A PAM winding is a way of building the winding coils in electric motors. PAM stands for Pool-Amplitude Modulation. PAM-powered motors, which are manufactured by Siemens, among others, are so-called pole-changeable motors and have the special feature that incremental speed changes are possible.
Motors with a PAM winding offer several advantages over the conventional motors with pole switching. They are cheaper, lighter and easier in maintenance than motors with two separate windings. In addition, motors with a PAM winding include, among other things, a more flexible gear ratio than motors with a winding with Dahlanders circuit.
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