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78-9000-5020-0 Rev C
The Path Marker option is used to locate a path marker, such as 3M™ Electronic
Marking System (EMS) Caution Tape of choice (TEL, GAS, WTR and W/W). This mode
has three search methods -Peak, Null and a combined Peak/Null response.-which can be
selected in the locate screen through [SK3].
Peak Mode
-
On Mode entry, the Peak Mode will give thestrongest audio and bar
graph response when the receiver is above the path marker.
Null Mode
-
On Mode entry, the Null Mode will give the strongest audio and
bar graph response when the receiver is to the front or back of the marker. Moving the
receiver directly over the path marker will produce a quiet response.
Peak/Null Combination
-
On Mode entry, the combined Peak and Null Modes
will respond with the Peak and the Null audio and bar graph response to allow for a
larger pattern of signal over the marker.
• The bar graph will increase, the audio will increase, and the signal strength will be
maximum when the locator detects a marker of the specified utility.
Single Antenna:
Use this antenna arrangement for all normal locates. If there seems to
be high noise then try the Dual Antenna to help filter out ambient noise.
Dual Antenna:
This mode can help locate when ambient noise is 25 or higher on the
signal strength display [10].
I. Sweeping and Locating the Tape/Pipe
Step 1. Make wide locate sweeps across suspected pipe direction inside the suspected
pipe corridor, every 2.5 ft (75 cm) until you detect the first marker.
Step 2.
When the first marker is detected, the pipe/tape direction can be determined by
rotating the locator and finding the direction of the highest signal strength.
Step 3.
Walk straight in the direction of the handle, making smaller left/right sweeps to
follow the path.
Step 4. Press depth directly over a marker with maximized orientation, for the
estimated depth to the tape.