Mechanical Time Constant; 811 Mech. Time Constant S 0.000 - BONFIGLIOLI ACTIVE Applications Manual

5.1.1
The
from a standstill to rated speed with rated current.
Neglecting the friction,
T is the rated torque of the machine, J the entire mass moment of inertia of the drive.
n is the no load speed of the machine, thus resulting in the mechanical time constant
t
If the entire mass moment of inertia J is not exactly known, the mechanical time con-
stant t
For this, the plant constant
ing application is to be run without load at a constant speed (half rated speed of the
machine) (clockwise, lifting).
The actual value
Now, the lifting application is accelerated from standstill with the
wise)
(clockwise, lifting). Now, the actual value
If the value displayed for the estimated load is larger than the figure established be-
fore, the parameter value
opposite case, this figure must be reduced.
06/05
06/05

Mechanical time constant

mechanical time constant
:
m
can also be determined by an acceleration test.
m
Load
242 is noted.
420 required in operation to a speed above the rated speed of the machine
Parameter
No. Description
811 Mech. time constant
811 is the time which the drive needs to accelerate
dω
T = J ⋅
dt
dω
dt = J ⋅
T
n
⋅ 2 ⋅ π = ω
60
J ⋅ n ⋅ 2 ⋅ π
t =
m
T ⋅ 60
Turns per meter
812 must be set first. After this, the lift-
Estimated load
mechanical time constant
Min.
0.000 s
Acceleration (clock-
243 is evaluated.
811 must be increased. In the
Setting
Max. Fact. sett.
65.000 s 0.190 s
17
17