| 摘要 |
An automation technology, autarkic, field device, which is connected via two connecting terminals to an I/O module. The I/O module is embodied as a 4-20 mA/HART I/O module. The I/O module is associated with a controllable energy source via which the field device is supplied with energy. An electrical current measuring unit is provided which ascertains the electrical current supplied by the energy source. In the I/O module, internal resistors are provided, across which occurs in each case a voltage drop dependent on the flowing electrical current. A control unit is provided, which operates the energy source in such a way that a predetermined terminal voltage is supplied on the connecting terminals for powering the field device. |
