Waters SYNAPT G2 Operator's, Overview And Maintenance Manual page 38

Main power switches
Switch
Pump override
EPC reset
Auxiliary
EPC
Vacuum
Electronics
1-20 System Overview
Description
Used during servicing, this control must remain in
the Auto position at all other times.
Used to reboot the embedded PC (EPC).
The electronics and EPC switches
Requirement:
must be switched on.
This switch provides for future needs by operating a
spare power source.
This switch controls the power supply to the
embedded PC.
This switch controls the power supply to the vacuum
pumps and system vents.
This switch controls the power supply to the main
control electronics, embedded PC, and auxiliary
components.