Agilent Technologies Turbo-V 551 Rack Notice De Mode D'emploi page 224

17 Technical Information
Connection J1 Remote I/O Interconnections
Connection P2 EXTERNAL FAN
This is a dedicated 24 Vdc connector to supply the optional external
fan kit through a suitable optional extention cable (see Orderable
Parts table).
See Window Meaning table and HOW TO USE BY FRONT PANEL
chapter to know the external fan possible settings.
Figure 15
ref.8 in figure above
NOTE
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