1. Switch on the power and observe the lights on the front of the detector.
2. The top light is an indication of power. This light must always be on.
3. The middle light indicates if there is a vehicle present on the loop. When the power is first applied to the
detector this light flashes a couple of times indicating that the detector has tuned to the loop. The
number of flashes indicates the frequency of the oscillator multiplied by 10 KHz (Kilohertz). For example,
7 flashes indicates that the loop frequency is between 70 and 80 KHz. If this light does not flash and
stays on there is a problem with the loop or wiring.
4. The bottom light comes on if there is a problem with the loop. Some of the common problems are:
a. The loop wires have a short circuit. Check the wiring.
b. The loop inductance is too small. More turns must be added to the loop. For a 2m by 1m loop 3
turns is suitable. A wire size of 1.5mm
2
cross sectional area is recommended.
c. The loop inductance is too big. This is very seldom a problem as most loops have an
inductance of less than 500uH. A solution is to reduce the number of turns on the loop.
d. The loop is open circuit. Check the wiring.
If the fault light is on it is easy to identify that there is a fault with the loop or wiring and this can easily be
repaired. If the detector is erratic the problem may be more difficult to find. The first step is to check the loop
wiring. Many intermittent problems can be attributed to poor wiring connections and even movement in the loop.
The next step is to switch on the frequency switch to change the loop frequency, and finally it may be necessary
reduce the loop sensitivity by switching on switch 2 or 3.
Care must be given to the placement of the loop. The loop should not be put below reinforcing mesh, should be
kept away from any metal objects such as a manhole and should also not be too close to sliding gates, etc.
Contact Details
Powering up and testing the LD160
Refer to our web site for distributor details.
Email: [email protected]
Web: www.proconel.com
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