Panasonic JB-3300 Technical Manual page 340

Rectifying/Smoothing Circuit
D41
Mg
VT
R45
R44 |
¢-W\-4
C44] '
+—| |-+ RF40 —_—
TH40
4 ~ csogyt
R43 r ?—
ARI
SW |
—~Oo-
csim
L__o"p
Figure 4-2 Rectifying/Smoothing Circuit
The current is rectified by diode RF40 and smoothed by capacitors C50 and
C51.
By changing the mode of rectification with SW1, the voltages provided to
the smoothing capacitors C50 and C51 are equalized for both 115 V and
230 V inputs. That is, full wave voltage doubler rectification is
effected for 115 V input and full wave rectification for 230 V input.
When 230 V is applied at the 115 V setting, the arrester AR1 is discharged
and melts the fuse Fl, protecting the converter circuits. To restore this
unit to normal set the input voltage and replace fuse Fl. The arrester
AR1 is separated from the circuit by the 1 circuit of the selector switch
SW1 when the input is set for 115 V.
TH40, F3, and R43 comprise an inrush current restriction circuit. In this
circuit, R43 restricts the volume of the charging current flowing through
C50 and C51 when the input voltage is applied. C44, R44, R46, and D4l
supply the gate signal to trigger TRIAC TH40 during operation.