We have had a look at motor testing on the three phase motors and I think we should also have a quick look at the single phase connection diagram. There are a number of single phase motors on various pieces of equipment and what I will try to do here is to explain it as easily as possible.
Let’s start with the basic diagram of the motor connection. Now you will see people will draw this in all sorts of methods but I will show you a very simple way of doing it.
To understand the circuit, you need to know how to find the two windings of the motor. These are your starting winding and the running winding. The way to determine which is which, is to measure the resistance of the winding. Use your multimeter and set it to the ohm scale. Now measure the resistance of each winding and write it down. The highest reading you obtained is the starting winding and the lower reading is the running winding.
Now look at the connection based on the diagram below:
You will see that one end of the run winding and one end of the capacitor is connected to the Active or “Live”
The other side of the capacitor is connected to one end of the start winding
The other end of both the start and run windings now gets connected to the Neutral
All done, you can now run the motor.
So now the motor runs but in the wrong direction. How do we change that?
Again, there are two ways of doing that. You can change either the starting OR running winding connection around. Never do them both or the motor will still be running in the wrong direction!
In the sketch below I show how to swop the start winding around. As a habit, I always do the start winding but you may choose your own way of doing it.
You will note the sketches are drawn pretty rough but the result is what we are after. This is typically the sketch I would make when having to connect a single phase motor.
And again, as always, I hope you find this useful and remember to always think before you do! There is no substitute for SAFETY!
By Single Phase Motors « sparkyhelp March 2, 2012 - 3:00 am
[...] inside the terminal box that, in some cases, make no sense at all. This prompted me to share the basic diagram that I scribble on a piece of paper and use as my connection tool. Nothing fancy though, but you [...]
By Vinay June 13, 2012 - 4:26 am
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By Henal September 16, 2012 - 12:17 am
so as we are testing the motor there should be no shorts between the start winding and run winding then cut from the live and nutural wires
By Tom October 20, 2012 - 1:17 pm
how can i change direction if only 3 connection out side the motor.
By Francois Korf October 25, 2012 - 11:41 am
Hi Tom
This will be an issue for you as the manufacturer has joined the one end of the starting and running windings inside the motor which means you are not able to change the start winding around. If you could send me a sketch of what you have I could look at it but this may not be possible
Regards
Frans
By anjali November 24, 2012 - 5:50 am
if we connect two heaters in series or parallel then what will be the effect on heat produced
By rushit d patel January 24, 2013 - 4:33 pm
when motor running wrong direction which connection i want to change.which winding wire change or i want to know capacitor is connected in starting winding or running winding
By Francois Korf February 3, 2013 - 11:18 am
Hi Rushit. To change the direction of a single phase motor you can change either of the two windings around but not both. I normally change the start winding and to find out which winding it is, test the continuity of each winding. The winding with the highest resistance is the startin winding. Hope this helps. If not, please send me an email and I will try to assist
Regards
Frans
By rushit d patel January 24, 2013 - 4:35 pm
i want to connection diagram of motor running in wrong direction and motor running in actual direction also i want to know capacitor connect in starting winding or running winding pls reply brefely.