Bosch Rexroth IndraDrive HMV01.1R-W0045 - Page 74

8-2 Determination of Appropriate Power Supply Units Rexroth IndraDrive
DOK-INDRV*-HMV-*******-PR01-EN-P
If the duration over which the drive is operated at constant speed is
considerably greater than the accel and decel time, then it applies:
n21
nn2211
av
t...tt
t*n...t*nt*n
n
++
+++
=
n
av
: average motor speed [min
-1
]
n
1
... n
n
: motor speed [min
-1
]
t
1
... t
n
: ON time [s]
Fig. 8-2: Average speed; influence of accel and decel time is not taken into
consideration
DGoE.fh7
n
1
n
2
n
3
t
1
t
2
t
3
t
4
t
Abb. 8-3: Speed cycle; influence of accel and decel time is not taken into
consideration
Accel and decel times with short cycle times must be taken into
consideration in such dynamic applications as is the case with rollers and
nibble machines:
2B1H
B1H
av
tttt
t*
2
n
t*nt*
2
n
n
+++
++
=
n
av
: average motor speed [min
-1
]
n: motor speed [min
-1
]
t: time [s]
t
H
: accel time [s]
t
B
: decel time [s]
Fig. 8-4: Average speed; influence of accel and decel time is taken into
consideration
DGmE.fh7
n
t
1
t
2
t
t
H
t
B
Abb. 8-5: Average speed; influence of accel and decel time is taken into
consideration
Average speed without accel
and decel time
Average speed with accel and
decel times