Description
Metso IOP371
Technical Specifications
- Card type: Analog mixed I/O card
- AI channels: 8 analog inputs
- AO channels: 4 analog outputs
- Input signals: 4 to 20 mA, 0 to 10 V, thermocouple, RTD
- Output signals: 4 to 20 mA
- Input accuracy: 0.1 % FS
- Output accuracy: 0.1 % FS
- Sampling period: 100 ms
- Supply: Rack backplane DC24V
- Isolation: Optical isolation between channel groups and backplane
- Temperature: 0 °C to +60 °C
- Storage: -20 °C to +70 °C
- Humidity: 5 % to 95 %, non-condensing
- Protection: IP20
- Installation: Eurocard plug-in
Functional Features
- 8-channel analog input supporting mA, voltage, thermocouple, and RTD
- 4-channel 4 to 20 mA output driving control valves and actuators
- Channel group optical isolation with single-group fault tolerance
- 0.1 % high-precision conversion
- Hardware wire-break and short-circuit diagnosis reported to CPU
- Front panel LEDs per channel status
- DNA bus isolated from field side
- Redundant channel configuration support
- Non-volatile card parameter storage
- Industrial-grade long-term reliability
Application Scenarios
- Chemical plant DCS process signal acquisition and valve output
- Paper machine process temperature, pressure, flow acquisition
- Metallurgical annealing furnace temperature loop control
- Pharmaceutical reactor process variable monitoring
- Metso DNA system process I/O cards
Materials and Construction
- Front panel: Flame-retardant engineering plastic
- PCB: FR4 multilayer board with conformal coating
- Analog devices: High-precision ADC and DAC chips
- Isolation: Optocouplers
- Passive components: Precision metal film resistors, ceramic capacitors
- Connector: Gold-plated Eurocard backplane connector
- Terminals: Screw-fastened tin-plated copper terminals
Structural Features
- Eurocard plug-in in Metso DCS rack I/O slots
- Front panel channel LEDs and field terminals
- Board partitions between AI, AO, and isolation areas
- Analog circuits placed away from digital bus interference
- Card locking mechanism resisting plant vibration
- Removable terminal block for easy maintenance
Working Principle Field 4 to 20 mA signals enter AI channels through terminals; after filtering and isolation, ADC samples digital values uploaded to the main CPU over the DNA bus. CPU control outputs are downloaded over the backplane to AO channels; DAC converts to 4 to 20 mA driving field control valves. Channel diagnostics monitor loop current to identify wire-break and short-circuit faults. LEDs indicate channel status.
Installation Requirements
- Insert card into rack I/O slot with power off
- Use shielded twisted pair for signal wires, single-point grounding
- Route signal and power cables separately
- Rack grounding
- Cabinet temperature 0 °C to +60 °C
- Configure channel type and range in DCS engineering software after power-up
Precautions
- Do not hot-swap during online operation
- Signal type configuration must match field sensors
- Wear ESD wrist strap
- Verify all channels from software after replacement
- Store spares in anti-static moisture-proof packaging
- Periodically calibrate analog accuracy
