automation

1. CONTACTORS - AUTOMATION
1. Realization - so called “3-wires control”
Task:
To realize - the base connection for contactors automation; being used the ON and OFF push
buttons, as control elements. The power supply circuit can be seen in Fig. 1. The As. motor
protections are respected (it’s got enough in the diagram, only - as breaker). The control
circuit can be seen in Fig. 2.
Fig. 1. The power supply circuit diagram
Fig. 2. The control circuit diagram
2. Reversing Run – for 3-phase As. motor
- what is realised as the change of the phases sequence (to exchange 2 phases between
themselves). In Fig. 3 - the contactor KM1 is used for left side running; and KM2 – for right
side running. In control circuit - the breaking contacts KM1 and KM2 would be used as
blocking – to be prevented the short connection between power lines by the contemporary
switching of contactors KM1 and KM2.
Task:
To suggest and to verify the connection for control circuit – first by push buttons using;
second by limiting switches using - to be automatically shifted the collar (on the „moving
screw“ jig) from one side to the other one, and vice versa.
Fig. 3. The power supply circuit diagram - for bi-directional run