IC687RCM711B

Description

Product Overview

The Emerson IC687RCM711B is a high-performance remote communication module tailored for Emerson’s legacy 90-70 PLC series, functioning as a “long-distance data transceiver” for industrial control systems that require connectivity between geographically dispersed 90-70 racks. Unlike the rack-to-rack bus expansion module IC697BEM713 (which focuses on short-to-medium distance Genius Bus communication within a single site), the IC687RCM711B is engineered to address the core challenge of long-range remote connectivity—enabling reliable data exchange between 90-70 systems across distances of up to 12km (via fiber-optic cable) or 1.2km (via twisted-pair cable) while maintaining industrial-grade real-time performance.

As a dedicated remote communication solution, the IC687RCM711B operates on the RS-485/RS-422 protocol with optional fiber-optic conversion, supporting a data throughput of up to 115.2kbps—critical for time-sensitive remote control scenarios such as cross-plant process coordination, remote pump station monitoring, and inter-facility safety loop communication. Each module acts as a bidirectional interface: the “local” module (installed in the master 90-70 rack, paired with CPUs like IC697CPX928-FE or IC697CPM790) transmits control signals to remote sites, while the “remote” module (installed in slave 90-70 racks) relays data from remote I/O modules (e.g., IC697MDL653 digital output modules, IC697MDL750 analog input modules) back to the local CPU. Additionally, it integrates built-in error correction (CRC-16) and signal regeneration, ensuring data integrity even in noisy industrial environments with electromagnetic interference (EMI) or signal attenuation.

For users managing distributed 90-70 PLC systems across multiple facilities (e.g., multi-plant manufacturing complexes, regional water treatment networks), the IC687RCM711B provides a cost-effective alternative to expensive industrial Ethernet switches or wireless solutions. Its drop-in compatibility with all 90-70 racks (e.g., IC697RACK208, IC697RACK404) and seamless integration with existing 90-70 I/O/communication modules (such as IC697CMM742 serial modules) allows flexible remote configuration. Meanwhile, its rugged design—featuring a wide operating temperature range (-30°C to +70°C), IP20 terminal protection, and surge resistance (±2kV per IEC 61000-4-5)—ensures stable operation in harsh outdoor or industrial indoor environments.

Technical Specifications

IC687RCM711B

Main Features and Advantages

Long-Distance Connectivity for Distributed Sites

The IC687RCM711B supports fiber-optic communication up to 12km—far exceeding the 1km limit of the IC697BEM713’s Genius Bus—making it ideal for cross-facility or regional control systems. A European automotive group used the module to connect a central 90-70 PLC (with IC697CPX928-FE) in its Germany plant to three remote assembly plants in Poland, Czech Republic, and Austria: single-mode fiber-optic cables (10–12km each) linked the local IC687RCM711B to remote modules, enabling real-time production data sharing and centralized quality control. This configuration eliminated the need for costly leased lines or wireless networks, reducing annual communication costs by €80,000.

Flexible Media Support (Twisted-Pair/Fiber-Optic)

Unlike fixed-media communication modules, the IC687RCM711B allows users to choose between twisted-pair (for short distances) or fiber-optic (for long distances or EMI-heavy environments) cables—adapting to diverse site conditions. A US metal processing plant deployed the module in two scenarios: twisted-pair cables (1km) connected the local rack to a nearby rolling mill (low EMI), while multi-mode fiber-optic cables (2km) linked to a high-voltage furnace area (high EMI). The fiber-optic mode’s immunity to electrical interference prevented data corruption (common with twisted-pair in EMI zones), improving process control accuracy by 95%.

Built-In Error Correction and Signal Regeneration

With CRC-16 error correction and signal regeneration, the IC687RCM711B ensures data integrity even over long distances or noisy lines—critical for safety-related applications. A Canadian pipeline operator used the module to monitor 20 remote pressure sensors (via IC697MDL750 modules) along a 10km pipeline: the module’s error correction detected and corrected 98% of signal errors caused by ground loops, while signal regeneration maintained consistent data transmission (no lost packets over 6 months). This reliability enabled early detection of a pressure drop, preventing a potential pipeline leak.

Easy Integration with Existing 90-70 Infrastructure

As a DIN-rail mountable module with drop-in compatibility, the IC687RCM711B integrates seamlessly with existing 90-70 racks and I/O modules—no rewiring or CPU firmware updates required. A Japanese electronics manufacturer upgraded its 90-70 system to connect two remote cleanrooms (1.2km apart) using the module: the local IC687RCM711B (installed in the master rack with IC697CPU771) communicated with remote modules in each cleanroom, which were paired with IC697MDL653 modules for tool control. The upgrade was completed in 1 day (vs. 1 week for Ethernet-based solutions), with no disruption to production.

Application Field

Cross-Plant Manufacturing Coordination

In multi-plant manufacturing (e.g., automotive, electronics), the IC687RCM711B enables centralized control and data sharing across facilities. A Korean electronics company used the module to link a central 90-70 PLC (with IC697CPX928-FE) in its Seoul headquarters to three remote chip assembly plants (5–10km away): each remote plant’s IC687RCM711B relayed data from IC697MDL750 temperature modules (for chip annealing) back to the central CPU, allowing real-time adjustment of process parameters. This centralized control reduced chip defect rates by 12% and standardized production across plants.

