Phoenix REL-MR- 24DC/21 Single Relay
The Phoenix REL-MR- 24DC/21 Single Relay (Part No: 2961105 ) offers a 24 V DCnominal input voltage UN, 14.4 V DC ... 66 V DC input voltage range, 250 V AC/DC switching voltage, Plug / solder connection method. Manufactured by Phoenix under the Phoenix Single Relay category, this model belongs to the Phoenix REL Series.

| Brand | Phoenix Contact |
| Product Type | Single Relay |
| Model Number | REL-MR- 24DC/21 |
Phoenix REL-MR- 24DC/21 Single Relay – Technical Specifications
| Specification | Value |
|---|---|
| Product type | Single relay |
| Mechanical service life | 2x 107 cycles |
| Overvoltage category | III |
| Pollution degree | 3 |
| Maximum power dissipation for nominal condition | 0.17 W |
| Test voltage (Winding/contact) | 4 kV AC (50 Hz, 1 min., winding/contact) |
| Nominal input voltage UN | 24 V DC |
| Input voltage range | 14.4 V DC ... 66 V DC |
| Drive and function | monostable |
| Drive (polarity) | non-polarized |
| Typical input current at UN | 7 mA |
| Typical response time | 5 ms |
| Typical release time | 2.5 ms |
| Contact switching type | 1 changeover contact |
| Type of switch contact | Single contact |
| Contact material | AgSnO |
| Maximum switching voltage | 250 V AC/DC |
| Minimum switching voltage | 5 V (at 100 mA) |
| Limiting continuous current | 6 A |
| Maximum inrush current | 10 A (4 s) |
| Min. switching current | 10 mA (at 12 V) |
| Interrupting rating (ohmic load) max. | 140 W (at 24 V DC) |
| Connection method | Plug / solder connection |
| Width | 5 mm |
| Height | 28 mm |
| Depth | 15 mm |
| Degree of protection | RT III |
| Ambient temperature (operation) | -40 °C ... 85 °C |
| Ambient temperature (storage/transport) | -40 °C ... 85 °C |
| Standards/regulations | IEC 60664 |
| Mounting position | any |
| Coil resistance | 3390 Ω ±10 % (at 20 °C) |
| Switching capacity | 2 A (at 24 V, DC13) |
| Motor load according to UL 508 | 1/4 HP, 240 - 277 V AC (N/O contact) |
The Phoenix Contact REL-MR-24DC/21 (Part No: 2961105) is a compact Single Relay engineered for precise and energy-efficient control in industrial circuits. Operating at a nominal input of 24 V DC and supporting a wide range from 14.4 V to 66 V DC, the rel-mr-24dc/21 ensures flexibility across various control voltages. With a quick 2.5 ms response and a typical input current of 7 mA, this relay provides stable performance in automation logic and PLC systems.
The relay’s AgSnO contact material offers excellent electrical conductivity and wear resistance. Designed with a 6 A limiting current and maximum switching voltage of 250 V AC/DC, it supports resistive and inductive loads reliably. Its compact 5 mm width saves space inside control panels, while the plug/solder connection simplifies installation. Compliant with IEC 60664 standards and rated RT III for protection, the Phoenix Contact 2961105 relay ensures consistent operation between −40 °C and +85 °C, making it suitable for mission-critical automation applications.
The Phoenix Contact REL-MR-24DC/21 is preferred in process automation, HVAC systems, and PLC modules that require fast and reliable signal switching. Engineers choose this model for its compact design and quick response, which help maintain precise timing in motor control and safety circuits. The robust contacts minimize downtime and support smooth current transfer under high switching frequency. The Phoenix Relay 2961105 is also used in energy management systems and testing equipment where accuracy and longevity are critical. Its wide temperature tolerance and low power consumption make the Phoenix 2961105 a reliable choice for industrial and educational applications.




