#0-313A-SBA (6/01)
Page 13 of 14 pages
BARRETT CENTRIFUGALS INC.
1-800-228-6442
PLUMBING THE SPINDLE AND MOTOR BALANCING SPRING ADJUSTMENT
The balancing spring system is properly set up and plumbed at the factory. If your machine
is installed level no adjustment should be necessary. After extended use the springs may
need adjustment.
Proper tension of the balancing springs is imperative to insure a smooth running and well-
balanced machine. Excessive spring tension will cause unnecessary wearing of the pivot
assembly by excessive restriction of the oscillation. This will cause pounding and vibration,
which will transmit undue stress and strain to the spindle bearings, thereby shortening the
bearing life.
NEVER ATTEMPT TO ADJUST THE BALANCING SPRINGS WHILE THE MACHINE IS
RUNNING!!
To plumb the spindle, remove tension from the four balancing springs by backing off the jam
nuts. Plumb the rotating element using a level on top of the flat machined surface of the
carrier or pan support. Screw the bottom four nuts down until they bear lightly and evenly on
all four springs and the carrier registers plumb. (Tension at this point should be such that the
springs can be turned by hand.) Then tighten each nut two full turns and set the jam nuts
securely.
ROTATION DETECTOR
(Refer to Fig. 3)
The rotation detector is a PNP diffused mode photoelectric sensor mounted in the bottom
motor housing of the machine. It senses rotation by emitting light toward a
Fig. 3.
Rotation detector
notched cylinder attached to the bottom of the rotor and sensing the amount of light reflected
back. The sensor’s sensitivity is set at an optimum level at the Barrett factory. It should not
require adjustment. However, if it seems to be malfunctioning, check the following:
