171
(7) Encoder communication error
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Display
】
【
Description of detected alarm
】
Communications with the internal encoder of the servo motor fails.
【
Causes and Solutions
】
Causes
Solutions
Error in encoder serial
communications
• Check cables visually and through continuity check and correct
faults.
• Check for the broken wire in the encoder cable and correct if broken.
• Insert ferrite cores.
Broken wire or poor contact
The servo motor drive and encoder communicate through high speed serial communications.
The encoder signal has a voltage amplitude of about 5 V. Do not route the encoder cable in a strong magnetic
or electric field. Route the encoder cable separately from the main body of the servo motor drive, inverter,
electromagnetic contactor or similar (reserve at least 100 mm).
(8) EI Error
【
Display
】
【
Description of detected alarm
】
There is duplication in allocation of EI input terminals of the servo
motor drive.
【
Causes and Solutions
】
Causes
Solutions
The same input signal is allocated to
two or more terminals.
Do not specify the same number among EI signal settings.
(9) Overload
【
Display
】
【
Description of detected alarm
】
• OL1: Alarm that detects failures such as a locked shaft
instantaneously. (3s/300%)
• OL2: The effective torque exceeds the allowable limit of the servo
motor. (Detection at electronic thermal relay built in servo motor
drive)(about 200s/200%)
【
Causes and Solutions
】
Causes
Solutions
The servo motor fails to rotate
mechanically.
• Check the wiring of power cables (U, V and W) and correct faults.
• Check if the brake is active.
The mechanical system is too heavy
against the servo motor capacity.
• Examine the servo motor capacity, based on the load factor.
• If the rotation speed can be reduced, add a reduction gear.
• Apply the brake to retain a stopped elevator.