Re: How to connect Rutex drive to Gettys DC servo controller?

The connections described look very similar to ones on some Gettys
Drives on a mill I have from circa 1981. The drawing describes this
as a Model N360 three phase half-wave servo controller. Drawings
have numbers very similar to the number Juha listed in his initial
post. here's what's on the connection diagram I have from Gettys:

+24 vdc is unregulated, 250 ma max, for external customer use

EN+ enables forward bridge

EN- enables reverse bridge

X1,2,&3 line voltage in
X0 line neutral

A1, A2 servo motor connections

Tach mounted to motor....connections back to Tach terminals

There is a section in the schematic titled "power regulator" which
feeds +15vdc and -15vdc to all modules

Is an SCR amp, as schematic refers to SCR packs 1, 2, 3

It appears the reference voltages from the computer are fed into a
card entitled "speed integrator"

This is all I can add, as I'm a member of the electronically
challenged. Maybe Jon or someone can make some use of it. If I
might be able to find something else in the drawings that would be
useful, just let me know. I don't know where to look to add
anything further.

Cliff

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Jon Elson <elson@p...> wrote:
>
>
> Juha Keisala wrote:
>
> >Thanks Jon,
> >
> >A power source is connected direcly to thyristors??? likewise the
> >output to motors with a wire thick as a little finger.
> >
> >
> Well, AC LINE sounds like the power input.
>
> >On the drive it is written SCR SERVO CONTROLLER, does this mean a
> >thyristor controller?
> >
> >
> Yes, VERY old servo amps were made using thyristors. SCR is
another
> name for the thryristor trademark (GE, I believe). They generally
had very
> low bandwidth.
>
> >Could you exlain the terminal 14 connection again, I did not get
it.
> >First of all, what is an armature in this case, where exacly the
> >armature should be connected to and when? Do you mean the winding
in
> >the rotor that should be shorted with a resistor, but when? Do
you
> >mean when turning of the auxiliary of the controller or??
> >
> >
> I have no idea. I am totally guessing. You asked what wire to
hook where,
> based entirely on the labels on the cabinet. I made educated
guesses,
> but they
> are just guesses. The moving part of a DC brush motor is called
the
> armature.
> To bring such a motor to a stop, a resistor can be placed across
it. I was
> guessing that the DB relay was for dynamic braking when the drive
was
> powered off or E-stop was pushed. The resistor should be connected
> across the two motor terminals when this condition happens. I was
guessing
> that the relay would be wired to connect the resistor when the
relay coil
> was powered off, as a fail-safe mechanism. That is entirely a
GUESS.
>
> >How about therminal 11. Should I leave the tachometer into the
motor
> >and leave it connected inspite of the encoder I have to add for
the
> >Rutex?
> >
> >
> The amp, if it is a velocity servo, needs the tachometer to
measure
> velocity.
> It would have no use for a tachometer if NOT a velocity servo. If
the
> original
> motors had a tachometer, then the amps need this without
reconfiguring them.
>
> >Terminals 5, 13 and 17 are conneted to each others with external
wire.
> >I'll try to find out is no. 5 in or out
> >
> >
> I really think there is little chance of this working without
further
> documentation. The performance of such amps is likely to be pretty
> bad. The Rutex adaptor may not even be able to be tuned for stable
> operation with a servo amp of such low bandwidth. And, if it is as
> you say with thyristors wired directly between the line and the
motor,
> the safety concerns are quite serious. Maybe it requires an
external
> transformer for isolation.
>
> Jon