The ABB Ranza RK 881 023-BB (RXTUG 21H) is a high-reliability DC/DC converter module designed for the COMBIFLEX relay system. This model provides isolated and stabilized auxiliary power to protection relays and electronic circuits, ensuring consistent performance even during fluctuations in the primary station battery voltage.

 

Technical Specifications

Operational Precautions

• Terminal Mounting: Ensure the module is correctly seated in the RX 4 terminal base; uneven insertion can lead to arcing at the contact pins.
• Polarity Check: Verify input DC polarity before energizing; while protected, repeated reverse polarity can stress the internal filter components.
• Heat Dissipation: Maintain clear airflow around the COMBIFLEX rack to prevent thermal buildup during continuous high-load operation.
• Short Circuit Protection: The unit is self-protecting, but prolonged output shorts should be cleared immediately to prevent internal aging.

 

Common Q&A

Q: Can this unit handle varying station battery voltages? A: Yes, the RXTUG 21H is specifically designed to handle a very wide input range (24V to 250V DC) without requiring manual adjustments.

Q: Does it provide visual status indicators? A: The front panel typically includes a green LED to indicate that the output voltage is within the healthy stabilized range.

Q: Is it compatible with older “Ranza” series racks? A: It is fully compatible with the standard COMBIFLEX mounting system used across Ranza and other ABB protection families.

 

Recommended Similar Models

1. RXTUG 22H: A higher capacity variant for systems requiring more than 30W.
2. RXFE 4: A specialized filter unit often used in series with DC converters.
3. RXMSG 1: An auxiliary relay frequently powered by the RXTUG 21H output.
4. RK 881 007-AD: An alternative DC/DC module for specific voltage thresholds.
5. COMBIFLEX RX 4: The standard terminal base required for mounting this converter.