Spectra Precision DG613 Information Guide

Method 1: Using the Top Pole Scale (TPS)
Grade rod set on top of the Universal Fixed Pole.
Note: You must first decide what elevation the laser beam shall be used above the invert!
1. Record the “cut-to-invert” information from the grade hub.
2. Set up an automatic level and measure the elevation (HI) of the automatic level above the
grade hub.
3. Set a grade rod on top of the 1239 Universal Fixed Pole and record the measurement with the
automatic level.
4. Subtract the desired elevation of the laser beam above the pipe’s invert.
5. Calculate the TPS (Top Pole Scale) setting.
6. Adjust the pole clamp until the reading edge equals TPS.
7. The laser is now at the proper working elevation.
Laser beam distance
above invert
Rod reading on top
of fixed pole
Rod reading
on grade
hub
Cut to invert
Surveyor rod
Grade hub

Spectra Precision DG613 Specifications

General

Brand	Spectra Precision
Model	DG613
Category	Measuring Instruments
Language	English