DSP-13 User Manual
Page 15 of 16
DSP13_MAN_B
Power LED Shows Quick Flashes Once Every Two Seconds
This flash rate indicates that the detector has had a failure, but is currently working correctly. There are three
types of failures that the detector will remember:
Flashes Remembered Failure
Corrective Action
1
DSP13M Failure
Replace DSP13M if issue persists
2
DSP13S Failure
Replace DSP13S if issue persists
3
Communications failure
See text below
Intermittent communications failures are usually wiring connections. Any splices in the lead-in cable should be
redone. If there are any wire nuts used in the circuit, remove them and replace with a crimp connection or
preferably, a soldered connection. The fault could also be a fatigued point in the cable. This can occur at
locations where the cable crosses an expansion joint in the road surface. Any place where the cable must move,
even if only a very tiny amount, can cause wire fatigue. The actual failure point may be very difficult to find.
Often the sensor must just be replaced if the issue persists but cannot be found.
Other possible source of fault is a foreign object being embedded in the saw cut and damaging the cable or
sensor. Another is that the cable has been damaged where it enters or exits a conduit or junction box, or that a
conduit that the cable is in has been damaged (crushed, kinked, bent, cut, etc.).
Detect LED Intermittently Comes On / Stays On Without a Vehicle Present
This type of symptom is usually caused by one of two issues: electrical interference or moving objects in
proximity to the sensor.
Electrical Interference
– There are several possible sources of electrical interference: power lines and electric
motors, just to name a few.
Anything that uses electricity is a possible source for electrical interference depending on its proximity to the
sensor and the amount of energy being used. If you believe the sensor is experiencing electrical interference,
turn off the device believed to be the source of the interference and see if the problem goes away. Sometimes
this is not possible and more technical means are needed to help identify the source. Call Technical Support in
this case.
Moving Objects in Proximity to the Loop
– Objects that can move and are ferrous, metallic, or somehow
electrically conductive, may cause detection issues.
A common issue is movement of a slide gate or gate arm in close proximity to a sensor. The best solution would
be to move the detection area further away from the moving gate. We recommend that all sensors should be at
least 6 feet from a slide gate. Try lowering the sensitivity one level at a time so that the desired vehicles are still
detected, but not the moving gate. NOTE: Do not lower the sensitivity too much or vehicles will no longer be
detected.
Another possibility is metal objects in close proximity to the loop. Utility manhole covers are objects that may
move slightly when vehicle tires drive over them, especially if the vehicle turns while a tire in on the cover. Most
