PIU Operation
ANCA Motion
D-000129 Rev 09
101
9
9
PIU Operation
9.1
What this Chapter Contains
This chapter contains information related to typical operating conditions of the PIU and expected data for these
conditions
9.2
PIU Introduction
The Passive Infeed Unit (PIU) provides power to all the Drives by converting 3 phase mains to a filtered DC
supply which is distributed to the servo drives on common bus. The PIU uses a half controlled bridge rectifier to
slowly charge the DC Bus capacitors in the PIU and Drives. Once the capacitors are charged, the DC output
voltage varies according to the supply mains voltage and load power.
The PIU also distributes the customer supplied 24 Vdc control voltage to all drives, provides a LED power supply,
and interfaces via EtherCAT.
Figure 9-1: Block diagram of the PIU system
