Jamar TRAX Apollyon Plus II, User Manual

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3-3
Step 2 - Select Layout
Once you have selected your location, the next step is to decide what lay-
out to use. Which layout you select largely depends on the type of data you
want to collect.
The L1, L2, L3 and L4 layouts allow you to record data for volume infor-
mation, while the L5 and L6 layouts allow you to record data for speed,
class and gap in addition to volume. Chapter 4,
Road Tube Layouts , con-
tains more detailed information on each individual layout.
Step 3 - Prepare the Road Tube Lengths
Proper tube length is a crucial aspect of accurate data collection. The fol-
lowing guidelines should be followed for all studies regardless of simplicity.
The lengths listed for each study below have shown to provide the best
results based on extensive testing.
L1, L3, L4, L5, L6 (Long tube setups)
To encompass all types of vehicles and speeds, a tube length of 40 to
60 feet for mini tube. These lengths should satisfy all requirements for
normal street, road, highway and interstate traffic patterns.
L2 (Short tube, long tube)
To ensure the pulses from the road tubes arrive at the counter in the
proper order, the tube length must be the same from the edge of the road
to the TRAX Apollyon Plus II. This will ensure that the pulse from the
short tube arrives before the pulse from the long tube.
To accommodate the required length of tube, tube splices may be used
to fit two tubes together. The splices are approximately three (3) inches
long, hollow and do not restrict the flow of air. Do not use the splices on
the roadway itself, only on the section of tube after the clamp nearest the
TRAX Apollyon Plus II.
Chapter 3 — Road Tube Installation