Which products are affected?
9300 vector 0.37 ... 90 kW software ≤ V6.3
9300 vector 110 ... 400 kW software ≤ V7.0
9300 hoist 0.37…75 kW software status ≤ V0.5
What happens?
After the flying restart (automatic speed detection C0142 = 2 or 3)
- the drive is starting unsmoothly (with torque or sudden change in current the overcurrent monitoring OC1 can be possible) or
- the vector control becomes unstable => maximum current (C0022) flows, there is, however, no torque at the motor shaft.
When does the problem occur?
If in operating mode 'vector control' (C0006 = 1) during the flying restart a short-term (< 2 s) controller inhibit occurs, e. g. when
- an internal monitoring (e. g. low voltage LU, overvoltage in the DC-link OU, ...) is activated
- on the control side (e. g. at terminal X5/28) the signal controller inhibit is set for a short while.
The incorrect behaviour can occur sporadically or every time the automatic speed detection has been activated.
The error
does not occur in case of voltage / frequency characteristic control.
Possible diagnostics?
Making an oscilloscope trance of the flying restart (the incorrect behaviour is shown in figure 1):
- MCTRL-N-SET2 (magenta; 50 %/DIV)
- MCTRL-F-ACT (red; 5 %/DIV)
- MCTRL-N-ACT (blue; 50 %/DIV)
- MCTRL-I-ACT (green; 20 %/DIV)
Short-term measures/recommendations?
Avoiding the short-term activation of the controller inhibit, e. g. by prolonging the signal 'controller inhibit' to 2 s (see e. g.
configuration example):
- Output DCTRL-CINH => Input TRANS1-IN
- Output TRANS1-OUT => Input DCTRL-CINH1
- Configuration FB TRANS1: C0710 = 0 (rising edge); C0711 = 2 s; C0465/45 = 10750 (TRANS1 in processing table)
Evaluation:
Until now the incorrect behaviour could only be seen at one application, where on the control side the speed drop has been detected during the flying restart and the controller has been inhibited for a short while. From software V7.0 (0.37-90 kW) on the incorrect behaviour is eliminated.
Figure: Faulty (figure 1) and correct (figure 2) flying restart, when the controller inhibit is set in the synchronizing phase for a short while.
Further information is provided in
Service Message No. 29/2005.
