2. Design and method of operation
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2
Design and method of operation
2.1 Functional principle
Rece
iver
Trans
mitte
r
Rece
iver
Detection coil
Signal amplifier
Analog/digital
converter
LCD graphic
display
Memory for
10 products
CU electronics
IO electronics
Power
supply
CPU
Relay
I/O interface
Oscillator
Control Unit
Control panel
Logbook
real time clock
CPU
Monitoring
The metal detector works with the so-called "balanced coil" principle:
The transmitter winding in the search coil creates a high-frequency electromagnetic field, which is re-
ceived by symmetrical placed receiver windings. The windings are connected against each other;
when undisturbed, the system is in balance.
An electrically conductible object within the detection area disrupts this balance and the electronic cre-
ates a switch signal.
A "teach in process” allows to suppress the conductivity of the product itself. Deviations from the
taught-in product are usually caused by metal contaminants, which are detected by the device with
high precision.
The metal detector is equipped with comprehensive test and analysis software to ensure fault-free op-
eration and retracing of product errors.
For reasons of the employed technology it is not possible to guarantee 100% metal
detection.