This document provides a precise method for locating electrical leaks in a wireline using a digital ohmmeter. The method involves setting up equipment between a pay off drum and take up drum, connecting a power source and meter, then slowly spooling the cable while monitoring the meter reading to pinpoint the location of the leak. Key steps are connecting the leaking conductor to a collector, connecting the meter and power source appropriately, and watching for a change in the meter reading to identify when the leak passes under the test lead hook.
This document provides a precise method for locating electrical leaks in a wireline using a digital ohmmeter. The method involves setting up equipment between a pay off drum and take up drum, connecting a power source and meter, then slowly spooling the cable while monitoring the meter reading to pinpoint the location of the leak. Key steps are connecting the leaking conductor to a collector, connecting the meter and power source appropriately, and watching for a change in the meter reading to identify when the leak passes under the test lead hook.
This document provides a precise method for locating electrical leaks in a wireline using a digital ohmmeter. The method involves setting up equipment between a pay off drum and take up drum, connecting a power source and meter, then slowly spooling the cable while monitoring the meter reading to pinpoint the location of the leak. Key steps are connecting the leaking conductor to a collector, connecting the meter and power source appropriately, and watching for a change in the meter reading to identify when the leak passes under the test lead hook.
This document provides a precise method for locating electrical leaks in a wireline using a digital ohmmeter. The method involves setting up equipment between a pay off drum and take up drum, connecting a power source and meter, then slowly spooling the cable while monitoring the meter reading to pinpoint the location of the leak. Key steps are connecting the leaking conductor to a collector, connecting the meter and power source appropriately, and watching for a change in the meter reading to identify when the leak passes under the test lead hook.
The most common method of locating electrical leaks in a wire- • Turn the meter on, set it at the lowest dc voltage range, line is to “burn out” the leak until the conductor is 200 mv. shorted to the armor and then use a digital ohmmeter to • Connect the Meter NEGATIVE, long test lead to the determine an approximate location of the leak. This is a collector, mounted on the TRUCK DRUM. quick and easy method of finding a leak; but, there is a disadvantage. When burning out the leak, it can melt the • The test lead with the copper hook is connected to the copper, plastic and sometimes burns the inner armor wires. If Meter POSITIVE, and the copper hook is hung on the cable this occurs it can be impossible to determine the cause of the between the pay off and take up. original leak. • Connect the POSITIVE lead of the POWER SOURCE to the frame of TRUCK DRUM. If it is important to determine exactly what caused the leak or • Connect the NEGATIVE lead of the POWER SOURCE to the technical bulletin
if the high voltage equipment is not available to burn out the
leak, then a alternate leak locating procedure is required. This frame of SHOP DRUM. procedure will locate leaks that are as high as 10 Meg-Ohms • DO NOT CONNECT THE POWER SOURCE DIRECTLY TO THE and locate the leaks within +/-1 inch. To use this method, the CABLE ARMOR, ONLY TO THE FRAME. The power source following shop conditions must exist: can arc when connected and burn an armor wire. • The shop is setup to reel the cable from a metal pay off or truck drum to a metal take up shop drum. Leak Location • The pay off frame is electrically insulated from the take up • With all of the connections made in accordance to the stand. SETUP PROCEDURE listed above, place the copper hook • A POWER SOURCE, such as a 6 or 12 volt car battery or from the meter positive in contact with the cable armor. a battery charger is available, with leads long enough to • The meter will indicate a positive voltage if the leak is on connect the power between the pay off and take up stands. the SHOP DRUM. • A collector is mounted on the pay off, truck, drum and is • The meter will indicate a negative voltage if the leak is on called TRUCK DRUM. the TRUCK DRUM. • A DC voltmeter that will indicate plus and minus voltages • The cable is then spooled in a direction to move the leak off and has 200mv sensitivity and 10 Meg Ohms input of the drum it is located on. impedance is required. • The copper hook, connected to the meter positive terminal, • A set of well insulated test leads to reach between the is held in contact with the cable armor as it is being meter, the collector on TRUCK DRUM and one test lead, spooled. fixed with a copper hook, to reach the cable. • When the leak comes off the drum, the meter voltage reading will start to decrease. • When the meter reads zero, the leak is located directly under the copper hook location. • If the meter voltage changes polarity, you have passed the leak. Connection Summary • TRUCK DRUM has the collector • Connect leaking conductor to the collector • Connect NEGATIVE METER lead to the Collector TRUCK • Connect the test lead with the copper hook to the METER POSITIVE • Connect POSITIVE power source to frame of TRUCK DRUM. 1. If the meter indicates a POSITIVE voltage, the leak is towards the SHOP DRUM. • Connect NEGATIVE power source to frame of SHOP DRUM 2. If the meter indicates a NEGATIVE voltage, the leak is towards the TRUCK DRUM. Miscellaneous • Be sure the plastic insulation is CLEAN on both ends. Setup Procedure • String the cable between the pay off, truck, and shop • The pay off and take up stands must not be connected drums. Going around a sheave wheel is ok as long as this mechanically. sheave wheel is electrically insulated from both pay off and • Do not connect the power source leads directly to the cable take up drums. armor. This connection can spark when connected, burning • Connect the leaking conductor to the collector on TRUCK cable armor. DRUM. • Be sure the insulation on the conductor is clean. • The other end of the leaking conductor, on the SHOP DRUM, must be free and clean.