Beckhoff EL3413-0000, Документация

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Commissioning
EL34x3 134 Version: 4.4
5.5.1.1 Reference channel for the frequency measurement and power/energy
measurement
In the EL34x3 all 3 channels are always selected independently of one another as reference for the
frequency measurement or power/energy measurement. In order to avoid an error message from the
terminal, the channels that are not in use should be deactivated.
The correct channels can be selected with the help of the predefined PDOs. Beyond that individual phases
can be switched on or off with the help of the Command Object (index
0xFB00:01 [
}
153] ).
5.5.1.2 Measuring cycle time
Number of periods taken as the basis for the calculation of the true RMS value. The higher this value the
more uniform the output values. A minimum of 4 periods is necessary; however a minimum of 5 periods is
recommended.
The default value of 10 periods has proven to be a good compromise between stability and speed.
The measuring cycle time can be changed with the help of the Command Object (index 0xFB00:01 [
}
153] ).
The command is started by writing subindex 1 (request). Write access is disabled until the current command
is completed.
0x0022 Measuring interval 4 periods
0x0122 Measuring interval 5 periods
0x0222 Measuring interval 10 periods (default)
0x0322 Measuring interval 16 periods
0x0422 Measuring interval 32 periods
Sample
In order to change the measuring interval to 16 periods, the value 0322
hex
must be entered in Index
0xFB00:01 [
}
153] .
The adoption of the new measuring cycle time can take up to 10 seconds. The value is not stored in the
EEPROM; following a voltage reset of the terminal a measuring cycle time of 10 periods is set again. In order
to avoid this, the value can be set with the help of a startup parameter.
5.5.1.3 Current measuring range
The EL34x3 offer three current measuring ranges
*)
. The full scale value of the current can set to 5 A, 1 A or
0.1 A for the EL3413-xxxx and to 10 A, 2 A or 0.2 A for the EL3433-xxxx. The correct setting of the full scale
value is important in order to avoid unnecessary measurement inaccuracies. It is recommended to always
measure in the upper third of the full scale value.
*) EL3413-0000: From HW10, FW07; 100 mA from KW35/2015;
EL3413-0120: From HW10, FW04;
EL3413-0001, EL3433 from release
Sample
In order to change the full scale value to 5 A on the EL3413-xxxxx, the value 500
dec
must be entered in index
0x802D:11 [
}
153] .
In the case of the EL3433-xxxx, the value 1000
dec
must be entered in index 0x802D:11 [
}
153] for 10 A.
NOTE
Risk of damage to the device!
Exceeding the full scale value can lead to incorrect measurement results and to damage to the terminal.