Hi,
I just bought four Delta B2 series AC servos and I had been trying to program them by button pushing...it is
possible but you make so many mistakes. I had to buy a specialist cable, in the event I bought a genuine the
Delta accessory. It has made life SO MUCH easier, aside from all the tuning aids built in.
When VFDs come from the factory they are usually set up for 50Hz or 60Hz motors being the industry standard use for
VFDs. If you hook up your 400 Hz spindle WITHOUT programming the correct parameters first you will blow either
the spindle or the VFD or both!
What most people fail to realize is that a VFD is essentially a voltage to frequency converter.The control voltage is 0-10V.
The output voltage will vary as the frequency changes, this is called the V/F curve. With the VFD as setup from the factory
if you apply 10V input the out put will be 60Hz at full voltage namely 230VAC three phase. Your spindle will hate that,
its supposed to get full 230VAC three phase but at 400Hz, if you apply full voltage at only 60Hz the current will be through
the roof, the coils inside the spindle will be horribly magnetically saturated and BAD things will happen.
Amongst the programming parameters are the max frequency, most users find that and set it to 400Hz but don't realize
that there are other parameters that set the voltage at intermediate frequencies.
Lets take a really simple example. If your spindle is rated at 230VAC at 400 Hz then at 200 Hz you would apply half the voltage,
namely 115VAC, at 40Hz you would apply 1/10 of full voltage namely 23VAC. This is a simple linear V/F curve.
There are rather more sophisticated V/F curves but provided you get the idea that the output voltage must drop as the
frequency lowers then you will have no run-away currents and bad things won't happen.
Craig