• In Pr. 22, set the stall prevention operation level. Normally set it to 150% (factory setting). Set "0" in Pr. 22
to disable the stall prevention operation.
• To reduce the stall prevention operation level in the high-frequency range, set the reduction starting
frequency in Pr. 66 and the reduction ratio compensation factor in Pr. 23.
Formula for stall prevention operation level
Stall prevention operation level (%) = A + B × [
Pr.66 (Hz) × Pr.22 (%)
where, A =
output frequency (Hz)
• By setting "9999" (factory setting) in Pr. 23, the stall prevention operation level is constant at the Pr. 22
setting up to 400Hz.
• Set "9999" in Pr. 22 to vary the stall prevention operation level using the analog signal (0-5V/0-10V)
entered to the frequency setting auxiliary input terminal . (Use Pr. 73 to select between 10V and 5V.)
• Use Pr. 148 and Pr. 149 to adjust the gain and bias of the analog signal.
• Set "0" in Pr. 154 to reduce the output voltage during stall prevention operation.
Note: 1. When Pr. 22 = "9999", terminal 1 is exclusively used for setting the stall prevention operation
level. The auxiliary input and override functions are not activated.
2. When high-response current limit is set in Pr. 156 (factory setting), do not set the Pr. 22 value to
170% or higher. If such setting is made, torque will not be developed.
Do not set a too small value as the stall prevention operation current. Otherwise,
torque generated will reduce.
Test operation must be performed. Stall prevention operation during acceleration may
increase the acceleration time.
Stall prevention operation during constant speed may change the speed suddenly.
Stall prevention operation during deceleration may increase the deceleration time,
increasing the deceleration distance.
Pr. 24 to Pr. 27
Refer to Pr. 4 to Pr. 6.
4.2.13 Multi-speed input compensation (Pr. 28)
Pr. 28 "multi-speed input compensation"
By entering a compensation signal into the frequency setting auxiliary input terminal 1 (Note 2), the speeds
(frequencies) of multi-speed settings or the speed setting made by remote setting function can be
Note: 1. Use Pr. 73 to select the compensation input voltage between 0 to ±5V and 0 to ±10V.
2. When any of "4, 5, 14 and 15" is set in Pr. 73, the compensation signal is entered into terminal 2.
Pr.66 (Hz) × Pr.22(%)
0: Not compensated,
Pr. 4 to Pr. 6, Pr. 24 to Pr.27, Pr. 232 to
Pr. 239 (multi-speed operation)
Pr. 59 "remote setting function selection"
Pr. 73 "0-5V/0-10V selection"