Motor starting frequency
Motor starting frequency
(OP)
What is the meaning of the following in relation to pump starting:
Motors shall withstand at least:
3 consecutive starts, at 80% Un, with load inertia according to IEC60034-12.
Motors shall withstand at least:
3 consecutive starts, at 80% Un, with load inertia according to IEC60034-12.





RE: Motor starting frequency
1 The motors should be able to withstand 3 consecutive starts. This requirement would be for larger motors. Many large motors are limited to 2 starts per hour. This is especially true if they have a high inertia load which would cause the motor to have an extended start time.
2. The 80% Un...I assume this refers to the minimum starting voltage of 80% of nameplate. That's a common minimum allowable starting voltage.
3. I'm not familiar with IEC standards.
RE: Motor starting frequency
RE: Motor starting frequency
I am asking mainly from interest - I have not seen the requirement "80% Un, with load inertia according to IEC60034-12" - before and searching through IEC60034 -12 did not enlighten me at all.
RE: Motor starting frequency