Control circuit for large hot water cylinder - has two temperature controllers controlling slow and fast heating circuits

摘要

The circuit has two temp. controllers and a switch, forming a slow heating circuit controlled by the first temperature controller, and a fast heating circuit controlled by the second temperature controller. The switch (SCH) in series with the controller (TR2) for fast heating circuit can shunt the above controller (TR2) and be connected to a self-holding circuit directly at the mains, in which the switch contact (d) is in series with the controller (TR1) for slow heating.