REM (Customer) asked a question.
New line reactor(s) causing VFD's to trip on startup
Our engineers decided we needed to add line reactors to our Siemens VFD's. They consulted Siemens and had them size the reactors. After installing the first one, when the VFD is given a start command it trips, but doesnt show a reason. They have tried different reactors, and installed them on different (same size) drives always with the same results. I will be working this problem beginning in the next day or so and am curious what others may think. Right now I am wondering if the drives are creating an upstream harmonic and it is bouncing of the reactor, but if that is whats happening I would expect the drive to be showing an overvoltage fault. Thoughts please?
What is the carrier frequency? Try to reduce it to 5K and less. Other than that if it is wired proper I can't think of a reason why it would do that.
Is the line reactor before the VFD, or is it actually wired as a load reactor after the VFD output terminals between the VFD and motor?
It should work fine either way, but I could imagine a scenario where used as a load reactor the VFD could not understand the new load characteristics and think something is wrong if the parameters are not set up loose enough.
I did not see the fault you are describing, but when I was connecting the output side of the reactor to the input side of my drive, (LR-4040 input side to GS4-4040) I was having problems fitting the 4AWG crimp terminals into the sockets provided (by the way, the GS documentation says min wire gauge is 2awg but the reactor is 4awg?)
anyway the L1 and L2 terminal connections on the input side of the line reactor were loose and barely grabbing the tip of the wire. You could see the indention in the tip of the solid copper wires where only half the retaining bolt head had made contact. The solid copper wires should be very rigid and you shouldn’t be able to wiggle them at all.
maybe as simple as a loose connection on the reactor out of the box. I’m not knocking the product, boxes get tossed around in the shipping process and you have to check wverything
If this is a vector drive, has it been autotuned with the new reactor installed?