Metalarm
™
Series 3500 Metal Detectors
25
CORRECTIVE MEASURES
• Use another power line, (without the varying
inductive loads) for the metal detector.
• Disconnect electrical equipment causing the large
inductive loads.
• Connect interfering electrical equipment to another
power source.
• Re-route the power line to the metal detector.
• Install a constant voltage transformer (120 VA
minimum) between metal detector and
power source.
PROXIMITY OF SEVERE RF RADIATION SOURCES
Electrical or electronic interference can be radiated
into the sensor coil or introduced into the metal
detector from other energy emitting devices such as
arcing motors, arc welders, and arcing relay points.
CORRECTIVE MEASURES
• Remove or replace equipment causing
the interference.
• Operate welding equipment only at times when
metal detector is not required to operate.
Call the factory service department if unable to arrive
at a satisfactory solution.
ELECTRONIC CIRCUIT BOARD REPLACEMENT
Normally, access to the electronics is not required but
if the circuit board requires replacement, the following
procedures must be used.
Turn off the main supply to the control unit and
disconnect all terminal blocks connected to the base
of circuit board by pulling downwards.
Undo the three panel attachment clips by turning them
1/4 turn counter-clockwise.
Undo the five screws holding the two mounting
brackets and remove.
Undo the five standoffs and three mounting screws.
Remove the circuit board and inspect the enclosure.
Remove any foreign material such as loose pieces of
metal filings or wire cutting etc.
Install the new circuit board in the reverse of the
above procedure. Refer to the section for testing
and operation.