The output frequency may be limited due to limit operation such as current limit. If the acceleration torque is insufficient F07 (Accelerating time 1), the acceleration time is lengthened. If the output torque is insufficient, use F09 (Torque boost 1) to raise the torque boost value. Others like F43 (Current limit (operation selection)), F44 (Current limit (operation level)) and reviewing the load condition may solve the problem.
One point advice
With factory shipment setting, the value F43 , F44 is "operation". When current exceeding the current limit operation level flows, limit operation is performed and the frequency decreases. H64 (The factory set value of the lower limiter (minimum frequency at the time of limit operation)) is 1.6 [Hz], so frequency may be stagnated around 2.0 [Hz] due to limit operation.
Operation selection ( F43 )
Select the operating state in which the current limit function operates.