Hitachi VTMX900ECT Wartungshandbuch Seite 7

TOOLS FOR ERROR DIAGNOSIS
Replacement procedure
components (chip)
The following procedures are recommended for replacing leadless
components used in this unit.
1. Preparation for replacement
a. Soldering iron
Use a pencil-type soldering iron that uses less than 30W.
b. Solder
Use Eutectic solder
(Tin 63%, Lead 37%)
c. Soldering time
Maximum 4 seconds.
Note:
a. Leadless components must not be re-used after removal.
b. Excessive mechanical stress and rubbing of the component
electrode must be avoided.
2. Removing the leadless components
Grasp the leadless component body with tweezers and alternately
apply heat to both electrodes. When the solder on both electrodes
has melted, remove leadless component with a twisting motion.
Note:
a. Do not attempt to lift the component off the board until the
component is completely disconnected from the board with a
twisting motion.
b. Be careful not to break the copper foil on the printed circuit
board.
Chip
Soldering iron
Fig. 2-1
for leadless
Tweezers
3. Installation of leadless components
a. Presolder the contact points on the circuit board.
Presolder
Fig. 2-2
b. Using tweezers press down the part and solder both electrodes
as shown below.
Fig. 2-3
Note:
Do not glue the replacement component to the circuit board.
How to remove/install the FLAT PACK IC
1. How to remove the Flat Pack IC
• Using a hot air Flat Pack IC unsoldering equipment
Fig. 2-4
Soldering iron
Tweezers
Soldering iron
solder
EXAMPLE
2-1
GB