LI-COR 6400-926 User manual

6400-926
LI-6400/6400XT Portable
Photosynthesis System
LI-6400/6400XT Portable
Photosynthesis System
Digital Board Upgrade Kit
Installation Instructions for LI-6400XT Upgrade
Before You Begin
The LI-6400’s digital board contains, among other things, some instrument specific calibration
files. Therefore, before changing digital boards, it is necessary to download these from the old
board, and then upload them onto the new board once it is installed. In addition, you may have
data or configuration files that you want transferred from the old memory board to the new one.
Do the following steps to accomplish these transfers:
Windows Instructions
1. Install the LI-6400 File Exchange program (if you have not installed it previously).
Place the LI-6400 Software CD in your PC. If it is not there already, select “LI6400 Applica-
tions” in the drop-down menu under Install PC Software (Figure 1).Then click on the ‘Go’
button.
Figure 1. Choose‘LI6400 Applications’ and click ‘Go’ to install the File Exchange software.
2. Connect the LI-6400 to a PC
This requires the 9975-016 cable that is shipped with the LI-6400 (Figure 2).
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Computer
9 pin AT
LI-6400 9975-016
9975-016 Adapter Computer
9 pin AT
9 pin AT
LI-6400
25 pin DTE
Figure 2. Typical cable connections.

3. Put the LI-6400 into File Exchange mode
From power on, press escape when asked if the chamber/IRGA is connected.This will get you to the LPL screen.Then
press Xto enter file exchange mode.
4. Run LI6400 FileEx
You can launch it from the Windows Start Menu/Programs. If the LI-6400 is connected to COM1 on your computer,
communication between the LI-6400 and the computer will be established automatically (if the ‘Connect automatically
when program runs’ check box is enable in the dialog below). If the instrument is connected to a different serial port,
go to the File Menu, select Prefs, and choose the correct communication port.
5. Transfer the calibration files
The calibration files /dev/parm0 and /dev/parm1 do not appear in the normal file system, but they are accessible via the
File Exchange directory listing, as shown in Figure 3 below.
Locate the User/dev directory in the LI-6400 File System window and highlight parm0 and parm1. Choose a directory
on the computer to which these files will be sent, and click on the left arrow button below the LI-6400 File System
window to move the parm0 and parm1 files.
Figure 3. Saving /dev/parm0 and /dev/parm1.
1. Highlight parm0 and
parm1...
2. and then click here to
move the files
]
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6. Save any data files you might need
Open the User directory on the LI-6400, and copy any data files you might want, if you haven’t done this already. Once
you pull the board from the LI-6400, you will not be able to retrieve these files without re-installing the board.
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7. Save any configuration files you might need
If you have some custom configuration files (favorite displays, custom autoprograms, etc., you may want to copy them
from the old board, and install them on the new board.
NOTE: If you can regenerate
these files on the new digital
board (by using the installa-
tion menu, for example), we
would recommend that you
do that, instead, as old
Compute lists will not be
“Excel-friendly”.

Disassembly and Reassembly
A. Removing the PC Boards
1. Power the LI-6400 off, and disconnect all cables and batteries
2. Assemble the tools shown below; be sure to use the disposable grounding wrist strap (not pictured) before
opening the LI-6400 console case or beginning the installation procedure.
3. Remove the console bottom shell
There are 8 screws on the front and rear panels that must be removed. Remove the batteries from the shell; the
old shell will not be re-used, and can be discarded. Make sure to loosen the 4 spring-loaded screws on the
bottom of the shell; remove the plate that has the rubber feet attached and install the plate on the new shell.
4. Unplug the display and keyboard connectors
Unplug the keyboard connector by carefully lifting it up from the pins on which it sits (Figure 6).Then, unplug
the display connector on the other side of the console (B). Finally, if there is one, unplug the back light connec-
tor (C).
Phillips head screw-
driver (#1 or #2)
11/32" nut driver
11/32" open end wrench
Diode circuit
Needle nose pliers
Kep nuts, star
washer, and
screw
NOTE: The 11/32” nut driver and open
end wrench are required only when
installing the diode circuit. Your
instrument may have the diode circuit
installed already; if so,you can skip the
instructions on page 7 (Installing the
Diode Assembly). See page 7 for
location of diode assembly.
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Figure 4. Unplug the keyboard connector
by lifting straight up; be careful not to bend
the ribbon cable attached to the connector.
Keyboard connector
Backlight connector
Figure 5. Turn the console around and unplug
the display and backlight connectors (if
present).
Display connector

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5. Turn the console upside down and disconnect all flow board connectors
All of the connectors in question go through a square hole to the flow board (Figure 6).
Figure 6. The underside of the console, showing the connector well from which all 5 connectors should be
unplugged, and the location of the 4 screws that should be removed that hold the board assembly in place.
6. Remove the board assembly retaining screws
There are 4 whose locations are shown by the red circles in Figure 6.
7. Unplug the board assembly
All of the boards in the assembly connect to the back plane board at the right end of the console. Unplug these
boards by hooking your fingers on the standoffs on the back of the assembly and pulling (and rocking back and
forth gently) the assembly out of the connectors (Figure 7).
Figure 7. Unplug the board assembly from the back plane board by pulling (and rocking side to side gently) on the
board stand-offs.
Back plane board
Pull here

