SLLU336A May   2021  – January 2022 MCT8316A

 

  1.   1
  2.   2
  3.   3
    1.     4
      1.      5
      2.      6
      3.      7
        1.       8
        2.       9
        3.       10
  4.   11
    1.     12
    2.     13
      1.      14
    3.     15
      1.      16
    4.     17
      1.      18
    5.     19
    6.     20
      1.      21
      2.      22
      3.      23
      4.      24
  5.   25
    1.     26
      1.      27
      2.      28
      3.      29
    2.     30
      1.      31
      2.      32
    3.     33
      1.      34
      2.      35
      3.      36
      4.      37
      5.      38
      6.      39
      7.      40
      8.      41
      9.      42
      10.      43
      11.      44
      12.      45
      13.      46

4.3.9 Protecting against rotor lock or stall condition

Follow below recommendations based on the type of fault triggered by MCT8316A.

Case 1: Follow below recommendations ff motor gets locked due to LOCK_LIMIT fault. Device triggers LOCK_LIMIT fault when the motor accelerates in closed loop or when the motor is overloaded.

Step 1: Increase lock detection current threshold [LOCK_ILIMIT]

Step 2: Increase the Lock detection current limit deglitch time [LOCK_ILIMIT_DEG] if the motor can withstand [LOCK_ILIMIT] for [LOCK_ILIMIT_DEG] time.

Step 3: Decrease CL_ACC.

Step 4: Enable dynamic degauss.

Case 2: Follow below recommendations if the device triggers CBC_ILIMIT, MTR_LCK, LOSS_OF_SYNC or ABN_SPEED.

Step 1: Increase CBC current limit

Step 2: Decrease CL_ACC.

Step 3: Enable dynamic degauss.

Case 3: If the motor vibrates and device fails to detect any fault, set the abnormal speed threshold to a value slightly above maximum speed. For example, if the maximum speed is 1000 Hz, set the abnormal speed threshold to 1100 Hz.

Case 4: If the motor generates high frequency noise and device fails to detect any fault, set the maximum degauss window [DEGAUSS_MAX_WIN] to either 15°or 18°. Default value is 22.5°.

Case 5: If the motor is loaded at lower speeds, MTR_LCK fault might get triggered when Min duty cycle is set too low. We recommend to se the Min duty cycle after loading the motor at lower speeds.

Note:

MCT8316A provides options to either latch LOCK_LIMIT fault or auto retry for [AUTO_RETRY_TIMES] after every [LCK_RETRY] seconds. This can be configured in LOCK_ILIMIT_MODE. We have defaulted the auto retry time and lock retry.