Siemens SIMATIC IPC847D Operating Instructions Manual page 18

Overview
1.2 Design of the device
Operator control element
18
Item Description
③
On/Off switch (redundant power supply)
Used to connect the device to the mains.
Depending on the "After G3 On" BIOS setting,
the PC may turn on automatically. Otherwise,
you may have to operate the on/off button
on the front.
④
Acknowledgment button (redundant power
supply)
The acoustic error signal is deactivated when
the button is pressed.
Operating Instructions, 01/2014, A5E32997454-AA
①
SIMATIC IPC847D