The AI890 Analog Input Module has 8 channels. The module includes Intrinsic Safety protection components on each channel for connection to process equipment in hazardous areas without the need for additional external devices.
Each channel can be either a current input or power and monitor a two-wire process transmitter. The current input is for externally powered transmitters. The input voltage drop of the current input is typically 3 V, PTC included. The transmitter supply for each channel can provide at least 15 V at a 20 mA loop current to power Ex-certified process transmitters and is limited to 23 mA in overload conditions. All eight channels are isolated from the ModuleBus and power supply in one group. Power to the input stages is converted from the 24 V on the power supply connections.
TU890 and TU891 Compact MTU can be used with this module and it enables two wire connections to the process devices without additional terminals. TU890 for Ex applications and TU 891 for non-Ex applications.
Features and benefits
• 8 channels for 0...20 mA or 4...20 mA, single ended unipolar inputs.
• 1 group of 8 channels isolated from ground.
• Power and monitor for Ex certified two-wire transmitters.
• Non energy-storing analog inputs for externally powered sources.