
Lake Shore Model 340 Temperature Controller User’s Manual
11-10
Service
Transformer Assembly Screws
M340SV
U146
M340MN
U26
NOTE:
If you only have two inputs, then you do not have an option card installed. You may skip to Step 10. If
you have more than two inputs, then you have an Option Card installed. Please perform the actions in
Steps 6 thru 9.
6. Remove the ribbon cable which plugs into the Option Card plug (J3) located on the lower right corner of
the card.
7. Remove the four smaller Phillips head screws which secure the board to the stand-offs. These can be
found on the side opposite the sensor plug and on the edge close to the J3 ribbon cable plug.
8. Remove the two Phillips head screws that secure the Option Board to the Model 340 rear panel.
9. The option board now can be lifted out.
CAUTION
: The EPROM is an Electrostatic Discharge Sensitive (ESDS) device. Wear shock-proof wrist
straps (with a resistor that limits current to <5 mA) to prevent injury to service personnel and to
avoid inducing an Electrostatic Discharge (ESD) into the device.
10. Note the orientation of the notch on the M340MN Flash Memory (U26) and M340SV EEPROM Memory
(U146) chips. Gently pry the chips from both ends. Once removed, install the new memory chips with the
same notch orientation. Press firmly on the center of the chip for good socket connection.
11. Inspect the newly installed chips for bent pins or improper alignment. There should be a pin for every
socket hole. Verify the notch orientation.
12. Replace the Option Card (if present). Replace, but do not secure, the cover.
13. Plug in the power cord and turn ON the instrument. If the unit powers up and works normally, the update
is successful. Use the options key to check firmware revision information for both Master and Input
processors. The REVISION INFORMATION SCREEN shows the current version of the Model 340.
14. If there are any problems, unplug the instrument and open the cover. Inspect the chip pins and notch
orientation. Press firmly on the center of the chip to ensure it securely engages the socket. Replace cover
and retry. If unsuccessful, contact the Lake Shore Instrumentation Service Department.
15. Upon successful update, power down the instrument, replace the rear plastic bezel, and replace and
tighten all cover screws.