Safety system for resistance heater in washing machine

摘要

The safety system for a clothes or dish washing machine, to prevent drying of the resistance heating, has two level switches (NV1, NV2) to monitor the normal water level, to control a switch (R) in series. The switch (R) controls the control motor (StM) and switches off the water feed valve (WV). After a given running time in the heating and washing cycle, after the water feed phase, the control motor (StM) switches (R) the heating resistance (R) in parallel through control contacts (tm1, tm2).