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1¡¢Inspect the machine and then open it
(1) Check if the connection wire of the lamp body, the
Temp-sensor and power cable is ok.
(2) Turn on the power switch. Allow the T-870A Power-On-Self-Test
(POST) to complete. After this, Temperature set-points
will display last value used.
(3) The front panel has two switches, controls the preheating
dish and the infra-red lamp body separately;
2¡¢PC Board Component Removal and Replacement
(1) Placed the PCB Board
Put the PCB board on the ¡°PCB board holder¡±, rotate the
¡°holder fasten nut¡±, fasten it. Move the ¡°PCB board holder¡±
to choose the right position.
(2)the Process of unsoldering and repairing
¢ÙAdjust the position of the PCB board, make the chip at
the centre of the lamp light. Adjust the height of the
lamp body, keep the lamp 20-30mm from the chip.
¢ÚPut the temp-sensor at the edge of the chip, lay a bed
of solder flux around the chip and on the temp-sensor,
it will make the measured temperature more accurately,
at the same time the solder flux will make the soldering
chip more perfect, and keep the bonding pad away from
conglutinating and having tin wool.
¢ÛAccording to the producing technological requirement
or the size of PCB board, adjust the pre-heat dish temperature(adjustable
60-200¡æ).
When there is waterproof solid sealing compound on the
chip, please open the pre-heat dish to pulverize the solid
sealing compound first, then clean it up. You may adopt
other method as sol/hydrosol. When you adopt the method
we supplied, you had better choose the temperature between
100¡æ and 140¡æaccording to the producing technological
requirement or the size of PCB board, control the pre-heat
time 3-5 minutes(the temperature will be steady) or longer.
Otherwise if the chip is without waterproof solid sealing
compound or the PCB board is small, then it won¡¯t transmutation,
we needn¡¯t open the pre-heat dish
¢ÜAccording to the producing technological requirement
or the size of chip, choose the suitable temperature of
the IR-lamp.
¢ÝUsually, when the chip size is less than 20*20mm, we
adjust the IR-lamp temperature 220-240¡æ, and if the chip
is without waterproof solid sealing compound or the PCB
board is small, then it won¡¯t transmutation, we needn¡¯t
open the pre-heat dish. Otherwise, we should adjust the
pre-heat temperature to 100-120¡æ.
When the chip is lager than 30*30mm,we should adjust the
pre-heat temperature to 120-140¡æ first, wait 3-5minutes
and the temperature will be steady. Then adjust the IR-lamp
temperature to 240-260¡æ, we will complete the unsoldering
and repairing process conveniently. Attention: At the
time, the light is strong, the temperature rises quickly,
we should pay our attention on controlling, avoid the
Temp-sensor displacement, reflect on the temperature measuring.
We should also pay our attention on time controlling,
avoid burning out the chip.
¢ÞWhen achieving the set-up lamp temperature, Once the
solder liquefied and melted, use tweezers to remove the
chip.
3.the Process of Soldering a chip
It is generally the same as the ¡°(2)Process of unsoldering
and repairing¡±, but you should do as follows:
¢ÙClean the target pad with the brush
¢ÚThen put the solder ball and a flat of solder flux and
the chip on the target pad
¢Û Turn on the switch of the pre-heat dish, and set-up
the temperature
¢ÜTurn on the switch of the IR-Lamp, Regulate the temperature
(the temperature must be warm enough to liquefied the
solder), focus the Infrared light on the chip to be solder
¢Ý Wait to allow the Infrared lamp to heat the solder flux
to work as the solder balls on the target chip pad reaches
liquid temperature. Use tweezers or a vacuum device to
place the chip target position. Once the solder liquefies,
the chip will be sold automatically.
After cooling the chip, pick up the PCB board, check if
it is ok. If not, re-operate.
Suggestion:
About the components without plumbum, you should add 20-30¡æ.
4. the Process of soldering kinds of Plug (as: GAP platoon
expansion slot plug of the computer motherboard)
Usually we cover the hardware and the PCB board (which
won¡¯t be maintained) with the aluminium-foil paper, Then
put the PCB board on the holder, fasten it. Turn on the
Pre-heater dish and adjust the temperature at 160-180¡æ,
Put the Temp-sensor at the side of the part which is being
unsoldering, and it will up to the temperature in 3-5minutes.
Then you can unsoldering the parts.
In special circumstances, you can open the IR-Lamp to
heating the part, and it will be unsoldering quickly.
Suggestion:
About the components without plumbum, you should add 20-30¡æ.
About the PCB board with components on its both side,
please set-up the pre-heat temperature lower, and then
use the IR-Lamp to heat.
5. Cooling the machine
Turn off the switch of the pre-heat dish and the IR-lamp.
Once the machine is cooling enough, cut off the power
cable.
6 Attention
¢ÙWhen you maintain some large chip of the PCB board such
as the mother board of the computer, you must pre-heat
and dry the whole board first, then you can avoid the
transmuting of the PCB board and soldering joint and rake
angle of the chip.
¢ÚAll the plastic plug-in board must be covered with aluminium-foil
paper, to avoid transmutation or destroying.
¢ÛThe PCB board which had been maintained, after cooling,
clean it, and do the test when it is dry. If it is not
ok, re-soldering it.
¢ÜAround working, when the PCB board is not on the holder,
please do not long time open the IR-lamp, do not shoot
the light on the strong glisten objects. Otherwise it
will reduce its using time.
¢ÝAbout the chips which is encapsulation simply, please
pre-stick aluminium-foil paper on the centre of the chip,
to avoid burning out the slice of silicon.
The measurement of the aluminium-foil paper had better
a little larger than the slice of silicon, but not too
large. Otherwise, it will do effect on the soldering.
Maintenance and Warning
Maintenance:
£¡ At all times ¨C Insure the light body cooling fan is
unobstructed and clean.
£¡ Use
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