Heath Consultants Sure-Lock Utility Pro - Manual (Page 33)

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These results may also indicate that the operator should reposition the transmit-
ter or go to a different transmitter mode of operation to energize the conductor.
Factors Affecting Depth Readings
1. Interfering conductors in the area.
2. Type and conductivity of soil.
3. Receiver not centered on target.
4. Depth of burial versus size of target.
5.
depth readings.
6. Changing conductor depth or a tilted conductor at the reading location.
7. Frequency selection (lower frequencies preferred).
8. Grounding method.
The above factors should always be taken into consideration when taking a
calculated depth reading with the receiver. If not, calculated depth may have
inaccuracies greater than 20% of the actual value.
**NOTE**
THIS CONDITION MAY BE EVALUATED USING TWO METHODS. ONE
METHOD IS BY PIVOTING THE RECEIVER 180 DEGREES WHICH MAY
PRODUCE DEPTH READING WHICH DIFFER BY 10%. SUCH DIFFER-
ENCES UP TO 15-20% MAY BE AVERAGED AND WHICH CAN BE THE
RESULT OF A TILTED CONDUCTOR WHICH OCCURS NATURALLY
WHERE A FORWARD OR RE- VERSE GRADE EXISTS. DIFFERENCES
GREATER THAN 20% INDICATE INACCURATE DEPTH READINGS. A
SECOND METHOD IS SOMETIMES CALLED THE “LIFT TEST” AND IN-
VOLVES TAKING A STANDARD CALCULATED DEPTH READ- ING AND
THEN LIFTING THE RECEIVER UP A KNOWN DIS- TANCE AND OB-
SERVING THE NEW CALCULATED DEPTH READING ON THE DISPLAY.
THE UPDATED CALCULATED DEPTH READING SHOULD INCREASE
BY THE DISTANCE THAT THE RECEIVER WAS RAISED. PIVOTING
THE RECEIVER MAY ALSO BE USED WITH THE LIFT TEST.