Siemens sinamics dcp - 7.12 Precharging of the DC links

Operation
7.12 Precharging of the DC links
SINAMICS DCP
Operating Instructions, 09/2019, A5E34382853K
351
7.12 Precharging of the DC links
In the switched-off state, the DC link capacitors on side 1 and side 2 of the SINAMICS DCP
are in a no-voltage condition.
When the device is switched on, they must be charged up to the connected voltage sources
(e.g. DC link, battery, PV array).
This is referred to as precharging.
NOTICE
Current peaks
Directly connecting the DCP to a voltage source without precharging, results in high
equalization currents, and can destroy the device.
Precharging is controlled by the DCP. It is assumed that the appropriate switching devices
and precharging resistances are present in the system (not part of the scope of delivery),
and connected according to the following diagram "Connecting the resistance precharging at
both sides".
The parameters to be set can be seen in function diagram 6835 and are described in the
parameter list in the List Manual.
NOTICE
Malfunctions or damage if parameters are incorrectly set
Incorrectly set parameters (delay times, target value for precharging when pulsing up,
voltage tolerance) can result in malfunctions or damage to the system.
• Set the delay times (p55355[0,1], p55356[0,1]), the target value when precharging using
pulsing up (p55352) and the voltage tolerance (p55357) so that they match your
particular system.
There are two types of precharging:
● Resistance precharging
● Precharging using "pulsing up"
This results in the following precharging methods:
1. Resistance precharging at both sides
2. Resistance precharging at one side, pulsing up at the other side
Note
To ensure successful connection, the received DC
-link voltage or the battery voltage (target
value accordin
g to p55352) must have an accuracy of +/-2.5 % of the device rated voltage.