Module 2: Excitation reduction at source and factors affecting vibration level
Lecture 6: Field Balancing
For balancing of a rotor one needs three trest runs and measure the amplitude and phase of vibration at two different locations 1 and 2.
At first, amplitudes and phases corresponding to unbalanced rotor at locations 1 and 2 denoted as
and
are measured.
Next for a trial mass the
same are noted. Let these be
and
Finally, in the third run, for a trial mass
one needs to obtain
and
One can show that the balancing masses required are
and
where,
where,
and 
are measured.
same are noted. Let these be 
and 
one needs to obtain 
and 
and 
where, 
