1. APID auto-tuning adaptive control algorithm with no overshoot or undershoot, achieving ideal control performance; can also be set to ON-OFF mode for use as an alarm.

2. In addition to the traditional AT auto-tuning function, it also supports the advanced Yudian AAT rapid auto-tuning of PID parameters, which can significantly reduce equipment commissioning time in most cases.

3. Support multiple types of thermocouple and RTD input specifications.

4. Multiple alarm modes with customizable alarm output positions and 1-2 channels of alarm output.

5. Ultra-low power consumption, with instrument power usage around 0.2~0.3W when output is off.

6. Lightning-proof power protection, the instrument remains undamaged even under prolonged 380VAC misconnection.

7. In terms of output specifications, the AI-206/208 offers selectable outputs of either SSR (solid-state relay) or relay normally open contacts. The AI-226 supports a wider range of output options, including linear current/voltage, SCR zero-crossing/phase-shift triggering, and 1-4 channel alarm outputs.

8. In terms of measurement accuracy, the AI-206/208/226 models all have a 0.3 class accuracy.

9. In terms of communication, the AI-226 adds AIbus and Modbus communication capabilities.