DC Machines

Things to remember in a DC Machine

1. EMF equation of a DC motor or generator = (fi*Z*N*P)/60A

Where, fi = flux/pole
             Z= number of armature conductors
             N= Speed in RPM
             P= Number of poles
             A= number of parallel paths i.e A=2 in case of wave winding and A=P(number of poles) in                        case of lap winding
   
     2. Speed = 120F/P

Where f = frequency and P  = number of poles