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Block 26
Fan
Consisting of: V1.
Powered directly by block 13 (power supply) and cools the
power components.
Block 18
Block 19
Block 20
Block 21
Block 22
Block 23
Block 24
Block 25
Current potentiometer
Maximum current adjustment
Power transformer thermostat
Galvanic separator
Overvoltage safeguard
Undervoltage safeguard
Power supply identification 115/230V
Power supply LED
Consisting of: R52.
This is used to set the reference voltage needed to adjust the
output current: when the potentiometer knob is turned the
cursor voltage varies, thus varying the current from the
minimum to the maximum value.
Consisting of: R56, R57, R58.
Used to adjust the maximum cutting current to be supplied by
the power source.
Consisting of: ST1.
When the temperature of the power transformer is too high,
the thermostat transmit the information to block 21 (galvanic
separation). It is reset automatically after the alarm condition
has ceased.
Consisting of: ISO1.
Consisting of: R71, R73 and part of the control section.
If the main supply voltage exceeds the maximum value this
safeguard triggers (a tolerance of approx. ±15% of the power
supply voltage is allowed: outside this range the safeguard
triggers).
Consisting of: R72, R70 and part of control board.
If the main supply voltage falls below the minimum allowed
value this safeguard triggers (a tolerance of approx. ±15% of
the power supply voltage is allowed: outside this range the
safeguard triggers).
Consisting of: U1A, Q2, Q1 (voltage change board).
This is only present on machines with the automatic
identification function.
Identifies the power supply voltage level (115V or 230V) and
compares the values with a reference signal. The comparison
causes enabling of block 5 (filter) for operation in standard
mode (230V) or as voltage duplicator (115V). This block also
adjusts for the correct maximum current in relation to the
different operating modes.
Consisting of: D12 (D13 for Tecnica 152).
Indicates when the power source is correctly powered and
ready for use.
On machines operating exclusively at 230V
it is green. On
machines with automatic voltage identification (Tecnica 152) it
is green for operation at 230V and orange for operation at
115V
.
The signal arriving from blocks 20 and 21 (power transformer
thermostat and secondary diodes) is separated galvanically
and sent to block 16 (alarms) for detection of a possible alarm
event.
TECNICA 150-152-170-168GE
