Table 2-2. Power Transformer Output Voltages
Rated Voltage
Type
Pin No.
No-load AC Voltage [V]
AC [V]
DC [V]
220V
29.3
27.1
32.3
240V
9.0
8.33
+9.0/– 9.9
29.3
27.7
33.3
120V
8.96
8.41
+9.27/– 10.0
NOTE: Column “DC
for the rated voltages indicates the output of the transformer when the
board is connected. The plus and minus values between pins 10 and 9 are different due to the
voltage drop across thermal fuse TF2.
2.3.2 Regulator Circuit
output from the ROC filter unit are input to connector CN8 of the
board. The
regulator circuit can be divided mainly into two portions, the +24 V/+5 V and + 12 V lines. AC 1 is
full-wave rectified by diode bridge DB 1 and converted to +24 V and +5 V via the chopper type
switching regulator.
is half-wave rectified by D4-C 10, converted to + 12 V, and input to the optional
interface board.
,
&_
3.15A
●
●
13A)
,
I
3
O.in
1
Fig. 2-5. +24/+5 VDC Regulator and +12 V Half-Wave Rectifier Circuits
2-5
