Product Core Brief

• Model: CI854, OEM Article Code 3BSE025347R1
• Brand: ABB Control Systems
• Series: CEX expansion bus communication module for AC800M / System 800xA DCS Controllers
• Core Function: PROFIBUS DP-V1 Class 2 master interface via CEX bus; paired exclusively with TP854 DIN rail termination base, dual DB9 ports support Profibus media redundancy, scans S800/S900 remote I/O, drives, smart transmitters, supports cyclic real-time exchange + acyclic HART device diagnostics and slave redundancyManualsLib.
• Product Type: Slide-in CEX bus Profibus master module, mandatory matching TP854 baseplate
• Key Specs: DP-V1 Class2 master | Dual DB9 redundant Profibus ports | Max 124 DP slaves | Official hot-swap certified | 500V galvanic isolationNote: Active OEM spare, new original surplus stock available; supports line redundancy and slave redundancy, up to 12 CI854 modules per single AC800M controller rackABB Group.

Key Technical Specifications

• Power supply: Powered by controller internal CEX backplane, power consumption max 5 W
• Profibus protocol: PROFIBUS DP-V0 cyclic I/O data + DP-V1 acyclic device parameter/diagnostic access (Class2 Master)
• Supported baud rates: 9.6 kbit/s ~ 12 Mbit/s full range configurable
• Physical interface: TP854 base carries two female DB9 RS485 connectors for redundant trunk wiring; each segment max 32 slaves, repeaters expand to total 124 slaves per channelManualsLib
• Cyclic data capacity: At 12 Mbit/s, total 4000 bytes combined input/output process data
• Minimum bus cycle time: 1 ms (single slave at 12 Mbit/s); typical 10–20 ms for multi-slave field stations
• Redundancy capability:
  1. Profibus media line redundancy (dual DB9 independent cable paths)
  2. Supports S800/S900 redundant I/O slave stations
• Galvanic isolation: 500 VAC dielectric separation between Profibus field side and CEX controller logic
• Core supported functions:
  1. HCIR: Add/remove Profibus slave devices online without full controller stop
  2. HART pass-through: Route DP-V1 HART secondary variables from AI815/AO815 I/O modules
  3. Full aggregated slave diagnostics: Wire-break, short-circuit, module supply fault, device offline alarms
  4. Automatic redundant bus switchover on primary cable failure
• PCB coating: ISA-S71.04 G3 grade conformal coating for mild corrosive power/chemical plant cabinet atmospheres
• Status indicators: Front multi-color LEDs: PWR, CEX RUN, BUS FAULT, CH1/CH2 Profibus communication status
• Mechanical form: Slide-in card locked to TP854 DIN rail base via alpha-code mechanical lock (prevents incompatible module insertion)ManualsLib
• Operating ambient: 0 °C ~ +55 °C continuous duty; compact vertical racks limited to 0 ~ +40 °C
• Storage range: -40 °C ~ +70 °C, non-condensing 5–95 % relative humidity
• Certifications: CE, UL508, ATEX II 3G Ex nA IIC T4 Gc Zone 2, cULus Class I Div 2 Groups A-D
• Dimensions (module + TP854 base): W59 mm × H185 mm × D127.5 mm; total weight 700 gABB

Product Introduction

is a high-performance PROFIBUS DP master expansion module for AC800M DCS, inserted into the controller rack’s CEX expansion bus to connect all Profibus DP field assets including S800/S900 distributed I/O, ABB ACS drives, HART smart valve positioners and third-party DP instrumentsABB Group.Dual independent DB9 ports on base realize full media redundancy, eliminating single cable failure risk for safety-critical control loops. Galvanic isolation suppresses ground-loop EMI noise from long field trunk cables and variable frequency drives, avoiding intermittent I/O value freezing or slave dropout.DP-V1 Class2 master function enables direct access to smart device diagnostic data without separate multiplexers; HCIR online modification avoids full process shutdown during field device expansion or replacement. Up to 12 modules can be installed in one AC800M rack to build large-scale multi-segment Profibus plant backbone architecturesABB Group.

