Eurotherm 590+ Series, Product Manual, Page: 279 / 308

Standard and Optional Equipment
13-5
590+ Series DC Digital Converter
AH385851U002, U003, U004, U005 (Frame 3)
(590+ - 4 Quad, 591+ - 2 Quad; Low and High Volt)
Power supplies for the controller are generated from the single phase auxiliary supply via a
switched mode power supply. The incoming supply is directly rectified to provide a high voltage
dc power rail. A high voltage transistor switches this rail on to the primary of a high frequency
transformer, the output of which is rectified and smoothed to provide the dc power supply rails.
The +5V dc rail is monitored via a reference element and a control signal returned via an opto-
isolator to the control element of the high voltage switching transistor. The
±
15V dc rails are
generated via separate secondary windings which are rectified, smoothed and stabilised by linear
regulators. The SMPS operates over an input voltage range of 110V to 240V ac
±
10%, 50/60Hz.
The auxiliary supply fuse FS1 provides protection of the high voltage elements.
F8
F16
G K
G K
F19
F18
D1 D2
D3 D4
+24V
0V
RFI
GND
F25
F23 F24
F21
FS1
F22
F27
D5 D6
D7 D8
TRANSFORMER
PTR
PTY
(F14)
(F13)
(F17)
(TH1) (TH4) (TH3) (TH6) (TH5) (TH2)
F15
F9
FS2
FS3
FS4
A- A+
EX A-
EX A+
PLN
PLM
PLL
PLK
PLJ
(F+) (F-)
A+
A-
L1 L2 L3
F26
F28
Figure 13-6 591 Power Board 2 Quad (AH385851U003, U004)