Emerson A6824 | Modbus TCP/RTU Interface Module for AMS 6500

• Description

Hard-Numbers: Technical Specifications

• Protocol Support: Modbus TCP/IP (10BaseT), Modbus RTU (RS-485)
• Port Count: 1×RJ45 (Ethernet), 1×RS-485 (serial)
• Baud Rate: RTU fixed 19.2 kbaud; 8N1, even parity
• Operating Temperature: 0°C to +65°C (storage -30°C to +85°C)
• Isolation Rating: 1500V RMS channel-to-backplane
• Power Draw: 24VDC, max 5W (208mA)
• Data Types: Vibration, speed, gap, temperature, alarm/status
• Response Time: <100ms real-time updates
• Dimensions: 30mm (6TE) × 128.4mm × 160mm
• Compliance: API 670, IEC 68-2-6/29 (vibration/shock)

The Real-World Problem It Solves

AMS 6500 vibration/protection data trapped in the rack; no standard link to DCS forces hardwiring or custom gateways. No local display capability means techs carry laptops everywhere.Where you’ll typically find it:

• Power plant turbine/generator AMS 6500 racks linking to Ovation/DeltaV
• Refinery compressor trains needing Modbus RTU to SCADA
• Any API 670 system requiring both remote monitoring and local HMIThis module eliminates custom wiring, enables redundant comms, and powers local displays for at-a-glance machine health.

Hardware Architecture & Under-the-Hood Logic

A6824 is the rack’s central data concentrator; no onboard sensor processing, just high-speed backplane polling and protocol conversion. Hot-swappable, independent of protection logic.

1. High-speed backplane interface polls all A6500 modules (A6110/A6210/A6410) for data.
2. Onboard 32-bit MCU buffers and scales values (vibration, speed, alarms).
3. Dual protocol stacks run in parallel: TCP/IP (Ethernet) and RTU (RS-485).
4. Redundant paths configurable; auto-failover if one link drops.
5. Front-panel SMB/serial port drives local graphical HMI for rack-side viewing.
6. Isolation blocks ground loops; 1500V RMS protects backplane from plant noise.

Emerson A6824

Field Service Pitfalls: What Rookies Get Wrong

IP address conflicts & subnet mismatchesNew techs deploy multiple A6824s with default 192.168.255.1; no subnet planning causes network storms and lost data.

• Field Rule: Set unique static IPs; match plant subnet; disable unused ports.

RTU wiring polarity & termination errorsReversing RS-485 +/- or missing 120Ω termination causes intermittent data drops and CRC errors.

• Quick Fix: Verify A/B polarity; add 120Ω resistor at bus end; ground shield at rack only.

Overloading the backplane with too many modulesPacking the rack with >12 high-data modules (e.g., 8×A6110) without bandwidth planning slows updates >500ms.

• Field Rule: Limit to 10 modules max; stagger update rates; use TCP for high-priority data.

Commercial Availability & Pricing Note

Please note: The listed price is for reference only and is not binding. Final pricing and terms are subject to negotiation based on current market conditions and availability.