How to reverse 3AC motor having 4-pole contactors. 
<ul><li>Let's see: hot wire incomes to normally closed (NC) button S3, then it devides to red and orange circuits. Orange circuit drives K1 contactor and red circuit drives K2 contactor. Orange wire comes through NO contacts in S2 and NC contacts in S1. There are blocking contacts (7-8) in parallel to NO contacts on both contactors.
<ul><li>So, we push S2 button - NO contact turns orange circuit on and NC contact is protecting against casual short circuit; the current start to pass through hot wire -&gt; S3 -&gt; NO in S2/7-8 in contactor K1 -&gt; NC in S1 -&gt; contactor's K1 coil -&gt; neutral.</li>
<li>We push S1 button - NC interrupts working orange circuit (to protect against casual short circuit) and NO turns red circuit on; so the current start to pass through hot wire -&gt; S3 -&gt; NC in S2 -&gt; NO in S1/7-8 in contactor K2 -&gt; contactor's K2 coil -&gt; neutral wire.</li>
<li>We push S3 button and it's NC contact interrupts all the circuits, stopping the motor.</li></ul></li>
<li>To supply motor's reverse, the main wires should be changed by place on 1 and 5 or 2 and 6 terminals on any contactor (phases A and C).</li>
<li>NB! To construct this circuit you should really be 100% sure what you are doing in your own safety purposes! If you are not sure, ask the help from specialist!</li></ul>
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