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©2008 Johnson Level & Tool
7. Self-Check and Calibration
Accuracy Self-Check - Plumb point accuracy self-check
1. As shown in figure 1, put the unit on the ground in the direction shown in
figure 1-1.
2. Power on the unit and mark the center of plumb-down as point “E” and
plumb-up point as “A”.
3. Turn the unit 90° (as shown in figure 1-2) and place the down beam on
the “E” mark. Mark the center of the plumb-up point as “B”.
4. Turn the unit 90°again (as shown in figure 1-3) and repeat step 3. Mark
the center of the plumb-up point as “C”.
5. Turn the unit 90°again (as shown in figure 1-4) and repeat step 3. Mark
the center of the plumb-up point as “D”.
6. Marks A-D should all be in the same spot. If not, the unit will need to be
recalibrated. Please see calibration adjustment information.
IMPORTANT:
It is the responsibility of the user to verify the
calibration of the instrument before each use.
Figure 1
E
1-1
1-2
1-3
1-4
1282H-English 6/11/08 11:37 AM Page 8
