Keysight Technologies U1732C Digital-Multimeter, DMM, U1732C 数据表

The following symbols on the instrument and in the documentation 
indicate precautions which must be taken to maintain safe operation of 
the instrument.

Direct current (DC)

Off (supply)

Alternating current (AC)

On (supply)

Both direct and alternating current

Caution, risk of electric shock

Three-phase alternating current

Caution, risk of danger (refer to this manual 
for specific Warning or Caution information)

Earth (ground) terminal

Caution, hot surface

Protective conductor terminal

Out position of a bi-stable push control

Frame or chassis terminal

In position of a bi-stable push control

Equipotentiality

Equipment protected throughout by
double insulation or reinforced
insulation