Technical data • Fully assembled device
30
Automation PC 810 with GM45 CPU board user's manual V1.28
2.3 Power management
2.3.1 Supply voltage block diagram
The following block diagram illustrates the simplified structure of the APC810 supply voltage for system units.
24 V
15 V
Supply voltage
+24 VDC
Capacitors
(for min. 10 ms)
3V3 standby
3V3
3V3
5 V
15 V
+12 V
+12 V
5 V
5 V
15 V
Power button on
15 V
-12 V
-12 V
5 V standby
electrically
isolated
UPS battery
UPS add-on
module (optional)
+12 V
PCI bus
Figure 4: Supply voltage for system units
Description
15 V is generated from the supply voltage using a DC-to-DC converter. This electrically isolated 15 V supplies
further DC/DC converters, which generate the remaining voltage.
After the system is turned on (e.g. using the power button), the 3V3 and 5 V voltages are applied to the bus. At
the 5 V output, another DC-to-DC converter generates -12 V and applies this to the bus. An additional DC/DC
converter gen12 V.
The optional Add-on UPS (with battery unit) is supplied with 15 V and provides an uninterrupted power supply from
the 15 V bus during power failures.