| 摘要 |
<p>The primary interface (2) is linked to all the secondary interfaces (3) by a single, two-wire line (23) carrying an alternating supply current at low voltage, and control and monitoring information in the form of pulses; each secondary interface (3) is linked to all of its display fields (4) by a single two-wire line (34) carrying an alternating supply current at very low voltage, and control and monitoring information in the form of pulses; all the data are transmitted by using the principle of carrier currents. <IMAGE></p> |
