Assistance with a flexible VFD installation
The time has come to bring power to my hembrug lathe and I need some advice about selecting the right vfd, there is quite a lot I am grey on and the ebay listings for VFD's havent really cleared much up. What i hope to have is as follows.
It needs to drive a 3hp star/delta motor sourced off Joe H here.
I have full 415v three phase available in the factory currently, but in future the machine may come home with me, it would be nice to not need to buy another VFD. But it doesnt seem like many VFDs are designed for both cases but someone may know of a special snowflake.
I would like to incorporate the machines remote fwd / off / rev switch and a braking resistor but im having a hard time sizing and finding the right braking resistors. Also should reversing be handled at a logic level or by flipping the polarity after the VFD as per it would have originally. Im guessing the back EMF would be nasty.
The other thing is it would be nice to replicate the original 3 speed ranges, can this be done with fixed value resistors in addition to the traditional pot? or do they generally only have one input for speed? I guess i could garry it so that the pot is switched out and the fixed value resistors in? im assuming the speed circuit is run at something sane like 3.3 or 5v?
I am absolutely not an expert, when I do come to do this I will have someone experienced over my shoulder but i would like to have all the right lego first.
Regards - Ralph