The AO810V2 is a high-performance, high-reliability 8-channel analog output module designed for industrial automation and process control systems. This module supports standard 0~20 mA and 4~20 mA current output signals, making it suitable for various applications requiring analog control, such as valve positioning, speed control, pressure regulation, and temperature control. It features comprehensive diagnostic and protection functions, including output short-circuit protection, open-circuit detection, power supply monitoring, and fault-state preset output (OSP), ensuring safe and controllable operation even under abnormal conditions.
As an upgraded version of the AO810, the AO810V2 offers improvements in power supply adaptability, load capability, and diagnostic functions, making it suitable for a wider range of industrial environments. The module can be used with various Mounting Termination Units (MTUs), including TU810, TU812, TU814, and TU830, providing flexible system integration solutions.
II. Key Features
8 Independent Output Channels: Each channel configurable for 0~20 mA or 4~20 mA output.
High Precision & High Resolution: 14-bit resolution, with a maximum error not exceeding 0.1% (load 0~500 Ω).
Comprehensive Diagnostic Functions:
Module-level diagnostics: Output power supply undervoltage detection.
Channel-level diagnostics: Open-circuit detection (effective when output current > 1 mA).
Supports Output Set as Predetermined (OSP): Outputs can automatically switch to predefined safe values in case of communication failure or module error.
Robust Protection Mechanisms:
Wide Load Compatibility:
Supports Multiple Mounting Options: Compatible with Compact MTUs (TU810/TU814), D-Sub interface MTU (TU812), and Extended MTUs (TU830/TU833).
Group Isolated Design: Enhances system noise immunity and safety.
III. Functional Details
1. Output & Precision
The AO810V2 provides 8 fully independent analog current output channels. Each channel can be configured via software for 0~20 mA or 4~20 mA operation. The module utilizes a 14-bit high-precision Digital-to-Analog Converter (DAC), combined with auto-calibration and temperature compensation technology, ensuring output error does not exceed 0.1% over the entire temperature range. The output response is fast, with a rise time of only 0.35 ms, making it suitable for high-speed control loops.
2. Diagnostics & Monitoring
The module features a multi-level diagnostic mechanism:
Communication Monitoring: Verifies D/A converter communication status by reading back serial data.
Open-Circuit Detection: Triggers a channel fault alarm when the set output current is greater than 1 mA and the actual current is below the set value.
Power Supply Monitoring: Continuously monitors the output circuit supply voltage and reports a module-level error if undervoltage occurs.
Self-Diagnostics: The module performs periodic self-tests to ensure proper hardware and firmware operation.
3. Fail-Safe & OSP Function
When the module detects a severe error (e.g., communication loss, power supply anomaly), it can activate the "Output Set as Predetermined (OSP)" function. This forces all channel outputs to a user-predefined safe state (e.g., 0 mA, 4 mA, or hold last value), preventing equipment malfunction. The OSP time can be configured to 256 ms, 512 ms, or 1024 ms.
4. Electrical Protection & Compatibility
Outputs are short-circuit protected and can withstand temporary short circuits to ZP or +24 V.
Integrated EMC protection circuitry complies with industrial electromagnetic compatibility requirements.
Group isolated design effectively suppresses ground loop interference, enhancing system stability.
5. Power Supply & Load Compatibility
The module supports dual power input (L1+ and L2+). Users can choose the appropriate power connection based on load requirements:
When powered via L1+, the load resistance should be ≤ 500 Ω.
When powered via L2+, the load range can be extended to 250~850 Ω. Furthermore, the AO810V2 can drive an 850 Ω load even at the minimum operating voltage of 19.2 V, making it suitable for actuators at longer distances or with higher impedance.
IV. Installation & Wiring
The AO810V2 module must be used with a Mounting Termination Unit (MTU). It supports three main wiring methods:
1. Extended MTU (TU830/TU833)
Suitable for high-density, multi-channel systems. Provides screw terminals, supports dual power input and independent return lines (ZP) for each channel, offering clear wiring and easy maintenance.
2. Compact MTU (TU810/TU814)
Compact design ideal for space-constrained applications. Connects directly to field devices via screw terminals, eliminating the need for additional terminal blocks.
3. D-Sub Interface MTU (TU812)
Features a 25-pin D-Sub connector (male) for quick plug-and-play connections and standardized cabling, suitable for applications requiring frequent changes or testing.
All MTUs provide an EMC grounding terminal (EM) to ensure proper grounding of shielded cables and improve noise immunity.
V. Application Areas
The AO810V2 module is widely used in the following industrial scenarios:
Process Control: Flow, pressure, temperature, and level control in chemical, petroleum, and pharmaceutical industries.
Manufacturing Automation: Speed regulation, position control, and tension management in production lines.
Energy Management: Valve positioning control, excitation regulation in power plants and substations.
Building Automation: Frequency control for HVAC systems, pumps, fans, etc.
Testing & Measurement: Analog load driving, signal generation, calibration systems.
