ABB RXEDK 2H 1MRK000841-KA Binary Input/Output Module

The ABB RXEDK 2H 1MRK000841-KA is a high-performance binary I/O expansion module designed for ABB’s Relion® 615 series protection relays. As a critical interface component, this module extends the capability of feeder protection relays by adding 8 digital inputs and 5 configurable relay outputs to monitor status signals and execute control commands in medium-voltage switchgear. Engineered for substation automation, the ABB RXEDK 2H 1MRK000841-KA provides galvanic isolation between field devices and protection relays while maintaining the stringent response times required for grid protection schemes.

Part of ABB’s Relion product line, this module integrates directly with REF615 and RED615 relays via the rear-mounted connector system. Its core function is to bridge the gap between primary equipment (circuit breaker status, disconnector positions) and protection logic, enabling comprehensive feeder management without requiring additional control units. The ABB RXEDK 2H 1MRK000841-KA ensures reliable operation in electrically noisy environments through reinforced insulation and transient voltage suppression, making it essential for critical power distribution applications.

Detailed Parameter Table

Core Advantages and Technical Highlights

The ABB RXEDK 2H 1MRK000841-KA delivers robust performance for protection-critical applications:

Ultra-Fast Signal Processing: With ≤3 ms input response time, the module detects breaker status changes within half a power cycle. Output relays operate in ≤8 ms – crucial for arc flash mitigation sequences where total clearance must occur in <35 ms.

Reinforced Electrical Isolation: 4 kV RMS optical isolation between inputs/outputs and relay backplane prevents transient propagation during switchgear operations. Integrated varistors suppress surges up to 5 kV (1.2/50 μs), protecting relay processors.

Flexible Output Configuration: Each of the 5 outputs can be individually programmed as NO/NC contacts via PCM600 software. Contact rating (5A @ 250VAC) directly drives trip coils, alarms, or motorized disconnectors without interposing relays.

Wide Voltage Compatibility: Inputs accept 24-250 VDC or 48-230 VAC signals without external converters. Built-in filtering rejects contact bounce and EMI from VFDs or capacitor banks.

Environmental Resilience: Operates at -40°C without heaters – critical for unmanned substations. Conformal-coated PCB withstands 100% humidity and H₂S environments per IEC 60721-3-4.

Tool-Free Commissioning: Clip-on design enables module replacement in <2 minutes. LED per channel provides instant status indication (green=active, red=fault).

Typical Application Scenarios

The ABB RXEDK 2H 1MRK000841-KA excels in power distribution automation:

MV Switchgear Control: Monitors circuit breaker position (52a/52b) and drives trip/close coils in REF615-protected cubicles. Fast response prevents breaker restrike during fault clearance.

Transformer Protection: Interfaces Buchholz and pressure relief device contacts for RED615. Outputs trigger forced cooling or tap changer blocking during gas faults.

Solar Farm Combiners: Detects DC isolator status and commands sectionalizing switches during arc flash events. UV-resistant housing withstands direct sunlight.

Marine Power Management: Controls bus tie breakers in DNV-GL certified systems. Salt fog resistance prevents corrosion on offshore platforms.

Industrial Feeder Automation: Sequences motor starters via configurable outputs. Inputs verify starter auxiliary contacts before enabling next step.

Installation, Commissioning and Maintenance Instructions

Installation Preparation: De-energize the REF615 relay before inserting RXEDK 2H 1MRK000841-KA. Verify compatibility with relay firmware (≥3.0). Use copper conductors (0.5–2.5 mm²) with insulation ≥600V. Maintain ≥50 mm clearance from power cables.

Maintenance Suggestions: Annually, verify input threshold voltage with variable DC source. Exercise outputs under load (≥1A) to prevent contact oxidation. Monitor contact resistance via PCM600 diagnostics (>100 mΩ triggers alert). Replace if output contact erosion exceeds 50% of visible surface. During firmware upgrades, disconnect output loads to prevent spurious operation.

Service and Guarantee Commitment

ABB warrants the ABB RXEDK 2H 1MRK000841-KA for 60 months against defects. Comprehensive support includes:

24/7 access to ABB’s ProtectionCare® portal for configuration templates and firmware

On-site commissioning assistance with relay logic validation

Free replacement within 48 hours for critical grid applications

Lifetime calibration support with traceable certificates

Cybersecurity patches for IEC 61850 communication

Conformity to IEC 60255 standards with test reports

Spare parts guaranteed for 20 years post-discontinuation.