What are the precautions to use ATS22 / ATS48 soft starter with long motor cable in submersible pump application?

There is no special parameter setting in soft starter depending upon the cable length. But it is necessary to take care of some of points during its installation to avoid voltage drop and leakage current.
1. The motor cable length shall not be problem, if the motor cable is well sized and voltage drop is not causing inadequate current rise.
2. The voltage drop is proportional to the length of motor cable. Hence you should get confirmation from motor manufacturer that, "whether the motor will capable of driving the load with out any problem with the drop in voltage of 5 to 10%".
3. Please ensure the motor insulation is Class F and above to reduce the leakage current and improved thermal capability.
4. It is recommended to over size the soft starter rating adequately(at least 10 to 20% extra de-rating to other de-rating factors).
5. It is recommended to use the soft starter with end of bypass contactor. So that the internal losses due to thyristor switching is avoided during normal running.
6. Voltage drop during starting can be compensated by setting tq0 [initial voltage] to higher value (may be 30 to 50%)

Released for:Schneider Electric New Zealand