Spectra DG711 Elevation of Flat Bottom Manholes , 1230/1237 Heavy Duty Invert Plate

5 Applications and Setups
34 DG711 and DG511 Pipe Laser User Guide
Elevation of Flat Bottom
Manholes 5.4.3
1When a laser is to be set on a
flat surface where the laser beam is
not centered in the pipe, use model
1230/1237 Heavy Duty Trivet
Plate and 1239 Universal Fixed
Pole.
2Using this system, the elevation
of the laser beam can be set by
either measuring down from a
grade offset hub outside the trench
or up from the floor of the manhole
to the beam.
3The 1239 Universal Fixed
Trivet has both cm/mm and
tenths/hundredths scales for setting
the beam elevation.
1230/1237 Heavy Duty
Invert Plate 5.4.4
The invert plates model 1230
(English) and 1237 (Metric) are
one piece cast aluminum support
plates that provides automatic self-
centering of the Laser in 250 mm
(10 in.), 300 mm (12 in.) or 400
mm (15 in.) pipe diameters. The
invert plates are used along with
the 1239 Universal Fixed Pole for
setups on the manhole bottom,
outside of the manhole or in pipes
larger than 400 mm (15 in.)
diameter.