OHAUS CKW3R, Service Manual

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CHAPTER 3 MAINTENANCE AND REPAIR PROCEDURES
3.3 Setting the Overload Stops
The Overload Stop gaps must be checked and reset if the Load Cell is replaced. This
procedure requires two test masses: one equal to the base’s capacity, and one equal to 150%
of its capacity. (To check capacity, refer to the Specification Table in Section 1.7.)
There are six screws in the Lower Housing of the Base. Each is capped with a round Overload
Stop Nut and a Jam Nut. (See Figure 3-1.)
To adjust the Overload Stops:
1. Apply 100% load at each corner stop, one at a time; adjust the round Overload Stop Nut
and lock it with the Jam Nut when the Upper Housing just touches the Overload Stop
Nut.
2. Repeat this for all four corners.
3. For the two sets of Overload Stop Nuts and Jam Nuts located in the center of the Base,
use a load of 150% of the Base’s capacity placed on the center of the Platform. When
the Overload Stop Nuts are properly set, lock the Jam Nuts in place.
4. Test the Base with Indicator connected to see if full capacity can be achieved.
Overload Stop Nut
Jam Nut
Load Cell Spacer
Load Cell
Figure 3-1. CKW Load Cell, Spacer Overload Stop Nuts and Jam Nuts.
Ohaus Corporation www.ohaus.com 3-2 CKW Base Series Service Manual