Spectra Precision GL422N, Полезные советы и рекомендации

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HOW TO SET SLOPES (FALLS/GRADES)
Working Example 2 (when you do NOT know the % grade to set)
Models LL100N & LL300N:
To make the next adjustment, use the RC601UK infra-red remote control if distance “ D ” is less
than 20m. If “ D ” is more than 20m, a colleague must assist you using the remote control, being
within 20m of the laser level.
Hold the UP arrow button on the remote control to move the laser beam down the measuring
staff until a continuous tone is heard. The laser is now set at the desired Fall.
Model HV101:
To make the next adjustment, use the RC601UK infra-red remote control if distance “ D ” is less
than 20m; or a colleague at the laser, if “ D ” is more than 20m.
Hold the UP arrow button to move the laser beam down the measuring staff until a continuous
tone is heard. The laser is now set at the desired Fall.
Models LL300S, HV302, HV302G & GL422N:
To make the next adjustment, use the RC402N radio remote control if distance “ D ” is less than
100m; or a colleague at the laser, if “ D ” is more than 100m.
Hold the UP arrow button to move the laser beam down the measuring staff until a continuous
tone is heard. The laser is now set at the desired Fall.
Important note: If the laser is switched off and on again, this value is lost; as the laser reverts
back to auto level.
Keep the detector clamped in place on the measuring staff & by moving between covers A & B ,
keeping a continuous tone on the detector, the ground can be cut away at the base of the staff ,
following the grade set by the laser level.
Obviously, allowance must be made for the actual depth of the pipes’ exit & entry positions in
each manhole.
Grade Ratio:
As an example, if distance “ D ” is 30m (30,000mm) & fall “ F ” is 375mm, the formula shown below
determines the Grade ratio:
Distance “ D ” in mm / Fall “ F ” in mm = Grade ratio.
i.e. 30,000/375 = 80
A 1:80 Grade (fall) is used typically for a foul drain run.