Fluke 8050A - RMS Converter

AC
SIGNAL
(±Vi)
GIVEN: Vrms
=
..fVr
THEN: Vrms
2
=
Vi
2
Vrms
=
Vi
2
Vrms
r
AcsuF'FER'AMPs'l
I
I I
±Vi
I
I I
I
GAIN
I
I
I
CONTROL
I I
X1,X10,X100
L
--
- -
_J
ACX1
ACX100
6
FROM MICROCOMPUTER
=
THEORY
OF OPERATION
TRUE-RMS CONVERTER
Where
Vi
is
the instantaneous
ac
voltage.
anti
log
(log
Vi
2
=
antilog
(2
log Vi -
log
Vrmsl
Vrms
ABSOLUTE
TO
A/D
CONVERTER
VALUE
CIRCUIT
Vrms
!Vil
ANTI
LOG
LOG
CONVERTER
CONVERTER
2X
LOG
2 log Vi
log
Vrms
CONVERTER
Figure 3-6. RMS
Converter
3-9/3-10