Yaskawa Matrix Converter - Manual (Page 344)

Troubleshooting
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‹ Motor Deceleration is Too Slow
Use the following information when the motor deceleration is slow.
The deceleration time is too long.
Check the deceleration time setting (parameters C1-02, C1-04, C1-06, and C1-08).
Motor torque is insufficient.
If the parameters are correct and there is no overvoltage fault, then the motor’s power is limited. Consider
increasing the motor capacity.
The torque limit has been reached.
When a torque limit has been set in parameters L7-01 to L7-04, no torque will be output beyond that limit.
This can cause the deceleration time to be too long. Check to be sure that the value set for the torque limit is
suitable.
If H3-09 (Terminal A2 Function Selection) or H3-05 (Terminal A3 Function Selection) is set to 10, 11, 12 or
15 (positive and negative torque limit), check to be sure that the analog input value is suitable.
„ Vertical-Axis Load Drops when Brake is Applied
The sequence is incorrect. The MxC goes into DC injection braking status for 0.5 seconds after deceleration is
completed (this is the factory-set default).
To ensure that the brake holds, set Frequency Detection 2 (H2-01 = 5) for the multi-function digital output ter-
minals (M1 and M2) so that the relays will switch off when the output frequency is greater than L4-01 (3.0 to
5.0 Hz). The contacts will switch on again when the output frequency falls below L4-01.
There is hysteresis in Frequency Detection 2 (i.e., a frequency detection width, L4-02 = 2.0 Hz). Change the
setting to approximately 0.5 Hz if there are drops during stop. Do not use the multi-function digital output run
signal (H2-01 = 0) for the brake on/OFF signal.
‹ Motor Overheat
Take the following steps if the motor overheats.
„ The load is too big.
If the motor load is too heavy and the motor is used with the enabled torque exceeding the motor's rated
torque, the motor will overheat. Some motor rating are given for short period performance and are not contin-
uous ratings. Reduce the load amount by either lightening the load or lengthening the accel/decel time. Also
consider increasing the motor capacity.
„ The ambient temperature is too high.
The motor rating is determined within a particular ambient operating temperature range. The motor will burn
out if it is run continuously at the rated torque in an environment in which the maximum ambient operating
temperature is exceeded. Lower the motor's ambient temperature to within the acceptable ambient operating
temperature range.