Instruction manual

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3. SIGNALS AND WIRING
(b) Analog torque command offset
Using parameter No. PC38, the offset voltage of
999 to 999mV can be added to the TC applied
voltage as shown below.
0
8( 8)
Max. torque
Generated torque
TC applied voltage [V]
Parameter No. PC38 offset range
999 to 999mV
(2) Torque limit
By setting parameter No. PA11 (forward torque limit) or parameter No. PA12 (reverse torque limit), torque
is always limited to the maximum value during operation. A relationship between limit value and servo
motor torque is as in (5) in section 3.4.1. Note that the analog torque limit (TLA) is unavailable.
(3) Speed limit
(a) Speed limit value and speed
The speed is limited to the values set in parameters No. PC05 to PC11 (internal speed limits 1 to 7) or
the value set in the applied voltage of the analog speed limit (VLA).
A relationship between the analog speed limit (VLA) applied voltage and the servo motor speed is
shown below.
When the servo motor speed reaches the speed limit value, torque control may become unstable. Make
the set value more than 100r/min greater than the desired speed limit value.
Forward rotation (CCW)
Reverse rotation (CW)
-10
Rated speed [r/min]
CCW direction
0+10
VC applied voltage [V]
CW direction
Rated speed
Speed[r/min]
The following table indicates the limit direction according to forward rotation selection (RS1) and reverse
rotation selection (RS2) combination:
(Note) External input signals Speed limit direction
Analog speed limit (VLA)
RS1 RS2
Polarity Polarity
Internal speed
commands
10 CCW CW CCW
01 CW CCW CW
Note. 0: off
1: on
Generally, make connection as shown below:
SP1
SP2
DOCOM
P15R
VC
LG
SD
2k
2k
Servo amplifier
Japan resistor
RRS10 or equivalent
(Note)
For the sink I/O interface. For the source I/O interface, refer to Section 3.8.3.
Note.