Humboldt H-3220A Benkelman Beam - Manual (Page 5)

Calculations
The H-3220A series Benkelman Beam has a level ratio of 2:1, the H-3221HA
Digital indicator has been calibrated to read the true deflection of the beam
probe point, eliminating the need for any conversions. (For those using dial
indicators: Pavement Reading = Maximum Reading minus Final Reading.)
Indicator Models Available
H-3221HA— Horizontal, Digital Indicator, 1-inch range, .001 accuracy
H-3222— Vertical Dial Indicator, 1/2" range x 0.002" divisions
(travel is 1" on dial)
H-3222M— Vertical Dial Indicator, 14 mm range x 0.02 mm divisions
(travel is 28mm on dial)
Specifications
Main Body: 55" (1397 mm) long, black aluminum finish
Probe Beam: Aluminum, 8ft. (2.4 m) long, telescopes into case for storage
Probe Fulcrum: Ball pivot bearing, gives lever ratio of 2:1
Vibrator System: Operating switch mounted on top of instrument section
(requires 4 “D” –size batteries, supplied)
Indicators: (not included)
Leveling Wheel: Adjust beams to proper elevation
Open Length:
12ft. (3.7 m) long
Weight: Net 35lbs. (15.9kg)