Function extension:
The following possible settings have been added to the parameter for setting the rated mains voltage (0x2540.1):
0x2540:1 = 10: 230V - low undervoltage threshold
0x2540:1 = 11: 400V - low undervoltage threshold
0x2540:1 = 12: 480V - low undervoltage threshold
When selecting the additional possible settings, the undervoltage threshold (LU) can be set to lower values.
In this way, controller operation can be maintained for a longer time, e.g. if the power supply is interrupted in the case of a mains failure.
Important note:
When using the extended DC voltage range (reduced LU threshold), the user must ensure that the mains will not only be interrupted for a short time.
If necessary, an early mains recovery must be prevented by appropriate circuitry measures. The mains must only be switched on again when the DC voltage has fallen below the LU threshold. Only then, the charging current limitation will be active again when switching on the mains.
The charging current limitation is not switched on during operation. In the case of mains recovery and operation in the low DC voltage range, there would be a very high recharging current and the controller might be damaged due to the lack of current limitation.
Contained in which products?
i700 servo inverter from V01.07.05.10577
Application:
In the event of a power supply failure (mains failure), the machine shall be decelerated to standstill as quickly as possible and in a controlled manner.
For this, you can use the 'Mains failure control' principle. The energy that is resupplied during braking in generator mode is used to maintain the DC voltage in the DC bus and accordingly the braking operation as long as possible.
With the lower LU threshold reduction, the DC voltage range usable for active braking can be extended.
