Removing The Component Covers And Lifting Out The Cable Plugs; Removing/Replacing The Main Printed Circuit Board (Pcb) - OHAUS Valor 2000 Service Manual

3.3.2 Removing the Component Covers and Lifting Out the Cable Plugs

Load
Cell
Cover
Rear
Display
PCB
Cover
Figure 3-4. Top and Bottom Housings with some plugs removed.
1. Remove the screws that secure the cables to the housing, to avoid straining the
cables when loosening the plugs.
2. Firmly grasp the plugs and lift them clear of the component covers. (Don't try to
remove them completely until they are disconnected from the PCBs.)
3. Remove the screws that secure the component covers to the housing. The PCB
covers on the Top Housing must be removed before the Load Cell Cover, to allow it
to clear. Only remove the Power Supply Cover if the Power PCB is to be replaced.
3.4

Removing/Replacing the Main Printed Circuit Board (PCB)

The Main PCB must be removed in order to replace the Load Cell, since the Load Cell Cable is
soldered to the Main PCB. First be sure the eight screws securing the PCB Cover have been
removed and that the cable plugs have been lifted out. Then proceed as follows:
1. Pull the two white Cable Tabs that connect the Main PCB to the Power PCB and the
Rear Display PCB. (It is necessary to hold the PCB Cover by hand at an angle while
pulling the Cable Tabs. Once the Cable Tabs are freed, the PCB Cover can rest slightly
away from the PCB, allowing access to the screws that hold the PCB in place.)
2. Remove the four screws that hold the PCB in place. (It is necessary to hold the
screwdriver at an angle in order to access the screw heads.)
3. If either the Main PCB or the Load Cell is to be replaced, unsolder the Load Cell Cable
from the Main PCB at the four solder points on the PCB.
4. When replacing the Main PCB, solder the Load Cell Cable leads to the solder points on
the PCB. Note the connection order from left to right: red, black, green, white.
5. To reinstall the Main PCB after soldering the Load Cell leads, position the PCB on an
angle in its housing, insert the four screws and tighten them.
6. Re-seat the white plastic Cable Tabs connecting the Power PCB and the Rear Display
PCB to the Main PCB.
7. Position the PCB Cover over the screw holes, insert the eight screws and tighten them.
8. Re-insert the Cable Plugs in the PCB Cover.
Valor™ 2000 Series Service Manual
CHAPTER 3 MAINTENANCE PROCEDURES
Main PCB
Cover
3-3 Ohaus Corporation www.ohaus.com
Power
PCB
Cover