
Title 90A3 / 90A7 / 90B3 / 90B7
Learning Control Operator’s Manual
03 ’01.01.13 K.Maeda 3
rd
. updated. Draw No.
02 '03.01.06 K.Maeda 2
nd
. updated
A - 63639E - 070
01 ’00.09.20 K.Maeda Newly designed Sheet 050
Edit Date Design Description / 081
7.3.5 The limitation for maximum speed
• Maximum speed is limited by the performance of both servo software and encoder. Concerning encoder,
refer to the specification for encoder. On the other hand, there are the following speed limitation in servo
software.
In case of high gain setting ( cf. 5.2, velocity sampling 0.5msec., feedback sampling 0.125msec. )
1) The limitation by velocity control
Maximum speed = 32767 * 60 / tc / vpr = 1875 [min
-1
]
tc : feedback sampling [sec], vpr : velocity feedback pulse [2
23
pulse]
In feedback sampling, HRV1 control is tc=0.250msec. and HRV2 and HRV3 control are tc=0.125msec.
2) The limitation by position control
Maximum speed = 32767 * 60 / tv / ppr = 546 [min
-1
]
tv : velocity sampling [sec], ppr : position feedback pulse [7,200,000 pulse]
Therefore in this case maximum speed is limited by position control to 546 min
-1
.
• In the servo software 90B7 version 07 or later, there isn’t the limitation by position control during position
mode of PMC-axis speed command ( 10H + N8005#4=1 ). Therefore in this case maximum speed is
limited by velocity control to 1875 min
-1
. But you can’t use some functions, such as feed forward, backlash
acceleration, reference position return, learning control, during this mode.
•
In RCN723F encoder, there are some cases where count miss alarm occurs at high speed ( more than
200 min
-1
). In this case, this alarm can avoid by N2229#2=1. However such speed can’t be applied to
high precision processing because the detective accuracy isn’t guaranteed.