Phoenix Contact REL-MR-BL-24DC/21HC Single Relay – 24 V DC Coil, 1 Change-over Contact (SPDT), High-Continuous-Current Plug-in Miniature Power Relay

Detailed Description:

The Phoenix Contact REL-MR-BL-24DC/21HC (Item No. 2906285) is a high-performance plug-in miniature power relay engineered for demanding industrial automation and control applications requiring robust switching with high continuous current capability. It features a 24 V DC nominal coil voltage and a single change-over (SPDT) contact configuration housed in a compact module format. 

Key Features & Benefits:

• 24 V DC coil, non-polarised drive, input voltage range approx. 16.8 V-54 V DC, typical input current ~17 mA. 

• 1 change-over contact (single contact): allows switching between a common underlying circuit to NO/NC contacts, offering flexible control configurations. 

• High continuous current capability: Limiting continuous current up to ~16 A; maximum inrush up to ~30 A for 300 ms in this model variant. 

• Switching voltage rating up to 250 V AC/DC; minimum switching voltage down to 5 V at small currents. 

• Compact, space-efficient design: width approx. 12.7 mm, height 29 mm, depth 15.7 mm — ideal for dense panel mounting or modular socket systems. 

• Built for industrial environments: Ambient operating temperature –40 °C to +85 °C; insulation rated basic, overvoltage category III, pollution degree 3. 

• Plug-in mounting style simplifies installation, relay replacement and serviceability. 

Typical Applications:
This relay is suitable when a compact but high-reliability switching element is required, for example:

• Interface between PLC output modules and higher-power loads in control cabinets.

• Switching motors, solenoids or loads in automation systems with 24 V DC logic/control.

• High density automation rack systems or modular machine control frames requiring minimal footprint relays.

Scope of Delivery:
One (1) Phoenix Contact REL-MR-BL-24DC/21HC relay (Item No. 2906285) as described.

Installation & Use Notes:

• Confirm your coil supply is 24 V DC nominal and falls within the stated input voltage range (≈ 16.8–54 V DC) for reliable actuation. TME

• Ensure the load switched by the contact does not exceed ~16 A continuous (or the appropriate inrush limits) and that the voltage ratings match or exceed your application.

• Use a compatible relay socket or mounting base that supports plug-in mini-relays for ease of maintenance.

• Allow for ambient temperature and environment ratings as specified (–40 °C to +85 °C) when selecting for panel mounting.

Manufacturer / Item Number: Phoenix Contact, Item No. 2906285.

Summary:
The REL-MR-BL-24DC/21HC offers a premium-quality miniature power relay solution with a 24 V DC coil, single change-over contact, and high continuous current capability — making it an excellent choice for automation and control systems demanding both compactness and performance.