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NI CFP-AO-200

Product Introduction
cFP-AO-200 delivers eight isolated current output channels for Compact FieldPoint distributed I/O. It converts digital engineering setpoints from the controller into 0 to 20 mA or 4 to 20 mA field signals for valves, drives, indicators, and other current-loop actuators. The module is suitable for process automation, machine control, and remote I/O applications that require standardized analog output distribution.

Detailed content

Technical Specifications
The module provides eight analog current output channels. Output ranges are 0 to 20 mA and 4 to 20 mA with 0.5 mA overranging. Resolution is 12 bits. All-channel update rate is 200 Hz. With 24 V loop supply, each output drives up to 1 kΩ load; with 5 V loop supply, each output drives approximately 100Ω because of the internal 3 V drop. External loop power is 5 to 24 VDC. Single-channel response time is 3 to 6 ms; all eight channels update in 24 to 27 ms. Slew rate is 0.4 mA per microsecond. Isolation is 2300 Vrms transient overvoltage protection between the inter-module communication bus and I/O channels. Operating temperature is -40 to 70°C. Storage temperature is -55 to 100°C. Relative humidity is 10 to 90% noncondensing.
Function Features
Each channel includes open-loop detection with individual fault indication. Short-circuit protection is provided on output circuits. Hot plug-and-play recognition is supported on compatible powered backplanes. The module performs automatic scaling and linearization from engineering units to loop current. POWER and READY LEDs show module status; red indicators identify open current loops.
Application Scenarios
Control valve actuation, variable-speed drive setpoints, flow and pressure loop control, burner management interfaces, test equipment analog stimulation, and distributed current-output I/O for process and factory automation.
Performance Parameters
Twelve-bit DAC resolution provides 4096 output steps across the selected 0 to 20 mA or 4 to 20 mA range. The 200 Hz update rate supports closed-loop control with low output lag. Load drive depends directly on loop-supply voltage; higher supply voltage permits higher resistance without saturating the output stage.
Material Composition
The module uses an industrial printed-circuit assembly, isolated output drivers, conformal-coated components where specified, and a compact FieldPoint housing with plated screw or spring terminal interfaces.
Structure Features
cFP-AO-200 mounts on a Compact FieldPoint backplane cFP-BP-x. Captive screws and alignment keys secure the module. The connector or terminal interface provides I_OUT, COM, V_SUP, and loop-power terminals. Status LEDs are located on the front face for power, readiness, and per-channel open-loop indication.
Working Principle
The network module sends digital setpoints to cFP-AO-200. The module scales the engineering value, converts it through a 12-bit DAC, and drives a controlled current source into each field loop. Loop power is supplied externally to the V and C terminals. Monitoring circuits detect open circuits and excessive load; the module reports faults through LEDs and network diagnostics.
Installation Requirements
Install the module on a compatible Compact FieldPoint backplane inside a controlled or sealed cabinet. Align the module with backplane guides, seat it firmly, and tighten captive screws to 1.1 N·m with a No. 2 Phillips driver. Connect external 5 to 24 VDC loop supply to the voltage and common terminals according to load requirements. Use shielded cable and separate signal wiring from high-power circuits.

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