| 摘要 |
<p>Process for controlling the power of an electric through-flow heater in a three-phase system at a rated voltage of 21 kW and a minimum power of 3,5 kW, in which the controllable powers PR, 2PR, 4PR (where PR = 1 kW) are connected between two outer leads L1, L2, and in which further connectable power supplies are available in such a way that there is a symmetrical distribution. To avoid unacceptable mains reactions on the outer leads when these power supplies are switched on, the controllable power supplies are switched on simultaneously and in a mutually opposed manner.</p> |
