Limiting Factors on Metal Detector Performance
(Article published by Nexus Metal Detectors)
How does a metal detector work
Metal detectors work on the principle of electromagnetic induction. The detector generates a magnetic field. When the search coil is in proximity of a conductive metal, the electromagnetic field transmitted by the detector creates Eddy currents in the metal. The Eddy currents create a secondary electromagnetic field around the metal target. This secondary field is detected by the metal detector in various ways depending on the specific technology applied..
How Ground Affects a metal detector
Mineralization
Nexus contains a technology which eliminates the effect of ground mineralization.
Detectors without this technology may have difficulty working in mineralized soil which contains various conductive minerals, such as magnetite, iron and salt. These minerals can cause interference with the electromagnetic field which the metal detector generates, this can cause false signals or mask smaller metal objects, and reduce depth penetration for all targets.
Electrical Conductivity
Soil can have different levels of electrical conductivity. Wet or salty ground are two examples of highly conductive soil. These conditions can cause the metal detector's electromagnetic field to dissipate faster which causes the range and sensitivity to reduce faster.
Interference
Nexus detectors have been designed not to be affected by power lines, even next to a power station the user can operate undisturbed. Other brands could have difficulty coping. If you hear interference there may be a different and very strong source somewhere nearby.
Ground Conditions
These conditions include mineralization as well as soil conductivity. Open holes under the ground and soil displacement caused by large rocks could also result in false signals.
The ground balance feature can assist in compensating the effects of mineralization and soil conductivity. Adjusting the detector’s Mineral Control to the ground enables ignoring of soil signals, allowing the focus to be on metal targets.
Moisture
Moisture percentage in the soil, especially when very high or interchangeable in an area, can affect the depth as well as sensitivity to smaller and deeper targets. Dry, compact soil could result in detecting targets deeper by our MP series metal detectors.. Wet, loose soil may limit depth, yet give higher sensitivity to shallow targets.
Metal detectors may be affected by the above factors, however, taking these under consideration and mastering the fine tuning of the adjustment functions a metal detector is equipped with, allows for peak search efficiency.
