47113964.2.023РЭ
24
Table 17. Zero-sequence Voltage and Zero-sequence Current Tests
Voltage, %
of the nominal value
Current, %
of the nominal value
Phase angle, degree Current phase
relative to the
voltage, degree
U
A
U
B
U
C
I
A
I
B
I
C
φ
А
φ
B
φ
С
100
100
100
100
100
100
0
-120 120
0
50
100
100
50
100
100
0
-120 120
0
0
100
100
0
100
100
0
-120 120
0
100
100
100
100
100
100
0
120 120
0
100
100
100
100
100
100
0
0
0
0
-
Set the nominal input signal to the AET400 in accordance with 1.2.2. section; set the frequency of
the input signal ( 45; 50; 55; 60; 65 Hz) by turns; read the output code at the «ComplexMet 3 EN» and
calculate frequency value by inverse function of transformation. In case of alternation of the adjacent
codes the most deviating value should be read.
- Calculate the intrinsic error (
γ
) expressed as a percentage of the fiducial value in all check
points in conformity with 3.4.3.4.
Limits of the measurand’s intrinsic errors are in the table 6.
After the test, switch off the input signal source, press the «Stop» button in the «ComplexMet 3 EN»
window. End the program «ComplexMet 3 EN» and then cut off the auxiliary supply.
3.4.3.7 The following operations should be executed testing of intrinsic error of the three-wire system:
-
Complete the operations in accordance with 3.4.3.5 under three-wire system.
-
Start the «ComplexМet 3 EN». Load the work configuration file at the « File» menu.
-
Configure appropriate parameters in the «RS-485» Menu and «ModBus» Menu.
-
Configure appropriate nominal voltage and current values in the «Nominal value» Menu in
accordance with transducer’s model.
-
Press “Start” button in the «ComplexMet 3 EN» window.
-
Apply the nominal input signal to the transducer in accordance with 1.2.2.
-
Let the transducer standby for 10 minutes before taking the first reading to thermally stabilize.
-
Set input signal parameters which are specified in tables by turns in accordance with 14, 15 or
16 tables. Read the output code at the «ComplexMet 3 EN» and calculate measurand value by inverse
function of transformation. In case of alternation of the adjacent codes the most deviating value
should be read.
- Calculate the intrinsic error (
γ
) expressed as a percentage of the fiducial value in all check
points in conformity with 3.4.3.4
Limits of the measurand’s intrinsic errors are in the table 6.
After the test, cut off the input signal source, press the «Stop» button in the «ComplexMet 3 EN» win-
dow. End the program «ComplexMet 3 EN». Next, cut off the auxiliary supply.
3.4.3.8 The relative value of a ratio between an aggregate error of a standard and the intrinsic
error of the gauged transducer should not exceed 1/3.
The greatest adoption probability of the unsuitable transducer as suitable is 0.1.
The greatest permissible value of the ratio transducer’s intrinsic error to a limit of the supposed
intrinsic error is 1.2, when the unsuitable transducer is adopted as suitable.
