On Thu, 19 Aug 2010 21:49:38 -0500, Ignoramus12820
wrote:

I finally added an extra instruction to "inhibit" the drives when the
axes were not position controlled. Now, if EMC is stopped due to
following error, or I turned the motion off, the drives are inhibited
and would not do anything.

i

Do you have them inhibited if the watchdog timer expires due to a
software crash / hang?

If watchdog timer expires, the all output of Jon's PPMC shuts down,
and that turns off the main motive power contactor. There is no
problem with that.

I really should try to simulate a system crash while moving, for
example by pulling a power cord.

I would STRONGLY recommend putting in a couple relays on the power lines
going to the servos. When machine power goes out..it instantly opens the
relays and prevents the servos from running away for a second or two as
the power supply caps discharge.

My customers busted a bunch of tooling because of that not being
implimented in OmniTurns the first couple years.

Gunner

--


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