Lenze ECSCSxxx - Manual (Page 349)

Function library
Torque (torque control)
Torque control with speed limitation
12
l
349 EDBCSXS064 EN 4.0
12.28.1 Torque control with speed limitation
The "torque control with speed limitation" is the basic function of the "Torque" function
block. Thereby, only the current control loop (torque control loop) is in the axis module. The
torque setpoint is generated externally and is defined as a bipolar torque setpoint on
TORQUE−MCTRL.MAdd (C7531/1). Within the external setpoint source, there can possibly
be higher−level control loops (speed, position, pressure, ). "torque control with speed
limitation"#
By means of the specification of speed limits (speed limitation in the "Torque" function
block it is provided that the drive does not operate in an uncontrolled manner if the load
torque suddenly fails, e. g. due to a defect. The speed limits for positive and negative
directions of rotations can be altered dynamically. For this purpose, the unused speed
controller and a second speed controller (auxiliary speed controller) are used.
ƒ The speed controller 1 is used to make up the upper speed limit.
– The upper speed limit is defined at TORQUE−NSET.NSet (C7531/8) in [%] by N
max
(positive sign for CW rotation).
ƒ The speed controller 2 (auxiliary speed controller) is used to make up the lower
speed limit.
– The lower speed limit is defined at TORQUE−MCTRL.NStartMLim (C7531/5) in [%]
by N
max
(negative sign for CCW rotation).
ƒ N
max
is selected via code C0011.
(
Stop!
The upper speed limit is only to be used for CW rotation (positive values) and
the lower speed limit only for CCW rotation (negative values); otherwise the
drive may accelerate in an uncontrolled way.
)
Note!
The value at TORQUE−MCTRL.NegLoMLim (C7531/3) is negated in the "Torque"
function block.