Panasonic A4P Series Manuel D’Utilisation

166

Current through the converter portion has exceeded 
the specified value.
1)Failure of servo driver (failure of the circuit, IGBT or 

other components)

2)Short of the motor wire (U, V and W)

3)Earth fault of the motor wire

4)Burnout of the motor 

5)Poor contact of the motor wire.

6)Melting of the relays for dynamic brake due to 

frequent Servo-ON/OFF operation 

7)The motor is not applicable to the driver.

1)Turn to Servo-ON, while disconnecting the motor. If 

error occurs immediately, replace with a new driver.

2)Check that the motor wire (U, V and W) is not 

shorted, and check the branched out wire out of the 
connector. Make a correct wiring connection. 

3)Measure the insulation resistance between motor 

wires, U, V and W and earth wire. In case of poor 
insulation, replace the motor.

4)Check the balance of resister between each motor 

line, and if unbalance is found, replace the motor.

5)Check the loose connectors.  If they are, or pulled 

out, fix them securely. 

6)Replace the driver. Prohibit the run/stop operation 

with Servo-ON/OFF.

7)Check the name plate and capacity of the motor and 

driver, and replace with motor applicable to the driver. 

Temperature of the heat sink or power device has been 
risen over the specified temperature. 
1)Ambient temperature has risen over the specified 

temperature.

2)Over-load                      

1)Improve the ambient temperature and cooling 

condition.

2)Increase the capacity of the driver and motor.
  Set up longer acceleration/deceleration time.
  Lower the load.

Torque command value has exceeded the over-load 
level set with SV.Pr72 (Overload level) and resulted in 
overload protection according to the time 
characteristics (described later)
1)Load was heavy and actual torque has exceeded the 

rated torque and kept running for a long time. 

2)Oscillation and hunching action due to poor 

adjustment. Motor vibration, abnormal noise.  Inertia 
ratio (SV.Pr20) setup error. 

3)Miswiring, disconnection of the motor. 

4)Machine has collided or the load has gotten heavy. 

Machine has been distorted. 

5)Electromagnetic brake has been kept engaged.

6)While wiring multiple axes, miswiring has occurred by 

connecting the motor cable to other axis.

7)SV.Pr72 setup has been low.

Check that the torque (current) does not oscillates nor 
fluctuate up an down very much on the graphic screen 
of the PANATERM

®

. Check the over-load alarm display 

and load factor with the PANATERM

®

.

1)Increase the capacity of the driver and motor. Set up 

longer acceleration/deceleration time. Lower the load.

2)Make a re-adjustment.

3)Make a wiring as per the wiring diagram. Replace the 

cables. Connect the black (W phase), 

   white (V phase) and red (U phase) cables in 

sequence from the bottom at the CN X2 connector.

4)Remove the cause of distortion. Lower the load.

5)Measure the voltage between brake terminals. 

Release the brake 

6)Make a correct wiring by matching the correct motor 

and encoder wires.

7)Set up SV.Pr72 to 0. (Set up to max. value of 115% 

of the driver)

Regenerative energy has exceeded the capacity of 
regenerative resistor. 

1)Due to the regenerative energy during deceleration caused 

by a large load inertia, converter voltage has risen, and the 
voltage is risen further due to the lack of capacity of 
absorbing this energy of the regeneration discharge resistor.

2)Regenerative energy has not been absorbed in the 

specified time due to a high motor rotational speed. 

3)Active limit of the external regenerative resistor has 

been limited to 10% duty.

Check the load factor of the regenerative resistor on 
the monitor screen of the PANATERM

®.

 Do not use in 

the continuous regenerative brake application.
1) Improve the regenerative processing capability, e.g., 

increase the motor and driver capacity, put external 
regenerative resistor, etc.

2) Reduce the regenerative energy at deceleration, 

e.g., lower the motor rotation speed, make the 
deceleration time longer, etc.

3) If SV.Pr6C (External regenerative resistor set up) is 

“0” and an internal regenerative resistor is used, and 
if SV.Pr6C is “3” and an external regenerative 
resistor is not used, use the external regenerative 
resistor and try to set SV.Pr6C to “1”.

   If the external regenerative resistor is used and 

SV.Pr6C is set to “1”, secure any external over-
regeneration load protection measures and try to set 
SV.Pr6C to “2”.

<Remarks>
Install an external protection such as thermal fuse without fail when you 
set up SV.Pr6C to 2. Otherwise, regenerative resistor loses the protection 
and it may be heated up extremely and may burn out.