Vivax Metrotech vLocDM, User Handbook Manual

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4.5 Selecting the Correct Frequency
The available frequency options are:
• 98Hz, 128Hz, 512Hz, 640Hz, 3Hz/98Hz, 3Hz/128Hz, 4Hz/98Hz
• 4Hz/128Hz
• ELF1-3Hz/6Hz/98Hz
• ELF2-3Hz/6Hz/128Hz
• ELF3-4Hz/8Hz/98Hz
• ELF4-4Hz/8Hz/128Hz
• 3Hz/6Hz/512Hz
• 3Hz/6Hz/640Hz
• 4Hz/8Hz/512Hz
• 4Hz/8Hz/640Hz
3Hz/6Hz/98Hz or 3Hz/6Hz/128Hz are the most commonly used frequencies. They provide the low frequency
3Hz component required for current mapping and a low frequency (98Hz or 128Hz depending on local mains
frequencies) used to pinpoint the position and is used to determine the pipe depth. The 6Hz enables the locator
to calculate the signal direction.
The other frequency options can be used to improve reception in areas of high interference.
4.6 Output Current Select
There are seven current settings:
• 100mA
• 300mA
• 600mA
• 1A
• 2A
• 3A
• 4A (When a single locate frequency is selected)
Choosing the correct setting for a particular application depends on many factors but as a general rule “the
higher the setting the better”. The higher the current the more stable the readings at long distance and larger
currents create larger current changes at faults. However, it will not always be possible or desirable to apply the
maximum current.
With the transmitter connected as above, select the 3A position. Wait to see if any alarms are displayed such
as over voltage, over power, over temperature. If after 20 seconds no alarms are shown, note the return current
reading. This should be 3A+/- 0.1A. Now note the output voltage. This should be less than 100V. The transmitter
stabilises the output current by altering the output voltage. The output voltage limit is 100V. If the current cannot
be stabilised with a voltage less than 100V it will display an overvoltage alarm. The transmitter is not damaged if
this is displayed but the output will not be stabilised. To overcome this, select a lower current setting.
4 Transmitter Functions and Operations
WARNING
Use a cable locator to ensure the area is clear of services before the rod is driven into
the ground.