Switch monitor, at the electronic switch circuit for a multi-phase heating system, has an emergency direct input on a control defect

摘要

The technique is for monitoring the switches at an electronic circuit to open and close a multi-phase heating system (15,16) with the contact of a magnetically controlled switch (1) in each main current line (L1-L3,N) with a parallel contact of an auxiliary magnetically controlled switch (2) as a breaker and an electronic switch for each in series. Before each switch change, the contacts of the electronic switch (3) are closed and the switch is locked and the contacts of the auxiliary switch are opened. All the main current lines are measured at the input (4) and output (6) for a voltage drop to be registered at the micro-processor control (5). The current is measured (13) for a fault to be detected by the control. The impedance is registered at each heater. with open contacts, a weak current from the power supply (7) is used to test the relays (14) for short circuits. Temperature is measured by a sensor (19), the insulation is tested by a voltage connection (10) at the main current lines. An independent bridge control switches off the monitor relay (20) on a micro-processor defect, giving a direct link to an input (22) through a change contact (21) for the switch to be operated directly.