Keysight U2722A/U2723A User’s Guide 5Safety SymbolsThe following symbols on the instrument and in the documentation indicateprecautions that must be taken to maintain safe operation of the instrument.Direct current (DC)Equipment protected throughout bydouble insulation or reinforcedinsulationAlternating current (AC) Off (supply)Both direct and alternating current On (supply)Three-phase alternating current Caution, risk of electric shockEarth (ground) terminalCaution, risk of danger (refer to thismanual for specific Warning or Cautioninformation)Protective conductor terminal Caution, hot surfaceFrame or chassis terminal Out position of a bi-stable push controlEquipotentiality In position of a bi-stable push control
