Sometimes we get complaints from synchronous AC motor users that their’s motor does not work. We can not find the proper reason until we got a picture of her or his power source.
We all know that “+” is positive, “-” is negative. Power source like the pictures below has defined DC clearly.
![](https://chancsmotor.com/wp-content/uploads/2023/05/Power-DC.jpeg)
But the many kinds of power does not make “DC” or “+” “-”, see below
![](https://chancsmotor.com/wp-content/uploads/2023/05/Power-DC-4.jpeg)
![](https://chancsmotor.com/wp-content/uploads/2023/05/Power-DC-2.jpeg)
They have same symbols — and — Let see what is Wikimedia say “An example of the Direct Current symbol”.
And they also have symbol + and -, which distinguish positive and negative of the DC plug.
![](https://chancsmotor.com/wp-content/uploads/2023/05/Power-DC-3.jpeg)
So, all of the power sources which has symbol above should output DC(Directly Current), which will not suit the TYC-40 or 30 synchronous motors.