Fujitsu BS2000 SE Series Operating Manual page 8

Additive Components
Depending on the hardware base, Application Units differ as follows:
Application Unit PY refers to all PRIMERGY based AUs (e.g. the AU20 or AU47 hardware models).
Application Unit PQ refers to all PRIMEQUEST based AUs (e.g. the AU87 or DBU87 hardware models).
This section covers the following topics:
Application Unit PY (SE AU PY)
Application Unit AU25
Application Unit AU47
Front of the Application Unit
Rear of the Application Unit
Application Unit PQ (SE AU PQ)
Switching an Application Unit on/off
Operating system and other software
System operation
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