Specifications

Chapter 7 Trouble shooting
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(4) Alarm occurs during acceleration or deceleration:
◆ Cause 1: Excessive load inertia and the accelerating or decelerating time is too short.
⇒Remedy 1: Reduce the load inertia.
⇒Remedy 2: Set longer times for [tune mode]→[7: acceleration time constant] and [8:
deceleration time constant].
◆ Cause 2: Gain is set too high or too low
⇒Remedy 1: Adjust gains [parameter mode]→[0: speed loop gain], [1: speed loop integral
compensation] and [2: position loop gain].
Abnormal regeneration (release: imp.)
● Description
This alarm occurs when the thermal switch of the regeneration resistor in the HA-655 driver is activated
at 100℃. To release the alarm after troubleshooting, shut off the control power and turn it on again.
● Diagnostic tips
(1) Alarm occurs during deceleration
◆ Cause 1: The capacity of the regeneration resistor is too small.
⇒Remedy: Install an external resistor to make the capacity larger.
◆ Cause 2: The regeneration circuit of the HA-655 driver may have failed.
⇒Remedy: Contact Harmonic Drive Systems. (Replace the HA-655 driver)
Encoder failure (release: impossible)
● Description
This alarm occurs when the encoder signal ceases. To release the alarm after troubleshooting, shut off
the control power and turn it on again.
● Diagnostic tips
(1) Alarm occurs when the control power is turned on:
◆ Cause 1: The control circuit of the HA-655 driver may have failed.
⇒Remedy: Contact Harmonic Drive Systems.
(Replace the HA-655 driver)
◆ Cause 2: The encoder connector (CN1) may not be connected or may be improperly wired.
⇒Remedy: Verify connection of encoder connector (CN1) and connect it firmly.
◆ Cause 3: The encoder circuit may have failed.
⇒Remedy: Contact Harmonic Drive Systems.(Replace actuator)
(2) Alarm occurs during running (recovers after cooling of the actuator)
◆ Cause 1: Encoder malfunctions when the actuator temperature rises.
⇒Remedy: Review the actuator operating load, duty cycle, and its cooling system.