety Door Switch
Omron D4NL-4AFA-B is a 24 VDC guard lock safety switch with an M20 conduit outlet for protective-door interlocking on industrial machinery. It combines a mechanical lock with solenoid release and a 1NC/1NO + 1NC/1NO contact configuration for monitoring guard and lock status. Its Type 2 low-level coded interlock supports controlled machine access, while IP67 enclosure protection supports industrial installations. The switch also includes an orange LED rated for 10 to 115 VAC/VDC and a direct opening mechanism with 60 N minimum force. The D4NL-4AFA-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-4AFA-B |
Omron D4NL-4AFA-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 | 1NC/1NO+1NC/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 | 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-4AFA-B Guard Lock Safety Switch uses a Type 2 low-level coded interlock and provides IP67 enclosure protection. It supports operating speeds from 0.05 to 0.5 m/s, while its direct opening mechanism provides 60 N minimum force with 10 mm minimum opening travel. The mechanical lock uses solenoid release, and an orange LED is rated for 10 to 115 VAC/VDC. Its 1NC/1NO + 1NC/1NO contact configuration provides separate switching functions for monitoring the protective guard and lock condition.
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 is specified at 1,000 m/s² minimum for destruction and 100 m/s² minimum for malfunction. The ambient operating temperature ranges from −10 to 55°C, with humidity up to 95%. An M20 conduit outlet provides the connection arrangement. For an M20 D4NL model using the same 24 VDC solenoid and mechanical-lock/solenoid-release principle but a different 2NC + 1NC/1NO contact arrangement, see the D4NL-4CFA-B.


