The AIM2 is an interface device designed to optically isolate an analog input signal (voltage or current) from its corresponding output signal. This isolation helps prevent ground loops and electrical noise from affecting the signal integrity. The device is versatile, accepting a wide range of input signals and producing a variety of output signals within those ranges.

Function Description:

The primary function of the AIM2 is signal isolation and conversion. It takes an analog input, which can be either a voltage (0-20 VDC) or a current (0-20 mA), and produces an isolated analog output within the same ranges. Both input and output signals can be configured as either voltage or current, and current signals can be set as either sink or source. This flexibility makes the AIM2 suitable for various industrial and building automation applications where signal integrity and isolation are crucial.

The device incorporates an onboard 24 VAC isolation transformer to supply power to the isolated output, ensuring true isolation between the input and output stages. An external 24 VAC isolation transformer with a floating secondary is required to power the AIM2 itself.

The AIM2 is field-calibratable, allowing users to fine-tune its performance to specific application requirements. Factory calibration is also available as an option for those who prefer a pre-configured device, which can expedite installation.

Important Technical Specifications:

Supply Voltage: 24 VAC (+/- 10%), 50/60 Hz
Supply Current: 200 mA maximum
Input Voltage Signal Preset Ranges: 0-5V, 0-10V, 0-15V, 0-20V, 1-5V, 2-10V, 3-15V, 4-20V, 0-1V
Input Current Signal Preset Ranges: 0-20 mA, 4-20 mA, 0-1 mA
Input Signal Adjustable Voltage Span: 1 VDC (Minimum) to 20 VDC (Maximum)
Input Signal Adjustable Voltage Offset: From 0 to 20 VDC
Input Signal Adjustable Current Span: 4 mA (Minimum) to 20 mA (Maximum)
Current Offset: From 0 to 20 mA
Input Voltage Impedance: 9,500Ω
Input Current Impedance: 250Ω +/-1%
Output Voltage Signal Preset Ranges: 0-5 VDC, 1-5 VDC, 0-10 VDC, 2-10 VDC
Output Current Signal Preset Ranges: 0-20 mA, 4-20 mA
Output Signal Adjustable Voltage Span: 1 VDC (Minimum) to 20 VDC +/- 1 VDC (Maximum)
Output Signal Adjustable Voltage Offset: From 0 to 10 VDC
Output Signal Adjustable Current Span: 0 mA (Minimum) to 20 mA (Maximum)
Output Signal Adjustable Current Offset: From 0 to 20 mA
Output Voltage Impedance: 5,000Ω
Output Current Impedance: 500Ω
Accuracy: +/- 3%
Linearity: +/- 1%
Connections: 45° Captive screw Terminal Blocks
Wire Size: 12 (3.31 mm²) to 22 AWG (0.33 mm²)
Terminal Block Torque Rating: 0.5 Nm (Minimum); 0.6 Nm (Maximum)
Operating Temperature Range: 35 to 120°F (1.7 to 48.9°C)
Operating Humidity Range: 10 to 95% non-condensing
Storage Temperature: -20 to 150°F (-28.9 to 65.5°C)
Dimensions: 4.60" (116.84mm) L x 3.23" (81.90mm) W x 0.70" (17.78mm) H (excluding snap track)

Usage Features:

Flexible Input/Output Configuration: The AIM2 supports a wide array of voltage and current input/output ranges, both preset and adjustable. This allows it to adapt to diverse control systems and sensor types. DIP switches and jumpers are used to configure these settings.
Voltage and Current Signals: The device handles both voltage (VDC) and current (mA) signals for both input and output.
Sink/Source Capability: For current signals, the AIM2 can be configured for either sink or source operation, providing compatibility with different current loop configurations.
Optical Isolation: The core feature of the AIM2 is its optical isolation, which breaks the galvanic connection between the input and output, preventing ground loops and protecting sensitive equipment from electrical disturbances.
Field Calibratable: Users can calibrate the input and output signals in the field to achieve precise measurements and control. This involves adjusting MIN and MAX pots and using a voltmeter to verify signal levels at designated test points (TP1 and TP3).
Snap Track Mounting: The device is designed for easy mounting in a snap track. It can be mounted in any position. Users are advised to use only fingers to remove the board from the snap track and avoid flexing the board or using tools to prevent damage.
DIP Switch and Jumper Settings: Configuration of input and output ranges, as well as direct or reverse acting output, is done via DIP switches and jumper blocks (J2, J3, J4, J5). Detailed tables are provided in the manual to guide users through these settings.
Shielded Cable Grounding: When using shielded cables, it is crucial to ground the shield only at the controller end to prevent ground loops.
Dedicated Isolated Transformer: The AIM2 requires its own dedicated isolated UL-listed class 2 transformer for power. It should not be connected to or share a transformer with any other device to maintain proper isolation and performance.
Compliance: All wiring must comply with local and National Electric Codes.

Maintenance Features:

Static Discharge Precautions: Before handling the device, users are instructed to ground themselves to discharge static electricity, as some components are static sensitive.
Power Disconnection during Wiring: It is critical to remove power before connecting or disconnecting any wiring to prevent damage to the device or injury.
Calibration Procedures: The manual provides detailed step-by-step instructions for calibrating both input and output signals, including procedures for preset and adjustable ranges, and for setting offsets and spans. This allows for ongoing accuracy and performance optimization.
Troubleshooting (Implicit): While not explicitly stated as "troubleshooting," the calibration steps and wiring precautions serve as a guide to ensure correct setup and operation, which inherently helps in preventing and resolving common issues.
Warranty: The AIM2 Series is covered by ACI's Two (2) Year Limited Warranty, details of which can be found in ACI's SENSORS & TRANSMITTERS CATALOG or on their website.

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