Cause
Possible Solutions
The drive is set for both 2-Wire
and 3-Wire sequence at the same
time.
• The drive is set for a 3-Wire sequence when one of parameters H1-03 through H1-05 is set to 0.
• If the drive is supposed to be set up for a 2-Wire sequence, then ensure parameters H1-03 through H1-05 are not
set to 0.
• If the drive is supposed to be set up for a 3-Wire sequence, then H1-
must be set to 0.
n
Motor Rotates in the Opposite Direction from the Run Command
Cause
Possible Solutions
Phase wiring between the drive and motor is incorrect.
• Check the motor wiring.
• Switch two motor cables (U, V, and W) to reverse motor direction.
• Connect drive output terminals U/T1, V/T2 and W/T3 in the right order to the corresponding
motor terminals U, V, and W.
• Change the setting of parameter b1-14.
The forward direction for the motor is setup
incorrectly.
Typically, forward is designated as being counterclockwise when looking from the motor
shaft (refer to the figure below).
1
2
1. Forward Rotating Motor (looking down the motor shaft)
2. Motor Shaft
Note:
Check the motor specifications for the forward and reverse directions. The motor specifications will vary depending on the manufacturer
of the motor.
n
Motor Rotates in One Direction Only
Cause
Possible Solutions
The drive prohibits reverse rotation.
• Check parameter b1-04.
• Set the drive to allow the motor to rotate in reverse (b1-04 = “0”).
A Reverse run signal has not been entered, although 3-
Wire sequence is selected.
• Make sure that one of the input terminals S3 to S5 used for the 3-Wire sequence has been
set for reverse.
n
Motor is Too Hot
Cause
Possible Solutions
The load is too heavy.
If the load is too heavy for the motor, the motor will overheat as it exceeds its rated torque
value for an extended period of time.
Keep in mind that the motor also has a short-term overload rating in addition to the possible
solutions provided below:
• Reduce the load.
• Increase the acceleration and deceleration times.
• Check the values set for the motor protection (L1-01, L1-02) as well as the motor rated
current (E2-01).
• Increase motor capacity.
The air around the motor is too hot.
• Check the ambient temperature.
• Cool the area until it is within the specified temperature range.
Insufficient voltage insulation between motor phases.
When the motor is connected to terminals U/T1, V/T2, and W/T3, voltage surges occur
between the motor coils and drive switching.
Normally, surges can reach up to three times the drive input power supply voltage (600 V for
200 V class, and 1200 V for 400 V class).
• Use a motor with voltage tolerance higher than the max voltage surge.
• Use a motor designed to work specifically with a drive when using a 400 V class unit.
• Install an AC reactor on the output side of the drive.
The motor fan has stopped or is clogged.
Check the motor fan.
n
Motor Stalls During Acceleration or With Large Loads
Cause
Possible Solutions
Load is too heavy.
Take the following steps to resolve the problem:
• Reduce the load.
• Increase the acceleration time.
• Increase motor capacity.
• Although the drive has a Stall Prevention function and a Torque Compensation Limit
function, accelerating too quickly or trying to drive an excessively large load can exceed
the capabilities of the motor.
n
Motor Will Not Accelerate or the Acceleration Time is Too Long
Cause
Possible Solutions
Frequency reference is too low.
• Check the maximum output frequency (E1-04).
• Increase E1-04 if it is set too low.
Check U1-01 for proper frequency reference.
Check if a frequency reference signal switch has been set to one of the multi-function input terminals.
Check for low gain level set to terminal A1 (H3-03).
6.8 Troubleshooting without Fault Display
SIEP C710606 33A OYMC AC Drive – J1000 User Manual
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6
Troubleshooting
