Alstom MiCOM P846, Техническое руководство

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P846/EN CM/D Commissioning
(CM) 10-18
MiCOM P846
CM
Connections to the second rear port configured for EIA(RS)232 operation can be made using
a screened multi-core communication cable up to 15m long, or a total capacitance of
2500pF. The cable should be terminated at the relay end with a 9-way, metal shelled, D-
type male plug. The terminal numbers for the relay’s EIA(RS)232 port are given in Table 7.
Ensure that the communications baud rate and parity settings in the application software are
set the same as those in the relay. The relay’s Courier address in cell [0E90:
COMMUNICATIONS, RP2 Address] must be set to a value between 1 and 254. The second
rear communication’s port configuration [0E88: COMMUNICATIONS RP2 Port Config] must
be set to EIA(RS)232.
Check that communications can be established with this relay using the portable PC.
5.2.10 Current inputs
This test verifies that the accuracy of current measurement is within the acceptable
tolerances.
All relays will leave the factory set for operation at a system frequency of 60Hz. If operation
at 50Hz is required then this must be set in cell [0009: SYSTEM DATA, Frequency].
Apply current equal to the line current transformer secondary winding rating to each current
transformer input of the corresponding rating in turn, see Table 1 or external connection
diagram (P846/EN IN) for appropriate terminal numbers, checking its magnitude using a
multimeter/test set readout.
The measured current values displayed on the relay LCD or a portable PC connected to the
front communication port will either be in primary or secondary Amperes. If cell
[0D02: MEASURE’T SETUP, Local Values] is set to ‘Primary’, the values displayed should
be equal to the applied current multiplied by the corresponding current transformer ratio set
in the ‘CT and VT RATIOS’ menu column (see Table 6). If cell [0D02: MEASURE’T SETUP,
Local Values] is set to ‘Secondary’, the value displayed should be equal to the applied
current.
Note: If a PC connected to the relay via the rear communications port is
being used to display the measured current, the process will be
similar. However, the setting of cell [0D03: MEASURE’T SETUP,
Remote Values] will determine whether the displayed values are in
primary or secondary Amperes.
The measurement accuracy of the relay is ±1%. However, an additional allowance must be
made for the accuracy of the test equipment being used.
Cell in MEASUREMENTS 1 column (02)
Corresponding CT Ratio
(in ‘CT and VT RATIOS‘ column(0A) of
menu)
[0201: IA Magnitude]
[0203: IB Magnitude]
[0205: IC Magnitude]
Error! Bookmark not
defined.
[0A07 : Phase CT Primary]
[0A08 : Phase CT Secondary]
Table 8: CT ratio settings
5.2.11 Voltage inputs
This test verifies that the accuracy of voltage measurement is within the acceptable
tolerances.
Apply rated voltage to each voltage transformer input in turn, checking its magnitude using a
multimeter/test set readout. Refer to Table 7 for the corresponding reading in the relay’s
MEASUREMENTS 1 column and record the value displayed.