Cebora PLASMA SOUND PC 110/T Manual De Servicio página 41

CEBORA S.p.A.
After analysing this voltage reading, control board (48) also drives relays RL1 and RL2
located on IGBT board (31) to ensure the primary windings of power transformer (52)
are connected correctly based on the mains voltage present at the machine input.
At 208/220/230 Vac, both primary windings are connected in parallel (RL1=ON and
RL2=OFF), with voltage 400/440 Vac both primary windings are connected in series
(RL1=OFF and RL2=ON).
A stabilised direct voltage of approximately 13.8 V is sent from connector CN1 pin 4
to connector CN9 pin 4.
A non-stabilised direct voltage obtained from the secondary winding of transformer
TF2 at 24V is sent from connector CN4 pin 1 and pin 2 to connector J10 pin 1 and pin
2 of display board (57). This direct voltage is used to power the display board.
Wires carrying the three mains phases to the input of three-phase bridge rectifier
(41) are connected to points U1, V1 and W1 of service filter board (7).
Polyester capacitors C1, C2 and C3 present on IGBT board (31) are precharged on
service filter board (7) by means of positive temperature coefficient resistor PTC2 and
relay RL3. Positive temperature coefficient resistor PTC1 has been replaced with a
short-circuit for technical reasons.
Microcontroller IC4 can be programmed directly on the circuit by means of 4-way
connector CN5.
The input of stabilised power source (6) used to power the fan and part of display
board (57) is connected to the mains via connector CN2 pin 5 and pin 7. Connection to
the stabilised power source network (6) takes place by controlling relay RL5 present on
service filter board (7)
A voltage of 24 V +/- 15 % is present at terminals 1 (+) -2 (-) of connector CN4 while
the voltage is 45 V +/- 15 % under no load with connection to display board (57).
Filter board (5) 5602597
Filter board (5) is used to filter out any electrical noise potentially present at the
power source output.
Control board (48) 5602584
Control board (48) contains the power source main microprocessor and supervises
the management of the other boards. It regulates the cut-off current, generating a
PWM signal to be sent to IGBT modules (30) through isolated drive circuits built into
the board, and communicates with display board (57).
The board is powered by service filter board (7). A voltage of approximately 13.8 V
from service filter board (7) is present at connector CN9 pin 4 (positive) and CN9 pin 5
(negative). A stabilised voltage of 5 V used to power microcontroller U3 is obtained
from this 13.8 V voltage via regulator U7.
Amperometric transformer SH1 outputs mounted on IGBT board (31) are connected
to FASTON connectors FS3 and FS4 in control board (48).
Amperometric transformer SH1 reads the current flowing in the primary winding of
power transformer (52). The amperometric transformer output signal and the Hall effect
current sensor output signal are used together to control the power source output
current.
The output and power sources of Hall effect current sensor SH1 mounted on
secondary winding board (32) are connected in control board (48).
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10/07/2019