UR4LH Digital I/O Module (Industrial-Grade Relay Interface)

The UR4LH is a high-performance digital input/output expansion module engineered for GE Multilin Universal Relay (UR) series platforms. Featuring 14 Form-A latchable relay outputs with no monitoring feedback, this module delivers reliable switching control for substation automation, power distribution protection, and industrial control applications requiring secure interlocking logic.

Designed to eliminate the complexity of external auxiliary relays, the UR4LH integrates seamlessly into UR chassis slots, enabling rapid deployment in mission-critical environments. Whether you're upgrading legacy protection schemes or building new SCADA-integrated substations, this module provides the output density and latching reliability demanded by utility-grade installations.

With ultra-fast 4ms activation time and wide operating temperature range (-40°C to 60°C), the UR4LH ensures consistent performance across harsh industrial environments while reducing panel space and wiring costs by up to 40% compared to discrete relay solutions.

Core Features & Benefits

✓ 14 Form-A Latchable Outputs
Provides mechanical latching relay contacts that maintain state during power loss, essential for fail-safe interlocking in circuit breaker control and transfer switch applications. Eliminates nuisance trips during momentary power interruptions.

✓ 4ms Ultra-Fast Activation
Delivers industry-leading response time for both wet and dry contact switching, enabling real-time fault isolation and load shedding in time-sensitive protection schemes. Reduces fault clearing time by 30-50% versus conventional electromechanical relays.

✓ Hot-Swappable Slot Design
Allows field replacement without system shutdown through UR series chassis integration. Minimizes maintenance downtime and supports live system upgrades in 24/7 operational facilities.

✓ High Power Contact Rating
Handles demanding switching loads for motor starters, solenoid valves, and annunciator circuits without external amplification. Reduces BOM costs and simplifies panel layout.

✓ No Monitoring Overhead
Optimized for applications where output state feedback is managed by external systems or not required, freeing up processing resources for protection algorithms and communication tasks.

→ Seamless UR Series Integration
Native compatibility with L90, D60, T60, F60, and all UR platform relays ensures plug-and-play deployment with existing Multilin ecosystems. Supports IEC 61850, DNP3, and Modbus protocols through host relay.

Typical Application Scenarios

Substation Automation & SCADA Control
Deploy in utility substations for remote breaker control, bus transfer switching, and capacitor bank automation. The latchable outputs maintain critical switching states during communication loss, while fast activation supports coordinated protection schemes across multiple feeders. Reduces substation commissioning time by 25% through simplified I/O wiring.

Industrial Power Distribution
Integrate into manufacturing facility power management systems for load shedding, generator synchronization, and emergency shutdown sequences. The module's high contact rating directly drives motor contactors and isolation switches without intermediate relays, cutting panel space requirements by 35%.

Renewable Energy Installations
Control inverter disconnect switches, battery management contactors, and grid interconnection relays in solar/wind farms. Latchable outputs ensure safe isolation states during maintenance, while wide temperature tolerance supports outdoor enclosure installations in extreme climates.

Data Center & Critical Infrastructure
Manage automatic transfer switches (ATS), UPS bypass controls, and generator start sequences in mission-critical facilities. The 4ms activation time enables seamless power source transitions with zero data loss, supporting Tier III/IV uptime requirements.

Marine & Offshore Platforms
Operate thruster controls, ballast pump interlocks, and emergency shutdown systems in harsh maritime environments. Conformal coating options and -40°C cold-start capability ensure reliable operation in offshore oil/gas and vessel power systems.

Technical Parameters & Selection Guide

Selection Criteria:

Choose the UR4LH when your application requires maximum output density without feedback monitoring. For applications needing contact status verification, consider the UR4LM variant with monitoring. If lower power switching is acceptable, the UR4LL model offers cost savings. Always verify contact ratings against your load requirements—inductive loads (motors, solenoids) may require derating or external suppression.

Extended Functions

SCADA/DCS Integration
When paired with UR series relays equipped with Ethernet or serial communication modules, the UR4LH outputs can be mapped to IEC 61850 GOOSE messages, DNP3 binary outputs, or Modbus coils for centralized control room operation. Supports both polled and unsolicited reporting modes.

Programmable Logic Sequences
Utilize the host UR relay's FlexLogic™ engine to create custom interlocking schemes, time-delayed transfers, and conditional switching logic without external PLCs. Reduces system complexity and improves reliability through single-platform integration.

Redundancy Configurations
Deploy multiple UR4LH modules across redundant UR relays for N+1 protection schemes. Latchable outputs ensure fail-safe states during relay switchover events, maintaining process safety in critical applications.

Customization Options
Factory configuration services available for pre-programmed output assignments, custom terminal labeling, and extended temperature/vibration ratings for specialized industrial or military applications. Contact our engineering team for project-specific requirements.

Delivery & Service Assurance

Lead Time
Standard stock items: 3-5 business days (subject to inventory availability)
Factory-configured units: 4-6 weeks
Express shipping available for emergency replacements

Warranty Coverage
24-month manufacturer warranty covering defects in materials and workmanship. Extended warranty plans available for critical infrastructure applications.

Technical Support
Access to certified GE Multilin application engineers for configuration assistance, troubleshooting, and system integration guidance. Remote commissioning support available via web conference.

Documentation Package
Each module ships with installation manual, wiring diagrams, FlexLogic programming examples, and IEC 61850 SCL files. CAD drawings and 3D STEP models available for download.

Frequently Asked Questions

Can the UR4LH interface directly with PLC digital inputs?
Yes, the Form-A dry contacts are compatible with standard PLC input modules rated for 24-48 VDC or 120-240 VAC. Ensure proper isolation and surge protection when interfacing with external control systems.

What is the maximum switching capacity per output?
High-power contacts typically handle 5-10A at 250VAC/30VDC (resistive load). Consult the official datasheet for derating curves with inductive or capacitive loads. For motor control applications, add RC snubbers or MOV suppressors.

How does the latchable feature improve energy efficiency?
Latchable relays consume zero holding power after activation, reducing module heat dissipation by 60-80% compared to continuous-coil designs. This extends relay life and lowers cooling requirements in enclosed panels.

What are the installation requirements for hot-swapping?
The UR chassis must remain powered, and the host relay firmware should be version 7.0x or later for automatic module recognition. Always follow lockout/tagout procedures even though electrical hot-swap is supported.

Is remote monitoring possible without onboard feedback?
While the UR4LH lacks integral contact monitoring, you can wire external auxiliary contacts or current sensors back to UR analog/digital inputs for closed-loop verification in safety-critical applications.

Can I mix UR4LH with other I/O modules in the same chassis?
Absolutely. The UR series supports heterogeneous module configurations—combine with UR4LM (monitored outputs), UR6DH (digital inputs), or UR8AH (analog inputs) based on your I/O requirements. Maximum module count depends on chassis model.

Get Your UR4LH Module Today

Ready to streamline your substation I/O architecture? Request a technical consultation to discuss your specific protection scheme requirements, or place your order now for fast delivery. Our team can provide application notes, wiring templates, and FlexLogic samples tailored to your project.

Contact our specialists: sale@ninermas.com | +0086 187 5021 5667

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