The first method is to connect the red lead of the transmitter to the station wire leading to
that valve and the black to ground as described above. Operate the Pro800 as above
and begin your locate. When you reach the point where a valve/solenoid is located, the
signal will expand into a large (approx. 2-4ft) diameter area of signal. This is your
indication that you are over a valve or solenoid.
The second method starts by tracing the wire path as previously described. Irrigation
valves are located in null mode only. Once the wire path has been traced you must
power the transmitter off, remove the black lead from the earth ground and connect it to
the common wire. In the case of multiple common wires it is suggested that you isolate
and connect to the common wire that services the target valve. Connecting to multiple
commons will work, however it weakens the signal response.
Power the transmitter on and adjust the output signal to suit your needs. High power
output is not necessary and will limit battery life. It is advised that you once again point
the receiver at the transmitter to assure that both units are on and functioning properly.
Slowly follow the pre-marked wire path. There will be an absence of signal response due
to cancelling of the parallel wires until you near the valve. As you move closer to the
valve the receiver will begin making a chattering sound which will intensify and distort,
turn the volume down and take your time.
Even with the volume at its lowest setting the response of the valve solenoid will be very
loud. Pinpointing the exact location of the solenoid is possible by decreasing the volume
and taking your time. The lower the volume is, the more accurate you can be.
Slowly start moving the receiver in an X pattern above the high pitched area, continue
reducing the volume while moving the tip of the receiver closer to the ground. Between
the proximity of the receiver tip to the ground and the reduction in volume you can tell
exactly where the valve solenoid is. Use a probe to find the outline of the valve box
before excavating. This will assure that unwanted damage isn't a result of your locate.
Once the valve is located, verify that it is indeed your target either manually, with the
Pro48, or from the controller.
There may be more than one valve on the cable being traced. You may wish to continue
past the first valve located to determine if other valves are also located on this wire.
Broadcast Mode
–
Broadcast mode is different from using the direct method of
connection that has previously been discussed. It is not as precise or strong as direct
connecting, but when access to cables is limited or just a quick scan is required,
Broadcast Mode can be very useful.
Broadcast mode is excellent for finding telephone or cable TV lines. It is less useful with
wires attached to solenoids. The principle in use with Broadcast mode is AC induction.
On ordinary wires, that works well. And it can work for sprinkler wire but the solenoid
has to be eliminated from the circuit. This can be done by disconnecting the solenoid
and grounding the wire manually. The problem is that the solenoid acts as a signal
dampener with AC inductance. By removing the solenoid from the circuit, you can find
sprinkler wires in broadcast mode. Deactivated 2-Wire systems do not have this issue
and are traceable as they exist in the ground.
