ABB D674A906U01

Description

Detailed Parameter Table

ABB D674A906U01

Product Introduction

The D674A906U01 is a compact auxiliary relay module from ABB, designed to facilitate signal switching and interlocking in industrial control and power distribution systems. As a critical component in automation and protection circuits, it converts low-power control signals (110 V DC) into high-power outputs, enabling the operation of larger devices such as contactors, indicators, or alarm systems.

Engineered for reliability, this relay module features 4 changeover contacts (normally open/normally closed) that provide flexible wiring options for diverse control logic. Its rugged polyamide housing and wide operating temperature range (-25°C to +70°C) ensure consistent performance in harsh industrial environments, including power substations, manufacturing plants, and utility networks. Whether integrated with ABB’s REF615 feeder protection relays or third-party control systems, the D674A906U01 delivers precise signal transmission, enhancing the safety and efficiency of electrical systems.

Core Advantages and Technical Highlights

Fast switching performance
With a pickup time of ≤10 ms and drop-out time of ≤5 ms, the D674A906U01 ensures rapid response to control signals. In a power substation’s feeder protection scheme, this speed is critical for activating trip circuits or alarms within milliseconds of a fault detection by the REF615 relay, minimizing damage to equipment.

Flexible contact configuration
The 4 changeover contacts (NO/NC) allow versatile integration into complex control logic. In an industrial conveyor system, for example, the relay can:

Use a normally open contact to start a motor via a contactor

Use a normally closed contact to interlock with an emergency stop circuit

Provide auxiliary signals to a SCADA system via additional contacts
This eliminates the need for multiple relays, simplifying wiring and reducing cabinet space.

Industrial-grade durability
The relay’s polyamide housing (UL94 V0) resists flame propagation, while its 2 kV dielectric strength protects against electrical interference. In a chemical plant’s control panel, where vibration and airborne contaminants are common, the D674A906U01 maintains contact integrity, ensuring reliable operation of safety interlocks for years.

Typical Application Scenarios

In a medium-voltage power distribution substation:

D674A906U01 modules are used as auxiliary relays in the RET670 transformer protection system, converting low-voltage trip signals from the relay into high-power outputs to operate circuit breaker coils.

Their changeover contacts provide status feedback to the substation SCADA system, indicating whether the breaker is open or closed.

The 110 V DC coil voltage matches the substation’s control battery system, ensuring compatibility with existing infrastructure.

In a manufacturing plant’s motor control center (MCC):

The relay module interfaces between PLC outputs and motor contactors, isolating low-voltage control signals from high-power motor circuits.

Normally closed contacts are used to interlock multiple motors, preventing simultaneous startup of conflicting equipment (e.g., conveyor and gate motors).

DIN rail mounting allows easy integration alongside other control components, simplifying panel assembly and maintenance.

ABB D674A906U01

Related Model Recommendations

D674A907U01: 220 V DC variant of D674A906U01 for systems with higher control voltage.

REF615: ABB feeder protection relay compatible with D674A906U01 for substation applications.

RET670: Transformer protection relay that uses D674A906U01 for auxiliary signaling.

CR-MX2: ABB miniature circuit breaker to protect D674A906U01 coil circuits.

1SNA683001R1210: ABB terminal block for wiring D674A906U01 contacts and coils.

D674A905U01: 24 V DC version for low-voltage automation systems.

Installation, Commissioning and Maintenance Instructions

Installation preparation
Mount D674A906U01 on a 35 mm DIN rail, ensuring a minimum clearance of 5 mm from adjacent components for cooling. Connect the 110 V DC coil (terminals A1/A2) to the control circuit, using 0.5-1.5 mm² wire. Wire the changeover contacts (terminals 11-12/21-22/31-32/41-42) to the load devices (contactors, indicators, etc.), ensuring the load current does not exceed 10 A @ 250 V AC. Secure all connections with torque of 0.5-0.7 Nm to prevent loose wiring.

Commissioning steps
Apply 110 V DC to the coil and verify the relay actuates (audible click). Check that normally open contacts close and normally closed contacts open using a multimeter. Test contact continuity under load to confirm they can handle the rated current without voltage drop exceeding 500 mV. Cycle the relay 10 times to ensure mechanical reliability, then integrate with the control system (e.g., PLC or protection relay) to verify signal transmission.

Maintenance suggestions
Inspect D674A906U01 quarterly for loose connections or signs of overheating (discolored terminals). Clean contacts annually using a soft brush to remove dust or oxidation—avoid abrasive materials that could damage contact surfaces. Measure coil resistance yearly (should be within ±10% of nominal value) to detect degradation. Replace the relay if contacts show excessive pitting, if coil resistance is out of range, or if switching times exceed specifications. Use only ABB-approved replacements to maintain system compatibility.

Service and Guarantee Commitment

The D674A906U01 is backed by a 2-year warranty, covering defects in materials and workmanship under normal operating conditions. ABB’s technical support team provides guidance on wiring diagrams, compatibility with protection relays (e.g., REF615), and troubleshooting control logic issues.

Customers receive access to detailed datasheets and application notes for D674A906U01, including contact rating charts and mounting guidelines. ABB ensures global availability of replacement modules, minimizing downtime for critical control and protection systems. With expertise in industrial relays, ABB’s support network helps users optimize the relay’s performance in power distribution and automation applications.