ABB ACS880-04 drive modules, Application Manual

Page: 20 / 48

20 Planning – basics
Symbol Name Information
P
mot
Motoring power Power that the motors take from the common DC link
P
mot,ave
Average motoring
power Average power that the motors take from the common DC link. See the
duty cycle diagram of the common DC link.
Note: For long cycles
times, define P
mot,ave
over the worst-case 3 minutes time window.
P
mot,max
Maximum motoring
power Maximum power that the motors take from the common DC link. See
the duty cycle diagram of the common DC link.
P
gen
Generating power Power that the motors supply to the common DC link
P
gen,ave
Average generating
power
Average power that the motors feed to the common DC link when they
are in generating mode (braking the load). See the duty cycle diagram
of the common DC link.
Note: If you will use the brake choppers of the
drives in the system, determine P
gen,ave
over the worst-case 30
seconds time window.
P
gen,max
Maximum
generating power Maximum power that the motors feed to the common DC link when they
are in generating mode (braking the load). See the duty cycle diagram
of the common DC link.
P
rec
Rectifier power Power that the drive input bridges (rectifiers) feed to the common DC
link. See section
Selecting the drives which are connected to
AC power line on page 21 for the calculation instructions.
P
rec,ave
Average rectifier
power capacity The drives that are connected to the AC power line can feed this
average power to the common DC link.
P
rec,max
Maximum rectifier
power capacity The drives that are connected to the AC power line can feed this power
to the common DC link at the maximum.
P
br
Braking power Surplus power that the brake resistors take from the common DC link.
(Alternatively: Power that the drive feeds to the AC power line if a
regenerative type of drive is in use.) See section
Handling the surplus
energy on page 25 .
P
br,cont
Continuous braking
power Continuous braking power that the brake resistors take from the
common DC link. The braking is continuous if the braking time exceeds
30 seconds.
P
br,max
Maximum braking
power Maximum braking power that the brake resistors take from the common
DC link. Brake choppers withstand this braking power for 5 second
within every minute.