QA & Testing SOP

1. Incoming Inspection: Cross-reference serial numbers and 3BSE part code against ABB AC800M spare databases. Inspect dual DB9 connector pin integrity, alpha lock matching, full LED bank functionality and intact factory anti-static packaging to filter counterfeit stock.
2. Live Testing: Install onto base inside AC800M test rack paired with PM865 CPU simulator. Run continuous 24-hour cyclic Profibus scan testing with mixed S800 I/O, drive and HART instrument slaves while logging stable CEX backplane supply via Fluke 115 multimeter. Simulate primary Profibus trunk disconnection, segment short-circuit and HCIR slave hot-add to validate automatic redundant bus failover and diagnostic flag timing.
3. Electrical Testing: Use 500V Megger to measure insulation resistance between Profibus field circuit and CEX bus logic; pass threshold ≥10 MΩ. Inject 50Hz differential ground-loop noise to confirm no random slave communication loss or bus switchover jitter.
4. Firmware/Config Backup: Record factory default Profibus baud rate, slave address mapping and redundancy parameters via Control Builder M engineering software. Capture high-resolution photos of dual DB9 pinout and wiring layout for field commissioning reference.
5. Final QC & Packaging: Fit plastic dust caps over both DB9 Profibus ports, bundle matched base accessory kit. Place module inside foam-lined anti-static shielding bag, affix a dated QC pass label before sealing in original factory carton.

Installation Pitfalls & Guide

❗Firmware Rev Mismatch Risk: controller firmware older than v5.1.0 lacks CEX register mapping for dual-line redundant bus failover and DP-V1 HART polling logic. Post-replacement, the DCS cannot switch to secondary cable on primary fault and throws intermittent PROFIBUS COMM LOSS alarms. Remediation: Flash matching firmware revision to PM86x CPU before inserting module onto base.❗Redundancy Cabling Misconfiguration Risk: Dual Profibus trunk lines must run separate physical cable trays to achieve true fault tolerance; routing both cables in one tray negates media redundancy during tray damage events.❗Profibus Termination Error Risk: Each Profibus segment only installs termination resistor on the farthest end slave device; duplicate or missing termination creates signal reflection, persistent scan jitter and random slave offline faults.❗Alpha Lock Mismatch Warning: base uses fixed A-D alpha mechanical lock; incompatible CEX modules cannot be physically inserted, avoid forced assembly damage.❗ESD Dangers: Ungrounded handling exposes dual Profibus transceiver and CEX bus logic traces to static discharge from dry control room air. Field records show unprotected handling burns both communication channels simultaneously; full process unit downtime labor cost exceeds $1,520. Remediation: Place anti-static mat under controller rack, wear grounded wrist strap, touch bare cabinet chassis ground for 3 seconds before handling module.

4-step replacement guide

1. Pre-install: supports official hot-swap; pause all Profibus cyclic polling logic blocks in Control Builder M first. Photograph dual DB9 trunk wiring layout, Profibus segment address mapping and redundancy mode configuration.
2. Removal: Unlatch base retention clip, slide upward out of base slot, disconnect dual DB9 Profibus trunk cables and store unit in static-safe sleeve.
3. Install: Insert new fully into base and lock retention latch; reconnect dual redundant Profibus trunk cables to matching DB9 ports, install end-of-line termination resistor on each segment’s farthest slave.
4. Power-on Test: Controller rack remains powered (hot-swap permitted); verify front CH1/CH2 COM LEDs illuminate steady green, perform full Profibus slave scan to confirm all field devices communicate correctly, test primary cable disconnection to validate automatic redundant failover before re-enabling automatic DCS closed-loop control.

FAQ

Q: Can be hot-swapped while the controller rack remains powered?A: Yes, carries official ABB IEC hot-swap certification for standard control room environments. No full rack power isolation required for replacement, only pause Profibus polling logic beforehand to avoid temporary field device data loss.

Q: Does this Profibus master module carry original OEM factory warranty when purchased as new surplus?A: ABB factory warranty follows standard component lifecycle coverage. All surplus inventory passes full in-house bench QA testing and carries a 12-month internal stock replacement warranty, limited to manufacturing defects detected during validation testing.

Q: Can CI801 serve as a direct functional replacement for ?A: No functional compatibility. CI801 is S800 rack local Profibus slave gateway, while is controller-side Profibus master CEX module; zero mechanical/software interchangeability, requires full bus architecture rework.

Q: What minimum CPU firmware version enables full dual-line redundancy and DP-V1 HART support?A: PM86x controller firmware v5.1.0 or newer. Older firmware omits redundant bus switchover register mapping and cannot retrieve HART secondary variable diagnostic data over DP-V1.

Q: Will Profibus slave address, baud rate and redundancy configuration persist after module replacement?A: All bus configuration data resides in CPU non-volatile memory; no local parameter storage on hardware. No full reconfiguration required post-swap, only complete Profibus slave scan and redundancy failover verification.

Q: Is compatible with legacy Advant AC450 / MasterPiece DCS racks?A: No. uses modern CEX expansion bus architecture, with zero electrical and mechanical compatibility with Advant AC450 CEX bus CI54x communication modules.

Q: How many Profibus slave devices can one master port connect?A: Single segment maximum 32 slaves; with Profibus repeaters cascaded, total up to 124 DP slave nodes per module dual-port trunk system.