ABB ACS 600 Supplement To Firmware Manual page 25

60.03 WINDOW SEL ON
ACS 600 Master/Follower Application Macro
MAXIMUM
The torque selector compares the torque reference and the speed
controller output (see Figure 4-1), the greater of which is used as the
reference for motor torque control. MAXIMUM is selected in certain
special cases only. External control location 2 (EXT2) must be active to
make the MAXIMUM selection effective.
ADD
Torque selector adds the speed controller output to torque reference
(see Figure 4-1). The drive is torque controlled in normal operating
range. External control location 2 (EXT2) must be active to make the
ADD selection effective.
The selection ADD, together with the window control, forms a speed
supervision function for a torque controlled Follower drive as follows:
• In normal operating range, the Follower follows the torque reference
(TORQ REF 1).
• Window control keeps the speed controller input and output at zero
as long as speed error (speed reference - actual speed) remains
within a certain window (see Figure 4-2 below).
• If the speed error moves out of the window, window control connects
the error to the speed controller. The speed controller output
increases or decreases the internal torque reference, stopping the
change of the actual speed (see Figure 4-2).
ZERO
This selection fixes the output of the torque selector to 0.
Window control, together with selection ADD at Parameter 60.02
TORQUE SELECTOR, forms a speed supervision function for a torque
controlled drive. External control location 2 (EXT2) must be active to
enable window control. If external control location 1 (EXT1) is chosen,
the drive is speed-controlled without window control.
NO
Window control is off.
YES
Window control is on. This selection should be used only when
Parameter 60.02 TORQUE SELECTOR is ADD. Window control
supervises the speed error value (Speed Reference - Actual Speed). In
normal operating range window control keeps the speed controller
input zero. The speed controller is evoked only if:
• the speed error exceeds the value of Parameter 60.04 WINDOW
WIDTH POS or
• the absolute value of the negative speed error exceeds the value of
Parameter 60.05 WINDOW WIDTH NEG.
Chapter 4 – Parameters
4-7