YASKAWA Varispeed f7, Programming Manual

Page: 94 / 202

Programming 86
This multi-function digital input is used to switch the Drive between speed control and torque control. The function is only
available in flux vector control method (A2-01 = 3). Parameter D5-01 must be set to 0 and an analog input terminal (A2 or A3)
must be programmed for function “13: torque reference”.
When the programmed terminal is open (off), the Drive will operate in speed control. The speed reference source is determined by
parameter b1-01. The torque limit used is the smaller of the analog input limit (if an analog input is programmed for function 10, 11,
12, or 15), the torque limit parameter value (L7 group), or the absolute value of the analog input programmed for function “13: torque
reference”, which acts as a 4-quadrant torque limit. There are multiple torque limits for each quadrant. If the run command is
removed during speed control, the Drive will stay in speed control and stop according to parameter b1-03. For ramp to stop, the Drive
will use the active torque limit as described above.
When the programmed terminal is closed (on), the Drive will operate in torque control. The torque reference will come from the
analog input terminal (A2 or A3) programmed for function “13: torque reference”. The speed limit is determined by parameter
d5-03. If d5-03 = 1, the speed limit used is the output of the soft starter as determined by b1-01, the analog input settings for A2 or
A3, the active accel/decel time, and the s-curve settings. If d5-03 = 2, the speed limit is determined by parameter d5-04. If a stop
command is received during torque control, the Drive will automatically switch to speed control and stop according to parameter
b1-03. For ramp to stop, the Drive will use the active torque limit as described above.
Function: Zero Servo Command
Setting: 72
Zero-servo function provides position control capability at zero speed. When zero-servo is enabled by closing the programmed
multi-function input, and the output frequency is less than the DC injection start frequency (b2-01), the shaft position is maintained
by monitoring PG feedback pulses and correcting the position error. However, this function does not have the same capabilities of a
position controller because there is no marker pulse feedback. Therefore, the motor will not stop in the same position every time the
zero servo command is enabled.
Function: ASR Gain Switch
Setting: 77
This multi-function digital input is used to switch between ASR Gain 1 (C5-01) and ASR Gain 2 (C5-03). The function is only
available in Flux Vector control method (A1-02 = 3). The ASR gain switch function has priority over the ASR switchover
frequency parameter (C5-07). It will ramp fro one gain to the other using the active ASR integral time. The use of the ASR
gain switch allows for two different machine/motor responsiveness set-ups. This can be used for breaking loose a high friction
load at start, acceleration versus constant speed, two different products running on the same machine, etc.
Function: Polarity Reversing Command
Setting: 78
This multi-function digital input is used to switch the polarity of the analog torque reference command (multi-function analog
input function “13: Torque Reference / Limit”). The function is only available in Flux Vector control method (A1-02 = 3). The
Drive must be in torque control by either setting D5-01 = 1 or setting D5-01 = 0 and closing the multi-function digital input
function “71: Speed / Torque Changeover”. This function does not affect the signal when the Speed / Torque Changeover input
is open (speed mode with the analog signal acting as a torque limit). This function is valid for either analog input
terminal (A2 or A3) and any input signal level (4 to 20 mA, 0 to 10V, +/- 10V). When in torque control, the direction of the
motor rotation is determined solely by the polarity of the torque reference command. This function provides for easy switching
of the motor direction.