Agilent Technologies 6890 Series Service Manual page 433

430 Power/Electronics Replacement
Replacing the main board
P19
P21
P22
After disconnecting the EPC ribbon cable (P3) and AC Power harness
(J7), pull them back through their slots and out of the way.
Beeper
P1
P11
GND
P12
Oven Access
GND
Cutout
P13
P17
3V
Lithium
battery
4 ROM
Sockets
Figure 430-1
2 of 26
AC board control
Inlet/Detector heated zones — Remove the Inlet/
Detector wiring harness connectors from the
main board sheet metal bracket.
Valve box and aux heated zones
P16
P2
DSP
Gate
Array
CPU
+15V
–15V
+5v
Gate
Array
Main board connectors, 6890A and 6890 Plus
Mainframe
Agilent 6890 Gas Chromatograph Service Manual
P21
P3
P22
P15
P18
F2 F1 F4 F3
J7
Hole for
transformer
cable
P19
Capacitors
Capacitor
J1
J2
JP1
JP2
J8
J4
J6
–24V
+24V J5
Jun 2001