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8. Slide the board assembly out of the console
Be careful that the display and keyboard cable and connectors don’t snag on the boards as you slide them out of the
console.
Figure 8. 6400-926 Digital Board.
9. Use a 7/64” hex key to remove the 4 hex head screws at the locations shown by red circles in Figure 8. Remove the old
board and discard. Install the new board in the board assembly using the 4 hex head screws.
B. Re-installing the PC Boards
1. Slide the new board assembly back into the console
Be careful not to snag the keyboard and display connectors and cables.
2. Re-connect the keyboard, display, and backlight (if present) connectors
Make sure the connectors are centered, especially the display connec-
tor (Figure 9). If you are off a pin to the left or right, you can do
serious damage when you turn on the power. There are white lines on
the board that help align the display connector (see at right).
Figure 9. Be especially careful to get the display connector centered. If you don't,power on might cause damage.
Backlight connector
Display connector
Keyboard connector
TOO HIGH
Make sure both
rows of pins are
plugged in.
TOO FAR
LEFT
Powering on will
destroy a part
on the board.
CORRECT
TOO FAR
RIGHT
Doesn't do
damage, but it
also won't work.
Alignment lines

3. Re-seat the board assembly
Line up the edge connectors of the three boards, and push them into the back plane board by pushing on the
standoffs between the boards.
4. Install the retaining screws
Turn the console over, and re-install the four screws. The board assembly has to be fully seated before the screw
holes line up.
5. Reconnect the flow board connectors
Refer to Figure 10 below. Note the labels on the flow board by each connector.
Figure 10. Diagram for plugging in connectors to the flow board. On instruments that do not have a CO2
injector, the pump connector is left empty. The pump plugs into the CO2injector connector, instead.
P ATM
With CO2Injector
Without CO2Injector
PUMP
BOX FAN
FLOW METER
CO2 INJECTOR
Red/Green Red
Red Red
Orange
White
Blue
Blue Black
Black
P ATM PUMP
BOX FAN
FLOW METER
CO2 INJECTOR
Red Red
Red
Orange
White
Blue
Blue Black
C. Installing the Diode Assembly (if needed)
The diode assembly is required with the new digital board for signal noise suppression. Your instrument may
already have the diode installed; if so, skip this section. The diode is located internal to the two battery connec-
tors, as shown below in Figure 11.
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Diode assembly
Figure 11. If present, the diode assembly can be found on the ground lug internal to the two battery connectors.

If the diode assembly is not present, ollow these steps to install the diode assembly, if needed:
1. The diode circuit will be installed on the underside of the card cage, nearest the right side of the console that contains
the power and sensor head connections. It is installed between the ground lug on the LI-6400 case and the black
wiring attached to the negative power input.
Ground lug
2. Use the 11/32" nut driver (or equivalent) to remove the nut from the ground lug, as shown below. This nut will
not be reinstalled; a kep nut included will be installed in its place.
3. Carefully remove the ring terminal from the ground lug and move the terminal away from the lug slightly, as
shown. IMPORTANT: the wire leads on the capacitor are fragile and can break easily. Do not bend these leads
back and forth or stress them in any other manner. Leave the star washer on the ground lug.
Remove
this nut
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4. Note the position of the ring terminals on the diode circuit. One of the terminals should be nearly perpendicular to the
diode, while the other is angled slightly; the ring terminal that is perpendicular to the diode is installed on the ground
lug, and the other terminal is mated to the existing ring terminal on the capacitor. These ring terminals on the diode
circuit can be bent slightly if needed to facilitate mating to the capacitor.
Capacitor leads
are fragile. Do
not bend or
stress.
Diode circuit ring
terminals. Note that this
terminal is nearly
perpendicular to the
diode.
5. Install the diode circuit over the ground lug, on top of the existing star washer. Install a kep nut onto the
ground lug to secure the diode circuit. Hold the diode circuit in place and tighten the kep nut using the 11/32"
nut driver.
6. Use the needle nose pliers to carefully bend the diode circuit's top ring terminal to match the angle of the
battery ground's ring terminal, so that the two can be mated with the screw. Again, be careful not to stress the
capacitor leads on the battery ground's circuit. Install the supplied screw through the two ring terminals; use a
star washer between the ring terminals, as shown. It may be helpful to hold the star washer with the needle
nose pliers while performing this step.
Install the diode circuit
over the ground lug and
attach a kep nut.
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Install a kep nut onto the screw. Hold the kep nut with the needle nose pliers while turning the screw.
Install the screw through
the ring terminals, with a
star washer in between.
Install a kep nut onto the
screw.
7. Use the 11/32" open end wrench to hold the kep nut, and tighten the screw.
8. Final visual inspection. Make sure that there is plenty of clearance between the newly installed diode circuit and any
other components; the wiring must not touch anything else.
Use the 11/32" open end
wrench to hold the kep
nut while tightening the
screw.
Make sure the wiring and
connection points are not
touching the case or any
other component.
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