6. EXCHANGING BOARDS AND MODULES
Service information Phyaction 190 / 190i - Page 17
CHAPTER 5
EXCHANGING BOARDS AND MODULES
5.1 Introduction
The most frequent service operations will be the exchanging of boards or modules, because it would be too
time consuming and costly to do component level service in the field. When exchanging boards or modules
there are a few things that should be noticed. These attention points will be described in this chapter.
If you want to exchange a module or a board you will have to open the appliance. It is probably easy to place
the appliance on its rear side, with the bottom side towards you. You can unscrew the 5 screws of the bottom
plate and tilt it towards you. If you want to test and make measurements you can leave the cables and
connectors where they are, but if you want to exchange a board or module it is better to disconnect the cables
and seperate the bottom plate from the rest of the appliance.
If you have exchanged a board or module, always test the appliance. This functional test starts with switching
the device on and checking the 4 LEDs, the fan and the LCD. If no error messages appear, check the memory
(can you store a setting and retrieve it). Finally check the contact detection of the ultrasound heads. After this
you should do a safety test (short description in section 3.2).
In general it should be said that you should take the necessary precautions to prevent electrostatic discharges
occur on the delicate electronic circuits of the unit. These precautions implicate that you should ground the unit,
use a grounded desk overlay, ground the tools such as solder irons and you should be connected to ground by
the usual wrist or ankle strap.
5.2
Exchanging the software or the main board (PCB 192X)
If you want to exchange the software or the main board of the appliance, you first open the appliance as
described in section 5.1
Introduction
. You disconnect the cable from the transformer to the main board and the
cable of the fan. Then you remove the two screws from the main board, which are located at the back of the
appliance (between the ultrasound module and the back side). You disconnect the cable from the main board to
the keyboard and the cable of the backlight of the LCD. Now you can shift out the board and exchange the
EPROM. If you want you can disconnect the other 4 cables, but that is not really necessary. If you want to
exchange the main board you will have to disconnect the cables from console and from the LCD backlight, take
out the board and disconnect the remaining cables.
If you have exchanged the software or the main board, shift back the PCB on its place and connect all cables.
Also connect the transformer cable. Leave the appliance on its rear side and switch it on. If any error message
appears on the LCD, switch the appliance off and try to repair the cause of the error. After you have succeeded,
you remove the external mains cable and fix the main board with the two screws. Then check whether all
cables are connected (fan !!) and close the case. After you have screwed in the 5 screws on the bottom plate,
you should do a short functional test and a safety test (short description in section 3.2).
5.3
Exchanging the ultrasound module
To remove the ultrasound module, you first remove the bottom plate as described in section 5.1
Introduction
.
Make sure there are no treatment heads connected to the device. The easiest way to place the appliance is
with the front side down. Put it on a soft underground to make sure you don't damage the front side. Disconnect
the internal cable from the safety socket and unscrew the safety socket. Remove the screw to the tab at
R82/C82, then unscrew the three other screws to release the ultrasound module. You can take the module out
of the appliance case, remove the screws from the D-subminiature connector at the back of the module and
disconnect the cable.
If you install a new module there are a few things that you have to pay attention to. You start with connecting
the cable to the module and fixing it with two screws. There are two O-rings between the front panel and the
LEMO chassis parts (the sockets for the ultrasound output) to prevent any liquid from entering the appliance at
that place. Make sure the O-rings are undamaged and are positioned in the chambers around the holes for the
connectors. If you place the module you should make sure the LEDs are positioned in the LED-lenses. Before
you fix the module with the screws you should lift the appliance to make sure the O-rings are still on their place.
