Analog Input/Output Module Bachmann AIO208

Hardware Specifications

Industrial I/O Integration and Signal Scaling

The AIO208 combines multiple analog signal types within one I/O module. Consequently, the module can process voltage, current, RTD, and thermocouple inputs without requiring separate module types for each signal category.

The analog input section accepts voltage signals from +/- 10 V down to +/- 10 mV and current signals from 0(4) to 20 mA. It also supports Pt resistance temperature elements using 2-wire, 3-wire, or 4-wire connections. In addition, thermocouple inputs include types J, K, T, N, E, R, S, and B.

For output control, the module generates +/- 10 V voltage signals or 0(4) to 20 mA current signals. The 16-bit input resolution with filtering provides the stated input conversion resolution, while the output section uses 14-bit resolution.

The module provides 500 V galvanic isolation from the system. Therefore, field signal wiring remains electrically separated from the system-side interface within the specified isolation boundary.

Frequently Asked Questions

Q: What analog input signal ranges does the AIO208 support?
A: The module accepts analog voltage inputs from +/- 10 V to +/- 10 mV and analog current inputs of 0(4) to 20 mA.

Q: Which temperature sensors can the AIO208 interface directly?
A: The module supports Pt elements in 2-wire, 3-wire, and 4-wire configurations. It also accepts type J, K, T, N, E, R, S, and B thermocouples.

Q: What are the conversion resolutions and isolation characteristics?
A: The input section provides 16-bit resolution with filtering, while the output section provides 14-bit resolution. The system interface has 500 V galvanic isolation.

Field Installation Guidelines

• Install the module according to the applicable Bachmann system hardware and rack configuration requirements.
• Verify the selected field wiring matches the configured analog signal type before energizing the circuit.
• Use appropriate shielded instrumentation cable for low-level voltage, RTD, and thermocouple signals.
• Route analog signal cables separately from high-current switching and power conductors where practical.
• Terminate cable shields according to the plant grounding and EMC design requirements.
• For RTD inputs, maintain the selected 2-wire, 3-wire, or 4-wire wiring arrangement throughout the measurement circuit.
• Verify thermocouple wiring polarity and thermocouple type before commissioning.
• Confirm current-loop wiring polarity before applying power to 0(4) to 20 mA circuits.
• Check the specified 500 V galvanic isolation boundary when designing external field circuits.
• Do not infer operating temperature or power consumption from the supplied shipping dimensions or weight; consult the applicable Bachmann hardware documentation for those values.