Overview

The Analog Input (AI) Module features three independent input channels. Each channel receives variable voltage signals from different points, converts them into digital values, and transmits these values to the three MPs on demand. A mid-value selection algorithm is employed to ensure accurate data for every scan. The design allows for sensing of each input point in a manner that prevents a single failure on one channel from affecting the operation of another channel.

Specifications

• Points: 32, commoned
• Nominal Input Current: 4–20 mA DC
• Operational Current Range: 2–22 mA DC
• Absolute Maximum Field Voltage: 33 V DC
• Absolute Maximum Reverse Field Voltage: –0.6 V DC
• Absolute Maximum Input Current: 50 mA DC
• Input Bandwidth (3dB): 16 Hz
• Source Impedance: 180 Ω
• Input Impedance (with baseplate): 250 Ω
• I to V Resistor: 100 Ω, ±0.01%
• Resolution: 12 bits
• Absolute Error: 0.15% of full scale (20 mA)
• Diagnostic: Force-to-value diagnostic (FVD)
• Scan Time: <1 ms for all 32 points
• Functional-to-Protective-Earth Isolation: 500 V DC, minimum
• Functional-to-Functional-Earth (Logic) Isolation: 800 V DC, minimum