On 2013-06-15, Gunner Asch wrote:
On Tue, 11 Jun 2013 19:08:11 -0500, "Pete C."
wrote:


Karl Townsend wrote:

[ ... ]

Now he's surfing fleabay for a couple VFDs.

Karl

Why a couple of VFDs? You'll never use the hor and vert spindles at the
same time so one VFD will do fine for both.


The problem is turning them on and off. NEVER switch the output line
from a VFD..ever. Only switch the Input (power) TO the VFD

Doing it wrong lets out the magic smoke.

The trick is "never switch the output side of a VFD while it is
powering a motor. If it is halted, you can swithc over to another
motors before spinning it up again. (What you need is an interlock so
the VFD has to be at "halt" before you can switch to a new motor.) But
two VFDS are nicer, anyway.

Enjoy,
DoN.

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