| 摘要 |
The self-monitoring switch circuit comprises: a first sub-circuit (14), which is connected to a first relay (16) having a first switch-over contact (18) that includes a first normally closed contact and a first normally open contact; a second sub-circuit (15), which is connected to a second relay (17) having a second switch-over contact that includes a second normally closed contact and a second normally open contact, where one of the two sub-circuits comprises a sensor input, and each of the first normally open contact is connected with the second normally closed contact. The self-monitoring switch circuit comprises: a first sub-circuit (14), which is connected to a first relay (16) having a first switch-over contact (18) that includes a first normally closed contact and a first normally open contact; a second sub-circuit (15), which is connected to a second relay (17) having a second switch-over contact that includes a second normally closed contact and a second normally open contact, where one of the two sub-circuits comprises a sensor input, each of the first normally open contact is connected with the second normally closed contact, and the first normally closed contact is connected with the second normally open contact; and a detection circuit at which a signal circuit is connected, where the signal circuit contains series circuit formed form the open and closed contacts, and produces an error signal in determination of a power interruption into the signal circuit. The first and second relays are held in a waiting state of the switch circuit in different states. The sensor input: is an input of a capacitance measuring device; and is connected with a condensator, which is connected with a controllable switch in series. The switch has a control input connected with the sub-circuits. One of the two sub-circuits is arranged to start a checking routine. The switch is closed within the checking routine to shift the first relay connected with a relevant sub-circuit, where the second relay is simultaneously shifted. A fixed time interval is provided for triggering the checking routine. An other sub-circuit is equipped to switch its associated relay when the sub-circuit receives no input signal for a predetermined time period, which is greater than the time interval for triggering the checking routine. An independent claim is included for a method for monitoring a function of a switch. |
