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Help Wiring Motor - Reversing Starter

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carbitz

Electrical
Jul 8, 2018
2
Hello Chaps

I have inherited a motor with no starter. I have therefore bought a new DOL Starter but i am struggling to connect up. I would be very grateful if any forum members could give me some advise should they be familiar with this setup? It is a single phase motor, and i am trying to add a DOL reversing starter.
 
 https://files.engineering.com/getfile.aspx?folder=212aeb2e-1e33-4e1a-bb3c-b4a614f78c21&file=dol_starter.pdf
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Most single phase motors of that size have a centrifugal starting switch but there are exceptions.
If your motor has a centrifugal switch, it will not be possible to directly reverse the running motor.
It should be stopped before being reversed, however it may be reversed when the speed has dropped enough for the centrifugal switch to close.
Do not remove any of the control wires from the starter.
First, remove the black jumper wires from the bottom of FC to the bottom of the O/L relay, (2-T1, 4-T2, 6-T3)
There are jumpers between the top terminals of FC and RC. Generally they are T1 to T1, T2 to T2 and T3 to T3.
On the bottom of FC and RC T1 generally jumps to T1 but the other jumpers are crossed, T2 to T3 and T3 to T2.
If that is the case, proceed.
The incoming line L1 connects to the O/L relay and daisy chains through all three poles.
Connect L1 incoming to the top left terminal of the O/L relay. Jumper from the bottom left (2-T1) to the bottom center (4T2).
Connect a jumper from the top center terminal of the O/L relay to the top right terminal. From the bottom right terminal of the O/L relay run a jumper to the top left of FC. (L1) from the top left terminal of FC run a jumper to the top left terminal of the top center terminal of FC. Leave the existing jumpers in place.
Connect the incoming L2 to the top right terminal of FC.
Now we are ready to look at the motor connections.
There should be two windings. Use a continuity meter to identify the leads to each winding.
The two leads from one winding connect to the left bottom terminal of FC (T1) and to the top right terminal of RC (L3).
The two leads from the second winding connect to T2 and T3 on the bottom of FC.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
many thanks for responding to the post and your through explanation, I have managed to follow it except "Connect a jumper from the top center terminal of the O/L relay to the top right terminal." I couldn't quite follow this, could you please identify top center terminal and top right terminal?
Secondly i have identified the two windings but do not know which should go where, should i get them in the wrong order, could it be detriment?

many thanks in anticipation.
 
We m,ay have a problem.
If your O/L relay is configured for mounting directly below the contactor (pins) you may have to locate a kit for independent mounting (screw terminals).
With all the black power leads removed from the O/L relay, L1 will have continuity to T1, L2 will have continuity to T2 and L3 will have continuity to T3.

The windings may be interchanged. The point is that the connections of one winding must be reversed in relation to the other winding to reverse the motor..

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
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