
DSP-19 User Manual
Page 19 of 24
DSP19_MAN_A
It is important that the Mini-Loop be installed in a vertical position and that the vertical position of the Mini-Loop
be maintained. Under some soil conditions, installation can be further simplified by installing the Mini-Loop inside
a length of PVC pipe (not steel pipe) with an interior diameter of about 1½ inch. In this case, the hole must be
slightly larger than the outside diameter of the PVC pipe, typically 2 inches. After insertion of the PVC pipe and
Mini-Loop, all cavities are back-filled with fine, dry sand and the installation completed in the normal manner.
Side Detection Zone Placement
When the roadway is less than 11 feet wide, it may be possible to place the Mini-Loop on the side of the roadway
and achieve acceptable detection performance. The Mini-Loop can be installed at a 45 degree angle so that the
top of the sensor points towards where the vehicle is to be detected. This can be very useful when applications
where there is already an existing driving surface that the customer does no want distrubed.
Figure 9: Mini-Loop Side Installation
When the roadway is greater than 11 feet wide, requiring a greater detection zone, you have two options. First
is to add a second Mini Loop to the opposing side of the roadway. The probes must be wired in series. However,
this configuration cuts the sensitivity of the Mini-Loop in half and does not allow for different sensitivites for the
two Mini-Loops.
The second is to use another DSP-19 with it
’
s own Mini-Loop installed on the opposite side of the roadway. In this
configuration both Mini-Loops have full sensitivity and their sensitivities are individually adjustable.