Speed Limit Detection Signal (/Vlt) - YASKAWA SGMJV User Manual

4 Operation

4.8.8 Speed Limit Detection Signal (/VLT)

4.8.8

Speed Limit Detection Signal (/VLT)

This function limits the speed of the servomotor to protect the machine.
A servomotor in torque control is controlled to output the specified torque, but the motor speed is not con-
trolled. Therefore, if an excessive reference torque is set for the load torque on the machinery side, the speed
of the servomotor may increase greatly. If that may occur, use this function to limit the speed.
Note: The actual limit value of motor speed depends on the load conditions of the servomotor.
Motor speed
Maximum speed
The parameters related to the speed limit, such as for selecting the speed limit method, are described next.
(1) Signals Output during Servomotor Speed Limit
The following signal is output when the motor speed reaches the limit speed.
Type
Output
Note: Use parameter Pn50F.1 to allocate the /VLT signal for use. For details, refer to 3.3.2 Output Signal Allocations.
(2) Speed Limit Setting
Select the speed limit mode with Pn002.1.
Pn002
4-56
With No Speed Limit
Danger of damage due to
critical speed.
Time
Signal Connector
Name Pin Number
/VLT Must be allocated
Parameter
VLIM (the speed limit value during torque control) is
n.0
not available. Uses the value set in Pn407 as the speed
[Factory setting]
limit (internal speed limit function).
VLIM operates as the speed limit value (external speed
n.1
limit function).
With Speed Limit
Motor speed
Limiting speed
Setting
ON (closed) Servomotor speed limit being applied.
OFF (open) Servomotor speed limit not being applied.
Meaning
Safe operation with
speed limit.
Time
Meaning
When
Classification
Enabled
After restart Setup