Disassembly And Service Procedures; Fuse Replacement - DENTSPLY Cavitron JET Plus Installation And Service Manual

SECTiON 19:
Disassembly and
Service Procedures
CAUTION: THIS UNIT CONTAINS COMPONENTS
WHICH ARE SUBJECT TO ELECTROSTATIC DISCHARGE
(ESD) DAMAGE. THE WORKSTATION SURFACE AND
REPAIR TECHNICIAN MUST BE PROPERLY GROUNDED
PRIOR TO REMOVAL OF THE COVER.
iNDEX
A. Top Cover Removal
B. Fuse Testing Procedure
C. Fuse Replacement
D. Handpiece Cable Assembly Replacement
E. Water Solenoid/Regulator Replacement
F. Power Supply Assembly Replacement
G. Power Drive PC Board Replacement
H. Information Center PC Board Replacement
I. Main Controller PC Board Replacement
J. Air Manifold Assembly Replacement
K. Pinch Valve Replacement
L. Pinch Tube Replacement
M. Air Manifold Connections
A Top Cover Removal:
1. Power off the Cavitron
rocker switch.
2. Unplug the Power Cord from the rear receptacle.
3. If the auxiliary Foot Pedal cable was being used,
disconnect it from the rear of the unit.
4. Disconnect the blue water hose by unplugging the
quick disconnect at the supply. Depress the tip of the
quick disconnect in a suitable container to relieve the
water pressure.
5. Turn the Cavitron JET Plus unit over. Place it on a
®
clean non-abrasive surface to prevent damage to the
Top Cover.
6. Use a screwdriver and remove the six #6 x 1/2" Hi-Lo
recessed screws located along the front and back of
the unit.
7. Support the Top Cover against the Bottom Housing
and return the scaler to the upright position. Collect
and save the six screws for re-assembly.
8. Lift the Top Cover from the front and support it
adjacent to the Bottom Housing to prevent damage to
the ribbon cable.
JET Plus unit using the front
®
B Fuse Testing Procedure:
White Wire
1. Follow this procedure to test the condition of fuses,
F3 and F4, without removing the protective cover on
the power entry module.
2. Unplug the power cord from the rear Power Entry
module.
3. Follow the steps above in Section A for "Top Cover
Removal".
4. Ensure that the Power Switch is in the ON position.
5. Use a DVM in the Resistance "Ω" setting to measure
the continuity.
6. Place one probe on the LEFT terminal of the Power
Entry module.
7. Place the other probe on the WHITE wire connector at
the front of the Power Supply assembly.
8. If the DVM reads continuity, the F4 fuse is good.
9. Repeat Steps 6 thru 8 to test fuse F3 using the RIGHT
terminal of the power entry module and BLACK wire.
C Fuse Replacement:
1. Follow the steps above in Section A for "Top Cover
Removal". Ensure that the power cord has been
unplugged from the rear power entry module.
2. The Power Drive PC board is mounted vertically in the
left-rear of the base cabinet. Unplug the Top Cover
ribbon cable at J5 on the Power Drive PC board and
place the Top Cover to the side. Unplug the power
supply harness from J1 on the Power Drive PC board.
3. Remove the plastic barrier from the center of the unit.
Pull the plastic barrier away from the heatsink to
release the two-sided tape and lift the barrier out of
the unit.
4. Use a screwdriver and remove the two #8 x 1/2
Hi-Lo screws at the base of the heatsink bracket.
Work carefully to prevent damage to the Power Drive
PC board components.
5. Use a screwdriver and remove the two #6 x 1/2" Hi-
Lo screws located at the back corners of the Power
Supply assembly.
6. Tilt the Power Supply assembly up to allow the Power
Drive PC board to be lifted out of position. Use care
not to damage connector J7. It is mounted on the
back of the Power Drive PC board and protrudes
through the rear cabinet housing. This will allow
access to the power entry cover.
7. Use a screwdriver and remove the #6-32 x 3/8" screw
on the Power Entry cover.
37
Black Wire