Replacing old Mitsubishi analog AC servos with new step/dir ones.

Hi,
any idea what to use as a replacement for
4x Mitsubishi MR-E-70AG-KH003 AC servo drivers
4x Mitsubishi HF-KN73J-S100 servos mated to APEX AB090-S1-P1 gearboxes turning a rack and pinion style system

I would like to ditch the analog 0-10V control system for a new one that's step/direction. Sure I could buy just new MR-E-70A-KH003 drivers but since 4 of those cost the same as 4 new Chinese AC servos (that are new unlike the approx 10-12 years old Mitsubishi servos) it might be better idea to just upgrade?

Anyone willing to chime in and recommend me a brand besides Leadshine/Leisai? I think I would prefer a 23-bit servos.

Also as I view it there is a few ways I could do this, right?
Ditch just the servos, buy new AC servos and keep the gearboxes. (Probably the best solution?)
Ditch both the servos and the gearboxes and buy Chinese ones.
Ditch the servos and the gearboxes and replace them with closed-loop steppers (this is the cheapest way but might not be the best).

If the existing drives are working, i would try hard to use them.
Till now always succeded but once.
But in case you change them, do get sets that are tuned already, to much stuff there so might end up not where you want to.
Also mind the gearbox coupling to new motors, where i live, such mechanical work is non existent.

MR-E-AG drives are position controlled with step/direction, they do not have speed control mode with 0-10V analog input...

There is also the option of keeping the motors (which are likely to be high-quality and a good match to the other mechanics) and just replacing the drives.

But what is your motivation for the change? LinuxCNC has good support for analog +/-10V servo systems.

dm17ry wrote:

MR-E-AG drives are position controlled with step/direction, they do not have speed control mode with 0-10V analog input...

Are you sure? Quoting from the manual

The analog input MR-E-***AG-KH003 Servo Amplifier is based on the MR-E-***A-KH003 Servo Amplifier with capability of speed control and torque control.

AKA the "AG" is analog and "A" is the digital (step/dir) one, no?
And I have the AGs.

you're right, my bad. AG seems to be a later model and they put analog inputs wiring description to the end of the manual