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Ignoramus6355 Ignoramus6355 is offline
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Default Some success with a servo drive/tachometer mode

I started wiring everything in as professional manner as I am able to
do. I use DIN rail to mount as much stuff as possible, use DIN
terminals wherever possible, and I route wires through wire channels.

I connected my AMC 30A8T drive to the power supply and tachometer, so
that it would operate in tach mode. I made sure that all DIP switches
are set properly for tach mode.

Pictures of wiring are here.

http://igor.chudov.com/projects/Brid...iring-7670.jpg

The good news is that after some false tries, tach mode works
great. The X axis moves at about 70 IPM max, or super slow, as
commanded. I use a separate little power supply for commands. The
drive develops 68VDC and appx. 3 amps to move the table at highest
speed.

The more disconcerting news is that if a tach cable is not connected,
the drive goes into a runaway mode EVEN IF NO INPUT SIGNAL is
present (inputs shorted to each other).

This means that if I do a shoddy job wiring those tach contacts, or
the open barrel terminals fall out, or anything else, I will be in a
world of hurt.

I know that EMC has some protection against following error, but I am
not sure how robust is that.

Besides a lot of simple jobs facing me, I have a big job, which is
installing new encoders and making mount plates for same.

After this, I will try to create a "One-Axis CNC" machine without
worrying about other axes.

Anyway, I have one little thing to celebrate (the tach mode).

I also have a good grip on using that open barrel terminal crimper and
all crimps now come out looking good. I do a pull test on each, of
course.

i