AFE inverters are aligned inversely to the supply and are not capable of functioning autonomously. In order to function, they need at least the following system components:
For the compact units
- VSB voltage sensing board
- Main contactor
- AFE reactor
For safety reasons, an AFE rectifier/regenerative unit must be connectedto the supply via a line contactor. An external 24 V power supply is therefore always necessary for supplying the VSB board and the AFE inverter.
For the chassis units
- AFE supply connecting module
In order to facilitate handling when chassis units are used, all the necessary system components together with some supply componente, icluding the Clean Power filter, are combined to form an AFE supply connecting module.
Clean Power filter
Whereas the Clean Power filter is generally necessary for the chassis units (sizes E to G) it is optional in the case of Compact units.
For very small line transformers, i.e. for a power ratio of PAFE to PTrans = 1:5, use of this filter is recommended, (e.g. if PAFE = 6.8 kW, a Clean Power filter should be used whre the line transformer output < 34 kVA).
Basic interference suppression board
The basic interference-suppression board must be used if an EMC filter has not been configured so that at least basic EMC interference-suppression is ensured. It is only permissible to use this board on earthed supply systems.