Omron D4NL-4HFG-B Safety Door Switch
Omron D4NL-4HFG-B is a 24 VDC guard lock safety door switch designed for protective-door monitoring and controlled machine access. It uses a solenoid lock with mechanical release, while the 3NC + 2NC contact configuration provides multiple normally closed switching paths for guard and lock status monitoring. An M20 conduit supports machine wiring, and a Type 2 low-level coded interlock provides mechanical guard-position detection. IP67 protection supports industrial safety installations, while the direct opening mechanism provides 60 N minimum force with 10 mm minimum travel. The D4NL-4HFG-B belongs to the D4NL series within the guard lock safety switch range from Omron industrial safety products, supporting machine guards and protective access control.

| Brand | Omron |
| Product Type | Safety Door Switch |
| Model Number | D4NL-4HFG-B |
Omron D4NL-4HFG-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 | Solenoid lock Mechanical release |
| Contact configuration | 3NC+2NC |
| 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-4HFG-B Guard Lock Safety Door Switch combines a 24 VDC solenoid lock with mechanical release for protective machine access control. Its 3NC + 2NC contact configuration provides multiple normally closed switching paths for monitoring guard and lock conditions. An M20 conduit provides the wiring entry, while the Type 2 low-level coded interlock supports mechanical guard-position detection. IP67 enclosure protection supports industrial machine safety installations where the switch may encounter dust or moisture during operation.
The direct opening mechanism provides 60 N minimum force with 10 mm minimum travel, and the switch supports guard movement from 0.05 to 0.5 m/s. An orange LED supports 10 to 115 VAC/VDC indication for visual status information. The 3NC + 2NC contact arrangement is an important differentiating attribute when comparing this model with other D4NL guard lock switches. Combined with solenoid locking, mechanical release and M20 wiring, it establishes clear relationships with protective doors, machine guards, controlled access and safety circuit monitoring. These functional entities are more useful for product relevance than adding secondary specifications that do not help distinguish the model. The switch therefore fits applications requiring guard locking together with multiple normally closed monitoring paths. For an M20 D4NL model with the same solenoid lock and mechanical release principle but a 2NC/1NO + 2NC contact arrangement, the D4NL-4FFG-B provides a related configuration.


