Hello! Im an indoor electrican apprenticeship student and I need help with solving a task we we're given, since I can't seem to figure it out.
A little context too: on the photo you can see a motor diagram, the thing is, when u press both the start buttons and all the contactors go down, you cant turn off 1 and 2 or 1 and 3 separately, you need to press both of the start buttons.
Our task was to find all the possible solutions to this problem and draw the new diagrams. Can anyone help me? Thanks in advance.

 

The diagram is not all that clear.
I assume you mean the "press both the STOP buttons" ?

We don't usually solve homework or test problems without some input from the poster.

 

The diagram is not all that clear.
I assume you mean the "press both the STOP buttons" ?

We don't usually solve homework or test problems without some input from the poster.

Yes, right now the only way to turn all of the contactors off without causing overload in thermal relay is to press both of the stop buttons simultaneously. The goal was to get it so start 1 turns on contactors 1 and 2 and then start 2 turns on contactors 3 and 2 and they can also work all at the same time. Stop 1 should turn off contactors 1 and 2 when all are working and stop 2 should turn off 2 and 3 when all are working. You have to use all components on diagram. I hope its clearer now.

 

Yes, right now the only way to turn all of the contactors off without causing overload in thermal relay is to press both of the stop buttons simultaneously. The goal was to get it so start 1 turns on contactors 1 and 2 and then start 2 turns on contactors 3 and 2 and they can also work all at the same time. Stop 1 should turn off contactors 1 and 2 when all are working and stop 2 should turn off 2 and 3 when all are working. You have to use all components on diagram. I hope its clearer now.

Here is a more understandable picture of the diagram.

 

Hi roll332,

Here's the control circuit that satisfies your conditions.



Nandu.