R2W PLUS
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5. Check and Adjustment
5.1 The Instrument Constant
1) Check
It is suggested to observe and compare the instrument with a testing line which is set on
stable ground with a particular accuracy, though error is not generally included in the
instrument constant. If the testing line is unavailable, you can set it for 20 meters or so by
yourselves, then check and compare it with your new instrument.
1. Select a point B on the approximately horizontal line AC with about 100 meters long.
Measure the distances of lines AB, AC and BC.
2. The instrument constant can be calculated:
instrument constant =AB+BC-AC
3. If there is a difference between the instrument standard constant and the calculated
value, colligate the measured constant and the prism constant to get a new value, then
input the value into the instrument as a prism constant .
4. Compare length of the instrument’s testing line again with a certain standard testing
line .
5. If the difference is over 5 mm after the preceding operations, it is necessary to reset the
instrument constant .
2) Adjustment
About instrument constant setting, you must contact STONEX distributor to do that.
A
B
C
AB
BC
AC