Before procurement teams confirm REL-MR-12DC-21AU-MS, they typically review SMPS Phoenix, Phoenixcontact Rel Ir Bl L 230Ac 4X21 and Phoenix Contact Relay Socket to double-check performance ratings, stock availability, and supplier credibility carefully.
Phoenix REL-MR- 12DC/21AU/MS Single Relay
The Phoenix REL-MR- 12DC/21AU/MS Single Relay (Part No: 2909644 ) offers a 12 V DCnominal input voltage UN, 7.2 V DC ... 33 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- 12DC/21AU/MS |
Phoenix REL-MR- 12DC/21AU/MS Single Relay β Technical Specifications
| Specification | Value |
|---|---|
| Product type | Single relay |
| Mechanical service life | 1x 107 cycles |
| Insulation | - |
| Overvoltage category | III |
| Pollution degree | 3 |
| Service life electrical | - |
| Maximum power dissipation for nominal condition | 0.17 W |
| Test voltage (Winding/contact) | 4 kV AC (50 Hz, 1 min., winding/contact) |
| Test voltage (Changeover contact/changeover contact) | - |
| Rated insulation voltage | - |
| Rated surge voltage | - |
| Nominal input voltage UN | 12 V DC |
| Input voltage range | 7.2 V DC ... 33 V DC |
| Drive and function | monostable |
| Drive (polarity) | non-polarized |
| Typical input current at UN | 14 mA |
| Typical response time | 2.5 ms |
| Coil voltage | - |
| Status display | - |
| 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 | 50 mA |
| 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 | 16 mm |
| Degree of protection | RT II |
| Degree of protection (Installation location) | - |
| Ambient temperature (operation) | -40 Β°C ... 85 Β°C |
| Ambient temperature (storage/transport) | -40 Β°C ... 85 Β°C |
| Standards/regulations | IEC 60664 |
| Mounting type | - |
| Mounting position | any |
| Mains frequency | - |
| Typical release time range | - |
| Coil resistance | 848 Ξ© Β±10 % (at 20 Β°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) |
| Input power dissipation for UN | - |
| 3-phase motor load | - |
| Product family | - |
| Relay type | - |
| Test voltage () | - |
| Degree of protection (Relay) | - |
| Inrush current, minimum | - |
| Non-operate voltage | - |
| Safe operate voltage | - |
| Test voltage (N/O contact / N/O contact) | - |
Phoenix Contact REL-MR-12DC/21AU/MS (Part Number: 2909644) is a compact and durable 12V Input Voltage Single Relay designed to operate reliably in automation systems. This electromechanical relay offers a nominal coil voltage of 12 V DC with a wide input tolerance range from 7.2 V DC to 33 V DC, making it highly adaptable in industrial environments. It features AgSnO contact material for extended lifecycle and can switch voltages up to 250 V AC/DC while handling a continuous current of 6 A. With a mechanical service life of 10 million cycles and a rapid response time of 2.5 ms, it provides the stability and performance expected in high-speed automation logic.
This model is built with a compact 5 mm housing and RT II protection rating, suitable for space-constrained PLC interfaces and control cabinets. Its Plug / Solder connection method ensures quick installation and dependable signal transmission. Compliant with IEC 60664 standards and rated for use in overvoltage category III and pollution degree 3 conditions, the REL-MR-12DC/21AU/MS relay meets the needs of both OEM panel builders and maintenance engineers. For other high-performance relay solutions, visit our Phoenix Relay category or explore more from the Phoenix Contact brand.
Whether youβre designing new automation panels or replacing legacy signal relays, the REL-MR-12DC/21AU/MS is engineered for long-term dependability. With Phoenix Contactβs global reputation and compliance to industrial standards, this relay is a top choice for OEMs and control panel integrators seeking durability, precision, and compact design.







