and another rotary table question.

[hangslot]

I have a HRT 160 Rotary table, with a DC-brush motor, that I would like to run on a machine with Fanuc 0i control.
When I open the front, I can see the back of the motor, its the 20.11.1.36-4175B ElEC MTR ASSY HA5C WP.
Is there somebody who know anything about this?

Thanks, Herman

[hydrospin01]

If I understood you correctly you wanna know if it's possible. I'm thinking you'll need to have a servo control unit to go with that so the two systems will be able to communicate but you may need to contact haas to know for sure. Fanuc builds there control systems with many features unfortunetly not all of them are turned on, so even though your control system is 4th axis capible it may not be 4th axis ready. I would contact your machines manufacturer and ask what option your machine has. If it is not 4th axis ready Fanuc will turn the option on for you, but for a price. Hope this is of some help to you.

[NC Cams]

Here's what I've learned of late after loads of recent research into adapting an HRT-160 w/DC motor to my V2XT Bridgeport, including a discussion with a factory engineer (BTW, not easy to get to):

They use a 2000 count 6 lead 5vdc TTL level servo encoder that has A, A-, B, B-, I, I- on their DC brush motor fitted tables.

They also have "brake solenoid engage leads" (two, I dunno the voltage rating) and a 5v TTL output signal output for "home" and "brake engaged" (it appears that the signal voltage being fed to the TTL stage is same 5vdc like that fed to the encoder but can't confirm.

They also have a chassis ground and +/- to the DC motor to feed it high power.

NOTE AND VERY IMPORTANT TO YOUR SITUATION: THEY DO NOT HAVE TACH FEEDBACK FROM THEIR MOTOR so don't bother looking for it.

Reason: they appear to be using the encoder signal and their computer system to close the loop on motor speed feedback . They use a proprietary servo amp as far as I can tell. This could be a real problem for you - as it was for me and for the same reason. Namely, I (like you) need a tach feedback voltage with our servo amps and our CNC controllers.

Moreover, Haas is NOT interested in doing custom retrofits outside of perhaps giving out pin info IF you can get to the right people - thus, forget changing the motor unless you can find out who actually made the motor (someone besides Haas probably did) and swap it out or add a tach to it (if you do, please let me know how you did it).

Haas engineering will categorically reject custom motor requests (as in providing their motor with a tach). Reason: they're running full tilt making "stock, bolt together Haas items" and can barely keep up - they essentially have absolutely NO capacity or desire for making or supporting special/one off tables, especially ones that may ultimately be bolted to a Fanuc or Bridgeport control.

If you do NOT buy their $1000 motor control box as the interface between your machine and the HRT-160, the table may NOT run with your Fanuc servo amp, especially if you can't find a way to get a tach feedback signal of the proper range and polarity.

It MAY be possible to craft up a F-V converter (Analog Devices has several chips to do it). These should take a pulse train from one of the encoder channels and create a tach voltage proportional to RPM. Unless you're electronically savvy, again, not a DIY project as it involves some custom circuit and electronic engineering and access to +/-15v power supplies which the Fanuc should have somewhere in the power cabinet.

However and moreover, getting the scaling factors or polarity matched to what the Fanuc amps want to see may not be that easy - sorry, can't help there. Maybe someone else can help but don't look to Fanuc for much if any DIY assistance.

There was another 4th axis thread posted recently on the 'Zone. In it, I inquired about Haas wiring pinouts for 4th axis rotary table retrofit purposes. In the thread, a link is posted to the site where you can D/L the Haas rotary table user manual. There might be help there for you.

I recall seeing some Fanuc integration info in the PDF, BUT it did require use of the Haas control box and then it only worked as an indexer, not as a true 4th axis, if I recall correctly.

Sadly, you may NOT be able to use the table at all without the "$1000 Haas controller box" nor use it as a true 4th axis in your situation.

If that is not enough, be careful.

Some of the Haas controller boxes drove STEPPERS (as opposed to brushed DC motors) which were used in the non-CNC rotary tables that are driven by the Haas control box. This was told to me by a reputable source but I was not able to verify it with the reasearch I did.

Finally and worst of all, even if Fanuc turns on the 4th axis capability for you on their controller, that doesn't mean that it will ultimately drive the HRT-160 that you bought.

Tread cautiously and do not torch the HRT-160, thus destroying any resale potential that it may have should you NOT be able to get it to work with your machine.

Don't let ANYONE ever say that adapting a 4th axis to a machine is an easy thing to do. Unless the damn thing was BUILT for your machine, the effort can and will turn into a real pain in the frigging A$$ - it has for me....

[hangslot]

Thanks for all the info.

The Fanuc machine is brand new, the Haas a few years old, thats why I want to use the rotary table also on the Fanuc machine.
It will be a big thing to get it to work, so I decided to forget it
As long as the Haas is running in our shop, I don't really need the rotary table on the Fanuc machine, so i bought myself a couple of years. Thanks anyway!!