Emco 120p Control hardware suggestions

Hi all!

As topic explains i have taken on a Emco turn 120P retrofit.
Bought it with a broken controller so i have replaced all electronics (almost) on it and i have come to the point were my next step is wiring everything up and for that i need a hardware solution for the controller bit.

i have previously worked with bridgeport, DMG machines, both mill and lathe but after switching work i no longer have access to that, now i have some machines at home and at work and they run of Mach3 or UCCNC and i can't stand the constant reliability hassle with Mach3. UCCNC works pretty good but they don't have a lathe section. so after a lot of reading it seams LinuxCNC is the way to go if you want good results and reliability.

i have read a lot of forum threads etc. and the solution almost everyone recommends is MESA Electonics, i have been in contact with MESA, and EUSurplus (since i live in Sweden) but i have not got the help i needed to get the best solution for me.

This is what i have put in my machine:

Closed-loop steppers Nema34 4.5nm with matching drivers
Bevi AC 3ph motor 3Kw
ENC 3ph 3.7Kw vector VFD
2x Proximity switches for homing on X/Z
Toolerator 3000 (Big thanks to Tome for sharing this!)

what i have kept is the solenoids for the pneumatic part and the original spindle encoder.

so now for the big question what do i need to make this work?

i need a computer and the controller cards for this i have nothing i currently own that i will try to use.

the most important thing for me is reliability, i will not use this machine for production only hobby use but i hate the machine does random things.

i would say my budged for the controller cards is around $200 (excluding a pc) $250 is possible but after that it is starting to hurt

a pretty straight forward solution would be the 7I76-6I25 PLUG-N-GO KIT or possibly a 7I76E STEP/IO Step & dir plus I/O daughtercard.

however as soon as you involve the encoders of the X/Z steppers things starts to be complicated quite quick. and the answer i get is get an 7I85S-6I25 PLUG-N-GO KIT with an additional 7184 card and this solution get's quite costly..

Are there any better alternatives?

and for the computer part what do you recommend?

I'm thankful for all the help i get!

Best regards Victor

Well, there is the Pico Systems Universal Stepper Controller, which accepts encoder inputs by flipping a switch.
For spindle speed control, you can add the Spindle DAC. That will total $300, and should be all you need.
It attaches via a parallel port, so if you don't have one, you can get a PCI or PCIe plug-in card.
See pico-systems.com/osc2.5/catalog/product_...ath=3&products_id=19
for more info.

Jon

jmelson wrote:

Well, there is the Pico Systems Universal Stepper Controller, which accepts encoder inputs by flipping a switch.
For spindle speed control, you can add the Spindle DAC. That will total $300, and should be all you need.
It attaches via a parallel port, so if you don't have one, you can get a PCI or PCIe plug-in card.
See pico-systems.com/osc2.5/catalog/product_...ath=3&products_id=19
for more info.

Jon

The Universal stepper controller looks like a good system but a little out of my comfort zone at $300, but absolutely an alternative if i don't find any other solution.

Br Victor

andypugh wrote:

You might have all the IO you need with just a parallel port. You can probably get away with just a single "fault" input from the closed-loop drives.
It might be sensible to start off that way and get a feel for what you need prior to investing in alternative hardware.
The spindle encoder will probably lose synch at high spindle speeds if counted using software, but you don't tend to do spindle-synched moves like threading at high spindle speeds anyway.
If the VFD communicates with Modbus that can be very convenient, USB to Modbus dongles are very cheap indeed.

Ok intresting so i could use a PC with and DB25 connector and a simple DB25 BOB for starters?

i know i have an alarm signal output from my stepper driver.

What would be a good choice pc wise? i have read that people have had success with the ASRock Q1900B-ITX motherboard
The above card already have the DB25 connector will it work for LinuxCNC?

how would i wire the spindle encoder? just use an input pin?

My VFD has Modbus/RS485 so an dongle sound pretty sweet.

Br Victor

andypugh wrote:

Victor wrote:

how would i wire the spindle encoder? just use an input pin?

It would require 3 input pins. (A, B and Index) and the software encoder module:
linuxcnc.org/docs/2.7/html/man/man9/encoder.9.html

Ok. i don't think the encoder has an index pin. here is a link with some explanation of the encoder Emco spindle encoder

the encoder uses GND and +5V and outputs 1ppr & 360ppr signal(s)

i was aiming at using just the 1ppr output for starters and at a later date upgrade to an quadrature encoder.

Br Victor

Haha ok silly of me, yes the 1ppr would be the index.

yes 1000 rpm should be sufficient for threading.

could you share any experience on possible solutions for the PC?

Thanks!

Br Victor