| 摘要 |
The method involves providing current to secondary power converter (13) to generate preset secondary power safety control signal. An electronic safety circuit (37) connected to converter is set based on electrical control signal (i) received by field device (1). An active state is adopted when control signal falls below or exceeds the current and voltage threshold values specific to safety circuit. The input current and voltage of control signal are modified so that test signal is generated and transmitted to safety circuit for testing functionality of field device. An independent claim is included for field device for sending control signal to final controlling device of industrial processing plant. |
