Vivax Metrotech VM-880 User Manual

Controls and Indicators
1
2
3
4
1 Power signal warning. Could be a live cable.
2 Battery level indicator (Flashes when replacement is required)
Indicates polarity of field (+ or - )
3
Decrease sensitivity
4
Speaker volume setting
5
Numeric signal level indicator
6
Bar graph indicating signal strength
7
Sensitivity setting indicator
8
Press to switch on, then short press to change speaker
9
volume. Long press to switch off.
Increases sensitivity.
10
Short press auto sensitivity set. Sets sensitivity to 60% meter
11 deflection
Long press to invert screen when pinpointing
Checkout Procedure
1. Hold the unit in a vertical position well away from any
metallic objects. Switch on the unit and check that the
battery is good by looking at the battery icon. Replace the
battery if necessary. (See Battery Replacement section below)
2. Now momentarily press the auto sensitivity pushbutton.
The sensitivity setting indicator should show maximum. (if
not, find another test site) The display should read less
than one half and the numeric value should be less than 50.
3. Now lower the VM-880 down towards the PK nail.Stop
when the numeric valie increases by approximately 10 and
the speaker pitch increases.The distance from the nail
should be greater than 2" (50mm). This will vary greatly
due to site condition and PK nail tolerance.
4. If the unit fails this test, it should be returned to the factory
or approved service centre as there are no field serviceable
parts.
5
6
7
8
9
10
Operation
11
The VM-880 Ferrous Metal Detector locates only those ferrous
metals that attract the earth's magnetic fields, such as iron,
nickel, cobalt and their alloys, as well as magnets, such as
magnetic markers.
Utility objects that contain these metals would include PK nails,
marker stakes, valve boxes, cast iron pipe, manhole covers and
large iron tanks. It also locates objects that generate their own
magnetic field, such as magnets. This discriminating feature of
the VM-880 simplifies the operator' s search for a specific
magnetic target. The size, shape, depth and orientation of the
target object will define the "profile" or "signature" indicated on
the VM-880 meter.
To Operate the VM-880:
1. To turn on the unit, press the ON/OFF/Speaker pushbutton.
2. The sensitivity of the instrument will automatically set itself
to the last setting.
2
Greater than 2" (50mm)
3
3. There will also be a "+" or "-" icon on the screen. This indicates
the polarity of the magnetic field which will be explained later.
4. Sweep the area holding the unit such that it is pointing towards
the ground at an angle of about 45 degrees. Walk forward
slowly sweeping left to right and keeping the tip an even and
close distance from the ground.
5. When a ferrous object is approached the bar graph will expand
and the pitch from the speaker will increase. (Set the speaker
volume with a momentary press of the ON/OFF pushbutton)
6. Hold the unit exactly vertical to pinpoint the highest pitch and
largest bar graph deflection. If preferred, invert the screen by a
prolonged press of the auto sensitivity pushbutton. The numeric
value can be used to aid the pinpointing process. Refer to
below picture. Pinpoint in two directions to ensure the exact
location is found.
7. If the signal over ranges, use the
"+ " and " - " keys to bring the signal
back into the range of the bar
graph.
8. Alternatively pressing the auto
sensitivity pushbutton will alter the
gain automatically so that the bar
graph is set to approximately 50%.
"Signatures" of Different Targets
The following figures illustrate typical VM-880 responses to
common targets. With a little experimentation you will become
familiar with the "profile" or "signature" of each object you are
trying to locate.
4