Using The Accessories; Using The Lpc Separation Filter; Using The A-Frame In Fault Finding - Vivax vLoc-9800 User Handbook Manual

8 Using the vLoc-9800
8.4

Using the Accessories

8.4.1

Using the LPC Separation Filter

The LPC separation filter (LPC) is used to safely inject a trace tone to a live cable via a domestic mains
socket, so that the cable can be traced from the premises to the connection in the street. It is suitable for
connecting to voltages between 100V AC and 250V AC.
Method:
Plug the LPC into the output socket of the transmitter. Identify a suitable main socket. If a switch is fitted to
the socket, switch off. Plug in the LPC to the mains socket and then switch back on. Set the LPC rotary
switch to match the two indicator lights. Set the transmitter to the frequency to be located.(8 kHz or 32 kHz
are good frequencies for this application). Set the output to mid range.
8.4.2

Using the A-frame in Fault Finding

The A-frame accessory is used to detect ground faults on pipes and cables. In the case of pipes, the faults
consist of coating defects. In the case of cables, faults are usually caused by insulation damage allowing the
metallic sheath (or internal conductor) to become in contact with the ground.
To detect a damaged section, the line should be isolated and have all ground bonding removed. This will
ensure that the ground fault is not masked by deliberate bonding to ground. The A-frame cannot distinguish
between these two situations.
After isolating the line, use the vLoc-9800 transmitter resistance measuring function, or a dedicated
resistance measuring device to confirm that there is a fault to ground. The A-frame will typically detect faults
up to 2 mega ohm and above (depending on the distance from transmitter, soil conditions etc).
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