WEG ECW500, Руководство пользователя

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Functional Description .
40 | ECW500
measured AI
V
_
is the measured voltage at the analog input (parameter 40028);
rated EXC
I
_
is the rated excitation current of the synchronous machine set on the ECW500 (parameter 30066).
NOTA!
In the MECC mode, calculation of the reference by analog input only considers positive values of
the measured voltage. Negative values will result in a reference of 0A.
In the MRPC mode, the reference value that may be obtained through the analog input varies from -100% to
+100% compared to the rated voltage of the machine, in accordance with the following equation:
𝑄
𝑅𝑒𝑓_𝑀𝑅𝑃𝐶
= 𝐺𝑎𝑖𝑛
𝐴𝐼_𝑀𝑅𝑃𝐶
×
𝑉
𝐴𝐼_𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
10
× 𝑆
𝑟𝑎𝑡𝑒𝑑_3𝑝ℎ
In which:
MRPC AI
Gain
_
is the gain parameter for the analog input in the MRPC mode (parameter 30252);
measured AI
V
_
is the measured voltage at the analog input (parameter 40028);
rated_3ph
S is the three-phase rated apparent power of the synchronous machine set on the ECW500 (parameter
30068).
And in the MPFC mode, the value of the reference via analog input can be adjusted between -1.00 and 1.00,
according to the following equations:
𝑃𝐹
𝑅𝑒𝑓_𝑀𝑃𝐹𝐶
= 1.00 − (𝐺𝑎𝑖𝑛
𝐴𝐼_𝑀𝑃𝐹𝐶
×
𝑉
𝐴𝐼_𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
10
), 𝑡𝑜 𝐺𝑎𝑖𝑛
𝐴𝐼_𝑀𝑃𝐹𝐶
× 𝑉
𝐴𝐼_𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
≥ 0
𝑃𝐹
𝑅𝑒𝑓_𝑀𝑃𝐹𝐶
= −1.00 − (𝐺𝑎𝑖𝑛
𝐴𝐼_𝑀𝑃𝐹𝐶
×
𝑉
𝐴𝐼_𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
10
), 𝑡𝑜 𝐺𝑎𝑖𝑛
𝐴𝐼_𝑀𝑃𝐹𝐶
× 𝑉
𝐴𝐼_𝑚𝑒𝑎𝑠𝑢𝑟𝑒𝑑
< 0
In which:
MPFC AI
Gain
_
is the gain parameter for the analog input in the MPFC mode (parameter 30254);
measured AI
V
_
is the measured voltage at the analog input (parameter 40028).
In the MECC mode it is possible to use one of the analog inputs as a feedback signal. For this it is necessary to
change the parameter 31028 (External Power Module) to 1. Parameter 30256 (Full Scale for Excitation Current)
must be set to the value in Amps represented by the full scale of the analog output (10V or 20mA). Further
detailing of this functionality is presented on section 6.5.3.
NOTE!
If the PLCI (protection of the current input loss) is enabled and its reading falls below 3.5 mA, the
ECW500 will indicate broken wire failure. In this case, if the External Power Module parameter is set
to 1 the regulator will shut down.
If the analog input is not in use, you must disable this protection to prevent the error message from
being displayed.
NOTE!
There will be no influence from the analog input in the reference if the parameter 31048 is set to
option 0 (Parameter)