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Repair and Repl acement Procedures 7-36 ProMa ster 25 00 U ser Ma nual The pin insula tion block is s ymmetrical so no s pecific polarity orientation is req uired; it may be inserted into the prog ramming block either wa…
Repair and Replacement Procedures
ProMaster 2500 User Manual 7-35
2. Using the needle nose pliers, insert the replacement pin in the same
hole in the block.
3. To ensure that the pin is seated correctly, use the pliers (or flat end of
a flat-blade screwdriver) to press down on the spring-loaded pin
until it is flush with the block. Do not use any object to push the pin
farther down the hole.
4. Continue replacing any other questionable pins, and then test the
module by running a device-related operation on the system.
Replacing the Pin
Insulation Block
After a high number of device insertions in the programming module, the
holes in the pin insulation block may become enlarged or elongated. This
increase in hole size may eventually allow too much movement of the
module pins while a device is being inserted, resulting in a higher
number of continuity test and device programming errors. If you
experience a gradual increase in these failures, examine the insulation
block for enlarged pin holes.
If you determine that the pin insulation block needs to be replaced,
perform the following steps.
1. Remove all module pins (gold spring-loaded pins) from both pin
insulating blocks.
2. Turn the module upside-down and remove the two recessed Phillips
screws that hold the programming block to the circuit board.
After the screws have been removed, the programming block will
still be held to the board by the physical tension caused by the two
alignment pins.
3. Pull the board straight up and away from the block.
4. Remove both pin insulation blocks from the programming block with
a pair of needle-nose pliers.
5. Insert two new pin insulation blocks.
Figure 7-26
Replacing the Defective Pins
1930-1
PRINTED
CIRCUIT
BOARD
Repair and Replacement Procedures
7-36 ProMaster 2500 User Manual
The pin insulation block is symmetrical so no specific polarity
orientation is required; it may be inserted into the programming
block either way.
6. Carefully plug the programming block onto the circuit board using
the block’s alignment pins as guides.
The programming block is symmetrical so no specific polarity
orientation is required; the block may be inserted on the circuit board
either way. The block is seated on the board correctly when rests
against the board on all sides without a gap. If a gap exists, remove
and reseat the block.
7. Turn the module upside down and reinsert the two Phillips screws
on the bottom of the circuit board.
8. Reinsert the spring-loaded module pins in the insulation block.
Note: One end of the module’s gold contact pin is spring-loaded and telescopes
when pressed. Reinsert the module pin into the new insulation block with
the telescoping end up so that end contacts the device lead during
programming.
Most SOIC programming modules ship without some pins in the pin
insulation block at the narrow end of the module board. Start
reinserting pins in the block holes nearest the wide end of the circuit
board and work toward the narrow end. Fill both insulation blocks
with an equal number of module contact pins. Figure 7-27 shows a
device over the pins at the wide end of the board.
9. To ensure that the contact pin is seated correctly, use the pliers to
press down on each pin until it is flush with the module’s top surface.
Do not use any object to push the pin farther down the hole.
Figure 7-27
Pin Insulation Block in the Programming Module
2280-2
PIN INSULATION
BLOCK
PROGRAMMING
BLOCK
CIRCUIT BOARD
FRONT
OF
HANDLER
DEVICE
Repair and Replacement Procedures
ProMaster 2500 User Manual 7-37
10. Test the module by running a device-related operation using the
module.
Replacing the
Programming Block
on a PLCC Module
After a period of time, the protective coating on the programming block
(see Figure 7-28) may wear to the point that you begin to see a higher
number of device-related errors. If you have a second module of the same
pin count, you can confirm that wear is the source of these problems by
programming the same type of device on the second module and
comparing the yields.
CAUTION: To avoid possible damage to the system components, this
procedure should be performed only by a qualified service
technician.