OHAUS EXPLORER, Service Manual

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CHAPTER 3 REPAIR PROCEDURES
3.2 REPLACEMENT OF MAJOR COMPONENTS
When using this section of the Service Manual, you will find it necessary to refer to other sections. References are made
to the Exploded Views which are located and identified in Chapter 5, Drawings and Parts Lists.
The decision to replace any component should only be made after thoroughly diagnosing the problem.
If, after the replacement of any component, the balance is still nonfunctional and no other information on the subject is
available in the manual, contact:
Ohaus Corporation
19A Chapin Road
P.O. Box 2033
Pine Brook, NJ 07058-2033 USA
Tel: 973-377-9000
Fax: 973-593-0359
In the United States call toll free, 800-526-0659 between 8:00 a.m. and 5:30 p.m. EST.
3.2.1 Analytical Balances Main Printed Circuit Board (PCB)
See Figure 5-2 for steps 1 through 4.
1.With the balance turned OFF and unplugged, open the Draft Shield door and remove the Pan (5).
2.Remove Cover Plate (6).
3.Inside of the Draft shield, remove two Screws (2) and Lockswitch Cover Seal (1).
4.Carefully lift the Draft Shield from the balance Base and set aside.
See Figure 5-3 for remaining steps.
5.Remove two Screws (3) which secure Shield (4) in place.
6.Remove Shield (4) from the balance.
7.Remove the two Screws (3) on top of the PC Board (11).
8.Remove the Hex Screws (14) and Washers (25) at the rear of the balance which secure the connectors on
the PC Board (11).
9.Disconnect the two cable connectors from the Load Cell going to J3 and J6 on the PC board as shown on
Figure 5-3.The Load Cell (9). If internal calibration option is installed, disconnect cable to J4.
10. Carefully lift the PC Board (11) from the Base (18) there is a small cable from the Sensor Board which should
also be disconnected from the PC Board (not shown on Figure 5-3).