Mitsubishi Electronics MR-J2S- A instruction manual CAUTION

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3. SIGNALS AND WIRING
(5) Torque limit
CAUTION If the torque limit is canceled during servo lock , the servomotor may suddenly
rotate according to position deviation in respect to the command position.
(a) Torque limit and torque
By setting parameter No. 28 (internal torque limit 1), torq ue is always limite d to the maximum
value during operation. A relationship between the limit value and servo motor torque is shown
below.
00 100
Max. torque
torque
Torque limit value [%]
A relationship between the applied voltage of the analog torque limit (TLA) and the torque limit
value of the servo motor is shown below. Torque limit values will vary about 5% relative to the
voltage depending on products.
At the voltage of less than 0.05V, torque may vary as it may not be limited sufficiently. Therefore,
use this function at the voltage of 0.05V or more.
2k 2k
Servo amplifier
Japan resistor
RRS10 or equivalent
TL
SG
P15R
TLA
LG
SD
100
0
010
5%
0.05
Torque limit value [%]
TLA application voltage vs.
torque limit value
TLA application voltage [V]
(b) Torque limit value selection
Choose the torque limit made valid by the internal torque limit value 1 (parameter No. 28) using
the external torque limit selectio n (TL) or the torque limi t made valid by the analo g torque limit
(TLA) as indicated below.
When internal torque limit selec tion (TL1) is made usable by parameter No. 43 to 48, internal
torque limit 2 (parameter No. 76) can be selected. However, if the parameter No . 28 value is le ss
than the limit value selected by T L/TL1, the parameter No. 28 value is made valid.
(Note) External input signals
TL1 TL Torque limit value made valid
0 0 Internal torque limit value 1 (parameter No. 28)
01 TLA Parameter No. 28: Parameter No. 28
TLA Parameter No. 28: TLA
10 Parameter No. 76 Parameter No. 28: Parameter No. 28
Parameter No. 76 Parameter No. 28: Parameter No. 76
11 TLA Parameter No. 76: Parameter No. 76
TLA Parameter No. 76: TLA
Note. 0: off
1: on
(c) Limiting torque (TLC)
TLC turns on when the servo motor torque reache s the torque limited using the internal tor que
limit 1 2 or analog torque limit.