Agilent Technologies Turbo-V 551 Rack Notice De Mode D'emploi page 244

17 Technical Information
Window Meanings
Soft Start
"Soft Start" mode is provided to start the pump after a protracted
stop of the Turbo 551 Pump. This allows a better grease distribution
in the bearings.
The "Soft Start" mode is disabled by default. The "Soft Start" mode
can be activated by a suitable software, by Remote I/O or by Front
Panel command (see the paragraphs "INTERCONNECTIONS" and "RS
232/485 COMMUNICATION DESCRIPTION"). "Soft Start" frequency
steps are the followings: 150 Hz, 250 Hz, 350 Hz, 450 Hz, 550 Hz and
715 Hz. The pump remains at each step for a period of 300 s. A fail
condition occurs if the pump is not able to properly spin up the
driving frequency (Too High Load Error).
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