Model 228 Centrifuge User Trouble Shooting Guide
Symptom
Possible Cause
Possible Solution
Unit will not run
No power to unit
Check that unit is plugged in
Check that outlet has power
Rotor loaded improperly
Check that rotor loading is balanced.
Rotor not tightened properly.
Check that rotor fits securely on motor
shaft and that thumb screw is tight.
Unit vibrates
Motor mounting nuts are loose
View bottom of unit and check that the
four nuts that hold the motor to the base
casting are tight.
See “Unit vibrates” section
See “Unit vibrates” section
Unit is noisy
Lid not latched securely
Check that lid is latched. If lid is latched
but not tight, adjust lid latch pawl.
Repair Trouble Shooting Guide
Symptom
Possible Cause
Check
Parts
Wiring
Check wiring connections.
Timer
Check for power in and out of
timer.
Timer; 106868
Lid Interlock
Check that lid latch is
actuating interlock switch.
Check that switch is not
jammed. Check switch
continuity.
Leaf Switch; 67516
Unit will not run
Motor
Check for power to motor.
Check brushes. Check that
motor shaft turns freely.
Motor; 50782 (115V),
50990 (230V),
See User Trouble
Shooting Guide
Damaged Motor
Check that motor shaft turns
freely and does not “wobble”.
Check for shaft “side play”.
Motor; 50782 (115V),
50990 (230V),
Unit vibrates or is noisy
Damaged Rotor
Check that rotor fits securely
to shaft and does not
“wobble”..
Rotor; 50779
Rotor with Shields;
04-978-233
Fisher Scientific Co.
2000 Park Lane
Pittsburgh, PA 15275
Technical Support 1-800-926-0505
Repair Service: 1-800-395-5442
Sales: 1-800-766-7000
Part Number 70906 Rev. F
Operation & Service Instructions
Centrific® Centrifuge 04-978-228 & -229
Published 03/2004