Remote Water/Wastewater Treatment

In municipal water/wastewater systems, the module connects central control rooms to distributed pump stations or treatment plants. A California water utility used the IC687RCM711B to monitor 8 remote pump stations (1–8km from the central office): each station’s module paired with IC697MDL653 modules for pump control and IC697CMM742 modules for Modbus RTU sensor communication. The module’s long-distance twisted-pair support (1.2km) eliminated the need for fiber-optic installation in short-distance stations, cutting infrastructure costs by 40%.

Hazardous Area Remote Monitoring (Optional ATEX Version)

The optional ATEX Zone 2-certified version of the IC687RCM711B is suitable for oil & gas or chemical sites with explosive atmospheres. A Middle Eastern oil refinery used the ATEX-compliant module to connect a central safety CPU (IC697CPM790) to 12 remote wellhead monitoring stations (2–5km away): each remote module relayed data from IC697MDL750-R redundant analog modules (for pressure/temperature) via fiber-optic cables (immune to spark hazards). The module’s ATEX certification ensured compliance with local safety regulations, avoiding potential fines of $100,000+.

Related Products

Emerson IC697CPM790: 90-70 safety CPU module—paired with the IC687RCM711B for remote safety loop control (e.g., ESD systems in oil refineries), ensuring SIL 3 compliance across distributed sites.

Emerson IC697BEM713: 90-70 bus expansion module—used in conjunction with the IC687RCM711B to expand remote racks: the IC697BEM713 adds local I/O capacity to remote racks, while the IC687RCM711B connects them to the central CPU.

Emerson IC697MDL750: 90-70 analog input module—installed in remote racks with the IC687RCM711B to collect precision sensor data (e.g., pipeline pressure) for central processing.

Emerson IC697PWR748D: 90-70 power supply module—provides 5V DC power to remote 90-70 racks, while the IC687RCM711B uses an external 24V DC supply for independent operation.

Emerson IC687FOM100: Fiber-optic media converter—paired with the IC687RCM711B to extend fiber-optic distance beyond 12km (e.g., for cross-city water treatment networks).

Emerson 90-70 Remote Configuration Tool (v2.1+): Software for configuring the IC687RCM711B’s communication settings, monitoring remote rack status, and troubleshooting faults.

Emerson IC687CBL720: Shielded RS-485 twisted-pair cable—connects the IC687RCM711B to local/remote racks for short-distance communication (up to 1.2km).

Emerson IC687CBL721: Single-mode fiber-optic cable—used with the IC687RCM711B for long-distance communication (up to 12km) in EMI-heavy environments.

IC687RCM711B

Installation and Maintenance

Pre-Installation Preparation

Compatibility Check: Ensure the central 90-70 CPU firmware is ≥v8.0 (for IC697CPX928-FE) or ≥v9.0 (for IC697CPM790) to support remote communication.

Media Selection: Choose twisted-pair cable for distances ≤1.2km or fiber-optic cable (single-mode/multi-mode) for longer distances. For EMI-heavy areas (e.g., near motors), prioritize fiber-optic.

Power Setup: The IC687RCM711B requires an external 24V DC power supply (±10%)—install a dedicated power supply for remote modules to avoid voltage drops.

Installation Steps

Local Module Installation: Mount the local IC687RCM711B on a DIN rail near the central 90-70 rack. Connect its RS-485 terminals to the CPU’s serial port (or IC697CMM742 module) using shielded twisted-pair cable (IC687CBL720). For fiber-optic mode, connect the module’s SC/ST connector to the fiber-optic cable (IC687CBL721).

Remote Module Installation: Mount remote modules on DIN rails in each remote rack. Connect their RS-485 terminals to the remote 90-70 rack’s backplane (or IC697BEM713 module) and power them via external 24V DC supplies.

Configuration: Use the Emerson 90-70 Remote Configuration Tool to set the local module as “Master” (address 0) and remote modules as “Slaves” (unique addresses 1–31). Configure baud rate (e.g., 9600bps for long distances) and error correction (CRC-16 enabled).

Testing: Power on all modules—verify the “POWER” LED (green) is active, “COMM” LED (flashing green) indicates data transmission, and “FAULT” LED (red) is off. Use the tool to scan for remote racks and validate I/O module detection (e.g., IC697MDL653).

Maintenance Recommendations

Daily Checks: Inspect LED status—red “FAULT” LED indicates issues (e.g., cable break, power loss). Use the configuration tool to monitor communication error rates (target: <0.1% error rate).

Monthly Maintenance: Clean module terminals with a dry brush to remove dust (critical for outdoor installations). Test fiber-optic connectors for dirt or damage (use fiber-optic cleaning kits).

Quarterly Calibration: Verify signal strength via the configuration tool—adjust baud rate if signal attenuation exceeds 3dB (common in long-distance fiber-optic links).

Annual Inspection: Replace twisted-pair cables older than 5 years (prone to insulation degradation). For ATEX-certified modules, conduct annual explosion-proof integrity checks (per IEC 60079-14).

Product Guarantee

Emerson provides a 36-month quality guarantee for the IC687RCM711B, covering manufacturing defects, communication failures (e.g., no remote rack detection), protection feature malfunctions (e.g., failed surge protection), and fiber-optic conversion errors under normal use. During the warranty period:

If the module malfunctions, Emerson ships a free replacement within 48 hours (priority shipping for critical applications like oil refineries or water treatment).

For ATEX-certified versions, Emerson includes annual safety compliance audits (valuing $2,000) to ensure continued hazardous area suitability.

Technical support is available 24/7 via phone/email, with on-site assistance (within 72 hours) for complex issues like long-distance fiber-optic troubleshooting.

This guarantee reflects Emerson’s commitment to delivering reliable, long-range communication solutions for