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Using Current Indications During Locating Both the Transmitter and Receiver will indicate cable current. These current indications will help to select a trace frequency, identify the correct cable and trouble shoot the set up. When using the direct connect method, the Transmitter output current number is displayed. A "LO" display, or number less than 50, indicates a weak tracing signal. A number higher than 70 represents a strong tracing signal. When the Receiver is used to find the cable near the Transmitter connection point, the current number displayed in the Receiver should correspond (within 5 points) to the Transmitter number: IF you are over the correct cable, AND most of the signal is flowing in that cable. Note: On the Transmitter every ten units on the current display represents a factor of two in current magnitude. On the Receiver, trace current readings for the additional auxiliary frequencies (except LF) are displayed in milliamps. For all other trace frequencies every ten units on the Current display represents a factor of two in current magnitude. When the Transmitter signal is applied using the Dyna-Coupler, the Transmitter current display indicates the current in the coupler and not in the cable. In order to get a measure of the cable current, point the Receiver at the exposed cable about one meter from the Dyna-Coupler. This will be the current number that should be used to identify the correct cable. Page 13 In general, when the Transmitter is set up to apply more current on the target cable than any other cable, the cable can easily be identified because the Receiver current reading will be highest. Note: Since some of the signal in the cable will bleed into the earth, it is expected that the Receiver current indication along the cable will decrease gradually away from the Transmitter. This effect is more pronounced at higher frequencies. LOCATING SHEATH FAULTS (2273E ONLY) Transmitter Setup Remove both the near-end and far-end shield bonds from the test section. Perform a battery test then with the Transmitter off, connect the Black clip to the ground rod. Place the ground rod behind the Transmitter, away from the faulted section, and in line with the cable path. If necessary, extend the ground lead with the Ground Extension Cable. Attach the Red clip to shield. Press to turn the Transmitter on in the Ohms mode . Measure the fault resistance. The results are displayed in ohms. Note that failure to disconnect the shield bonds at either the near- end or the far-end produces a heavy fault indication. Press again, to select the Fault mode . For maximum fault sensitivity, select high output level by pressing . Receiver Setup Press to turn the Receiver on. Press to select Fault mode . Connect the Earth Contact Frame to the accessory jack on the Receiver using the earth frame cable. Near the location of the ground rod (about one step away), insert the frame probes fully into the ground with the green-banded leg towards the fault and in line with the cable path. Press to record a fault level reference visible in the lower left corner of display. Page 14 The Receiver bar graph is visible on the right side (green). This indicates that the fault is ahead of the operator in the direction of the green-banded leg. Continue along the cable path, reinserting the frame probes every few steps while watching the Receiver bar graph. When the bar graph is visible on the left side (red), the fault has been passed and is now behind the operator. Move back, inserting the frame every few inches, until the bar graph returns to the green side. Turn the frame ninety degrees to the cable path. The fault is located beneath the center of the frame when the bar graph changes from one side to the other. To verify the fault location, insert the frame’s red leg directly on the spot identified above. Pivot the frame in a circle around red leg re-inserting the green leg in ground every few degrees of the circle. The bar graph should always be on the left (red) indicating that the fault is directly below red leg. cable path Red leg After a fault is found and pinpointed, move the Earth Contact Frame about one frame width away from the fault and insert it into the ground with the green-banded leg towards the fault. Compare the numeric indicator reading with the fault level reference in the lower left corner of the display. If they are close, the fault is the major one. If the fault reading is 20 points less than the reference reading, multiple faults may exist. Further searching is necessary to find the fault with the highest reading. Page 15 LOCATING AN ACTIVE DUCT PROBE (ADP) Press to turn the Receiver on. Press to select the 33 kHz frequency. Press to select the Peak mode . If you find that the received signal is too weak in this mode, try the Special Peak mode. To select Special Peak mode: from Peak mode, press and hold , then press to toggle between Peak and Special Peak modes. While in Special Peak mode, the Peak flag w...

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