Nikon DTM-302 Series, Instruction Manual

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Checking and Adjustment 6
Total Station DTM-302 Series Instruction Manual 165
To check the instrument constant, you can either compare a correctly measured base
line with the distance measured by the EDM, or follow the procedure below.
To check the instrument constant:
1.
Set up the instrument at Point P, in as flat an area as possible.
2. Set up a reflector prism at Point Q, 100 m away from Point P. Make sure that
you take the prism constant into account.
3.
Measure the distance between Point P and Point Q (PQ).
4. Install a reflector prism on the tripod at Point P.
5.
Set up another tripod at Point R, on the line between Point P and Point Q.
6. Transfer the DTM-302 instrument to the tripod at Point R.
7.
Measure the distance from Point R to Point P (RP), and from Point R to Point Q
(RQ).
8. Compare the value of PQ to the value RP + RQ. The difference should be within
the specified range of error for the instrument (±3 mm + 2 ppm × distance).
9.
At 100 m distance, the error range is ±3.2 mm. If the error is out of range,
contact your dealer.
10. Move the DTM-302 to other points on the line between Point P and Point Q.
11.
Repeat Step 5 through Step 10 several times.
About 100 m
P Q
P R Q