Description

ABB EI803F 3BDH000017R1

Basic Information

Physical Characteristics

Electrical Characteristics

Environmental Requirements

Communication Functions

Working Principle

I. Basic Positioning and Functions

II. Working Principle

1. Signal Input and Preprocessing
• Input Signal Types:
  Supports multiple analog signals, including:
• Current signals: 4-20mA (industrial standard, strong anti-interference).
• Voltage signals: 0-10V, ±10V, etc.
• Other signals: Temperature signals like RTD (Resistance Temperature Detector) and TC (Thermocouple) (some models require dedicated terminal modules).
• Preprocessing:
• Filters input signals (removes high-frequency noise) and conditions signals (e.g., amplifies or attenuates to ensure signals fall within the module's effective input range).
• Some modules support open-circuit detection (e.g., triggers an alarm when the current signal drops below 3.6mA).
2. Analog-to-Digital Conversion (A/D Conversion)
• Core Component: Built-in Analog-to-Digital Converter (ADC) to convert analog signals into digital signals.
• Conversion Principle:
  Periodically samples analog signals using the sampling theorem and quantizes samples into binary numbers (e.g., 12-bit, 16-bit, or higher resolution).
• Resolution Impact: Higher resolution (e.g., 16-bit corresponding to 65,536 quantization levels) ensures higher conversion accuracy and less signal detail loss.
• Conversion Speed: Depends on module design; high-speed modules support real-time applications (e.g., collecting rapidly changing process parameters).
3. Digital Signal Processing and Communication
• Digital Signal Processing:
  Converted digital quantities may require linearization (e.g., non-linear compensation for thermocouple temperature-voltage relationships), engineering unit conversion (e.g., converting current values to actual pressure values), and range limiting (setting upper and lower alarm thresholds).
• Communication Interface:
  Transmits processed digital signals to the controller CPU via the module's internal bus (e.g., FIELDBUS for ABB AC 800M systems).
• Communication Protocol: Follows the proprietary protocol of the control system (e.g., ABB's S800 I/O protocol) to ensure data real-time sex and reliability.
4. Power Supply and Module Self-Test
• Power Supply Mechanism:
  Uniformly powered by the control system's power module; some modules support redundant power input for enhanced reliability.
• Self-Test Function:
• Regularly performs hardware self-tests (e.g., ADC accuracy verification, memory status checks).
• When a fault is detected (e.g., power anomalies, channel damage), alarms via LED indicators and sends fault codes to the controller.

III. Typical Application Scenarios

• Process Automation: Monitoring temperature, pressure, and flow in chemical, pharmaceutical, and food & beverage industries.
• Power Systems: Collecting electrical parameters like voltage, current, and power in substations.
• Mechanical Equipment Monitoring: Acquiring analog signals (e.g., vibration, rotational speed) for fault diagnosis of large units.

IV. Key Technical Parameters

V. Collaboration with Other Modules

• Connection to Field Devices: Physically connects to sensors and transmitters via terminal modules (e.g., TB801), which provide signal terminals and electrical isolation.
• Interaction with Controllers: Transmits data to PLC/DCS controllers via backplane buses or communication modules (e.g., Communication Processor CM) to enable closed-loop control (e.g., adjusting valve openings based on collected temperature signals).

Common Fault Types and Possible Causes

I. Power-Related Faults

• Causes:
• External power failure (e.g., damaged power adapter, loose or disconnected wiring).
• Internal power circuit failure (e.g., blown fuse, aged capacitor, damaged chip).
• Symptoms: Module cannot start, all indicators are off, no communication or output signals.

• Causes:
• Input voltage exceeds the module's rated range (e.g., too high/low or fluctuating).
• Failed power filter capacitor, causing excessive ripple.
• Symptoms: Frequent module restarts, flashing indicators, or communication anomalies.

II. Communication-Related Faults

• Causes:
• Poor communication cable contact, breakage, or wiring errors (e.g., address conflicts, baud rate mismatches).
• Damaged module communication interface (e.g., burned RS-485/Ethernet interface chip).
• Firmware failure or program errors (e.g., incompatible firmware version, program crashes).
• Symptoms: Module shows "offline" or "unrecognized" in the system, or communication timeouts.

• Causes:
• Electromagnetic interference (e.g., nearby motors, inverters).
• Incorrect communication protocol configuration (e.g., parity bit, stop bit errors).
• Faulty internal communication buffer or degraded chip performance.
• Symptoms: Unstable data transmission, frequent parity errors, or data loss.

III. Input/Output (I/O) Faults

• No Response to Input Signals
• Faulty external signal source (e.g., damaged sensor, poor switch contact).
• Damaged input channel hardware (e.g., burned current-limiting resistor, failed optocoupler).
• Abnormal input circuit power (e.g., DC power failure, reverse polarity).
• Causes:
• Symptoms: Corresponding channel indicator is off; the system cannot read input signals.
• False Trigger/Misreport of Input Signals
• Signal interference (e.g., unshielded long cables, poor grounding).
• Input channel leakage or component aging (e.g., capacitor leakage causing unstable voltage levels).
• Causes:
• Symptoms: Module shows input active without external signals, or frequent signal state fluctuations.

• No Output Signal
• Output load overload or short circuit, triggering module protection (e.g., blown fuse, damaged output transistor/relay).
• Faulty output driver circuit (e.g., damaged driver chip, burned relay coil).
• Causes:
• Symptoms: No voltage/current output on the corresponding channel after system commands, load does not actuate.
• Abnormal Output Signal (e.g., Unstable Voltage/Current)
• Mismatched load characteristics (e.g., inductive load without freewheeling diode, causing back EMF damage).
• Aged output channel components (e.g., oxidized relay contacts, degraded transistor performance).
• Causes:
• Symptoms: Output voltage/current deviates from rated values, or unstable load actuation.

IV. Hardware Physical Faults

• Causes:
• Poor heat dissipation (e.g., inadequate ventilation, severe dust accumulation).
• Internal component short circuit (e.g., burned chip, capacitor breakdown).
• Symptoms: Significant elevated module surface temperature, possibly with unusual odors or smoke.

• Causes:
• Mechanical impact or vibration leading to loose interfaces or cracked circuit boards.
• Environmental factors (e.g., humidity, corrosive gases) causing terminal oxidation or circuit board corrosion.
• Symptoms: Cracked housing, detached terminals, or loose/broken circuit board solder joints.