Yaskawa F7 Drive Programming Manual - Manual (Page 54)

Programming 46
The direction in which speed is controlled is determined by the sign of the speed limit signal and the direction of the run command.
Positive voltage applied: The speed in the forward direction will be limited for forward operation.
Negative voltage applied: The speed in the reverse direction will be limited for reverse operation.
If the direction of the motor rotation and the command direction are not the same, speed will be limited to zero as long as d5-
05 is set to zero. The direction of the run command determines the polarity of the speed limit.
Example:
Fmax - E1-04 = 60 Hz
Speed limit bias - d5-05 = 10%
No load on motor - Drive will always run up to speed limit
Speed Limit Bias Setting
The speed limit bias can be set to limit both the forward and reverse speed to the same value. This differs from the operation of
the speed limit bias setting. To use the sped limit bias, set d5-04 to 0 and set the bias in d5-05 as a percentage of the maximum
output frequency.
To set 50% forward and reverse speed limits, set the speed limit setting to 0 (d5-03 = 2, d5-04 = 0, and d5-05 = 50). The range
of torque control will be from -50% to 50% of the maximum output speed.
When using both the speed limit and the speed limit bias, the range of torque control will be positive and negative speed limits
with the speed limit bias added to each.
The range of torque control when the forward speed limit is 50% and the speed limit bias is 10% as shown in the following
figure. This figure does not take the priority circuit into account.
Fig. 36 Speed Limit Bias Setting
Run Direction Torque Reference Output Frequency
FWD 100% 46Hz
FWD -100% -6Hz
REV 100% 6Hz
REV -100% -46Hz
P ositive Torque
N egative Torque
R everse O peration Forw ard O peration
Speed lim it bias
d5-05
d5-05
D elta N = Tref % / C 5-01
d5-04
Reverse Operation
Positive Torque
Speed limit bias
d5-05
Delta N = Tref % / C5-01
Forward Operation
d5-04 d5-05
Negative Torque