RIGOL DG1000Z Series - Manual (Page 198)

RIGOL Chapter 2 Command System
2-186 DG1000Z Programming Guide
[:SOURce[]]:VOLTage:UNIT
Syntax [:SOURce[]]:VOLTage:UNIT {VPP|VRMS|DBM}
[:SOURce[]]:VOLTage:UNIT?
Description Set the amplitude unit of the specified channel to Vpp (VPP), Vrms (VRMS) or dBm
(DBM).
Query the amplitude unit of the specified channel.
Parameter Name Type Range Default
[] Discrete 1|2 1
{VPP|VRMS|DBM} Discrete VPP|VRMS|DBM VPP
Explanation  When [:SOURce[]] or [] is omitted, the system sets the related
parameters of CH1 by default.
 Vpp is the unit of the peak-peak value of the signal; Vrms the unit of the effective
value of the signal; dBm is the unit of the absolute value of the power of the
signal. The relation between Vpp and Vrms differs for different waveform.
Take sine as an example. The conversion relation between Vpp and
Vrms
fulfills the equation
Vrms Vpp 2 2
= .
dBm
and
Vrms
fulfills the equation
)
001 . 0
1
lg( 10
2
W R
Vrms
dBm
× = .
Wherein,
R denotes the output impedance of the channel and must be a
specific value; therefore, dBm cannot be used when the output impedance is
HighZ.
Return Format The query returns VPP, VRMS or DBM.
Example :SOUR1:VOLT:UNIT VPP /*Set the amplitude unit of CH1 to Vpp*/
:SOUR1:VOLT:UNIT? /*Query the amplitude unit of CH1 and the query returns
VPP*/