DSP-13 User Manual
Page 11 of 16
DSP13_MAN_B
For existing driving surfaces of asphalt or concrete, a single 1/4” saw slot can be cut to the desired location of
the sensor with an appropriate cutting disk for the road surface. At the desired sensor location, a 1” to 2” hole
should be core drilled into the driving surface.
The sensor should never be installed into the saw slot. Doing so
will void the warranty for the sensor.
The saw slot should be deep enough that the sensor and lead-in cable
will have a minimum of ½” of sealant above them in the slot. More is better. Going too deep with the saw cut is
also a concern. Deep cuts in a road surface may impact the structural strength of the roadway, especially if any
reinforcement material is cut.
Once the saw slot has been cut, the slot should be cleaned of all loose material. High pressure air should be
directed in to the saw slot to remove all debris. This will also help remove dust from the saw cutting operation
from the sides of the saw slot. This will allow better adhesion of the sealant to the saw slot.
In order to keep the sensor cable at the bottom of the saw slot, 1” pieces of backer rod should be placed in the
saw slot every 1 to 2 feet. The backer rod should be sized such that it fits snugly in the saw slot. Use a blunt
object (not a screwdriver) to press the backer rod pieces down into the saw slot as far as they will go. Keeping
the sensor cable at the bottom of the saw slot allows the sealant to provide the maximum amount of protection
possible from foreign object penetration. Never use a continuous piece of backer rod over the sensor and cable,
as this would prevent the sealant from encapsulating the sensor and cable. NOTE: Backer rod is available at
most home improvement stores and in several sizes.
The sealant used should be appropriate for the roadway surface that was cut. Generally, epoxy, urethane, or
polyester based sealants are used for concrete surfaces and polyester or urethane based sealants are used for
asphalt surfaces. However these are not hard guidelines and specific circumstances will determine which type
of sealant should be used.
