METREL MI 2893 User Manual

MI 2893 / MI 2892 / MI 2885 Measurement methods
180
All voltage measurements represent RMS values of the voltage magnitude over a 10/12-cycle time
interval. Every interval is contiguous, and not overlapping with adjacent intervals.
L1
L3
L2
N
GND
U1
U2
U3
UN
U12
U23
U31
Figure 149: Phase and Phase-to-phase voltage
Voltage values are measured according to the following equation:
Phase voltage:



M
j
j
pp
u
M
U
1
2
1
[V], p: 1,2,3,N
(1)
Line voltage:



M
j
j
g
j
p
uu
M
Upg
1
2
)(
1
[V], pg.: 12,23,31
(2)
Phase voltage crest factor:
p
pPk
Up
U
U
CF 
, p: 1,2,3,N
(3)
Line voltage crest factor:
pg
pgPk
Upg
U
U
CF 
, pg: 12, 23, 31
(4)
The instrument has internally 3 voltage measurement ranges, which are automatically selected
regarding to the nominal voltage.
5.1.3 Current measurement (magnitude of supply current)
Standard compliance: Class A (Section 5.13)
All current measurements represent RMS values of the samples of current magnitude over a 10/12-cycle
time interval. Each 10/12-cycle interval is contiguous and non-overlapping.
Current values are measured according to the following equation:
Phase current:



M
j
j
pp
I
M
I
1
2
1
[A], p: 1,2,3,N
(5)
Phase current crest factor:
Ip
Ip
Ip
cr
max

, p: 1,2,3, N
(6)
The instrument has internally two current ranges: 10% and 100% range of nominal transducer current.
Additionally, Smart current clamps models offer few measuring ranges, automatic clamp detection and
automatic range selection.

METREL MI 2893 Specifications

General

Brand	METREL
Model	MI 2893
Category	Measuring Instruments
Language	English