Power Stack Adapter; Current Transformer; Fans; Figure 3-4 Example: Power Stack Adapter - Siemens SINAMICS GL150 Operating Instructions & Installation Instructions

Description
3.3 Power unit
3.3.1.5

Power Stack Adapter

Figure 3-4
The power stack adapter (PSA) acts as an interface between the power unit and the open-loop/
closed-loop controller. The Power Stack Adapter is also where the power unit is electrically
isolated from the open-loop/closed-loop controller. The DRIVE-CLiQ serial communication
interface ensures the exchange of data between the Power Stack Adapter and Control Unit
(CU).
In the Power Stack Adapter, the switching information predefined by the Control Unit is
translated into firing pulses (long pulses). The firing pulses are converted to optical signals and
sent to the thyristor electronics via fiber-optic cables. This initiates firing readiness in the
thyristor electronics and activates a monitoring and interlocking logic circuit. The thyristor
electronics then determine the operating status of the thyristor and relays it to the Power Stack
Adapter via the checkback fiber-optic cable. The control commands and checkback signals
correlate with each other. Any disruption to this relationship, for example an open circuit in an
FO conductor or a failed thyristor, is relayed to the open-loop/closed-loop control system as an
error message.
3.3.1.6

Current transformer

Current transformers are used to measure current. The analog output signals from the current
transformer are post-processed by the AVT combination module and sent via the fiber-optic
cable to the power stack adapter. The primary circuit is separate from the secondary circuit.
3.3.1.7

Fans

The fan is mounted on the cabinet. The fan draws in air through the ventilation slots in the door
from the immediate vicinity of the cabinet. The fan blows the air radially into the ambient area.
A contactor and a motor protection switch protect the fan against overload.
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Example: Power Stack Adapter
SINAMICS GL150 6SL38502UM114PA0Z
Operating Instructions Rev.201910281441 EXAMPLE