ABB ACQ580, Руководство по прошивке

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64 Program features
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Soft pump control (SPFC)
The Soft pump control (SPFC) logic is a variant of the PFC logic for pump and
alternation applications where lower pressure peaks are desirable when a new
auxiliary motor is to be started. The SPFC logic is an easy way to implement soft
starting of direct on line (auxiliary) motors.
The main difference between traditional PFC and SPFC logic is how the SPFC logic
connects auxiliary motors on-line. When the criteria for starting a new motor is fulfilled
(see above) the SPFC logic connects the drive controlled motor to the supply network
in a flying start, that is, while the motor is still coasting. The drive then connects to the
next pump unit to be started and starts controlling the speed of that one, while the
previously controlled unit now is connected directly on line through a contactor.
Further (auxiliary) motors are started in a similar manner. The motor stopping routine
is the same as for the normal PFC routine.
In some cases SPFC makes it possible to soften the start-up current while connecting
auxiliary motors on-line. Lower pressure peaks on the pipelines and pumps may be
achieved as a result.
Settings
• Parameter group 10 Standard DI, RO (page 117 )
• Parameter group 40 Process PID set 1 (page 213 )
• Parameter groups 76 Multipump configuration (page 256 ) and 77 Multipump
maintenance and monitoring (page 267 ).