-7-
V
．
Measuring Principle
1. Voltage to ground measurement adopts average value rectification method.
2. Earth resistance measurement with fall-of-potential method. AC constant
current
I
(3mA Max, 820Hz) is applied between the measurement object
E
(earth electrode) and
C
(current electrode), and finding out the potential
difference V between
E
and
P
(potential electrode).
Rx=V/I
3
．
Maximum Operating Error
：
Operating error(B) is an error obtained within the
rated operating conditions, and calculated with the intrinsic error(A), which is
an error of the instrument used, and the error(E) due to variations.
A
：
Intrinsic error
E1
：
Variation due to position change
E2
：
Variation due to power supply voltage
E3
：
Variation due to
temperature change
E4
：
Variation due to interference voltage change
E5
：
Variation due to contact electrode resistance
E7
：
Variation due to system frequency change
E8
：
Variation due to system voltage change
Summary of Contents for HZRC-3000
Page 2: ......
