Upgrade Fanuc C series drives to alpha series? Anyone know what it takes?

[Garwood]

I'm having issues with a C series Fanuc servo drive. Rebuilt drive is not working well. Lots of bullshit current alarms. Repair outfit will keep working on it or they will just take it back and refund me.

I ran across this article- https://www.mroelectric.com/blog/replacing-servo-amplifiers/

It suggests the C series drives are problematic (Sure seems this way). It says C series can be swapped for alpha series drives.

Interestingly, if I believe what they state in the article, myA06B-6066-H244 C series can be replaced by a A06B-6090-H244 Alpha series and the new and improved Alpha series is actually cheaper.

Does anyone have any experience with this? Especially wrt drive parameters? Does it all carry over, plug and play?

 

[Ox]

But ... wouldn't you need a power supply as well?
Alpha's all have a P/S at the start of the chain.
C's don't.

I'm interested in following along, but in all fairness, I've not had any special issues with C's to date.


---------------

Think Snow Eh!
Ox

 

[Garwood]

Ox, I think they made some Alphas with built in power supplies.

I spent some time on the phone with Fanuc tech support and they say it should work although the tech wasn't very familiar with it.

Then I found this place- https://www.kfasllc.com/A06B-6090-H244.htm

Seems to clear it up. I tried calling them, but no answer. I just sent an email.

I skimmed through the Fanuc b-65192 manual for the 6090 alpha drives and sure enough, it explains that the 6090 series is 100% backwards compatible with the 6066 C series. There's a setup DIP switch on the front that configures the drive to be exactly the same as the C series.

Pricing is roughly $1500-$1700 for a brand new in the box 6090 drive from various sources. That's the same I spent to get a re-famulated 6066 that doesn't work.

 

[Ox]

"Brand new" Alpha for $1600?

Maybe "Brand Rebuilt" more like....
And even THAT is really cheap for no core charge.


------------------

Think Snow Eh!
Ox

 

[Ox]

OK, you are not talking the same "Alpha" series that I am used to.


-------------

Think Snow Eh!
Ox

 

[Garwood]

OK, you are not talking the same "Alpha" series that I am used to.


-------------

Think Snow Eh!
Ox

I know what you mean. My early 2000's era machines use the Alpha's that daisychain on a DC bus. This is not those, but Fanuc calls them Alphas.

My machine is 1995 with a 16T. The servos are Alpha series. The drive is C series. I have all the Fanuc books for the machine and servo drive. The 16T books talk all about Alpha series drives and the C series servo drive book doesn't even mention the Fanuc 16. It's all about the 0 and 15 controls. I think my machine was built at the very end of the brief run the C series drives had. The later drives seem substantially better supported.

And yes, I am speaking of brand new in the Fanuc box drives for that price. Maybe they fell off a truck or something. I don't know.

 

[Ox]

I have C's on a retrofitted lathe with a 16T, and on a Hardinge with an 18AT on it (1994).
I think that I have replaced one on each machine at some point, but not seen a trend any different than anything else.

-------------

Think Snow Eh!
Ox

 

[Garwood]

I have C's on a retrofitted lathe with a 16T, and on a Hardinge with an 18AT on it (1994).
I think that I have replaced one on each machine at some point, but not seen a trend any different than anything else.

-------------

Think Snow Eh!
Ox

Could you tell me if your C series drives use shielded, grounded encoder and motor cables?

The C series drive manual states shielding and grounding is important. However, my Daewoo lathe's cables are not shielded, just a ground wire inside.

This machine has very long history of problems with this drive. Everything else checks out good. Motors, cables, etc. That's why I'm leaning heavily towards the 6090 series upgrade. See if it solves the problems.

 

[Ox]

I opened up a Honda connector, and even there I don't see any evidence of a shield.

Definitely not on the motor leads.


---------------------

Think Snow Eh!
Ox

 

[Garwood]

I opened up a Honda connector, and even there I don't see any evidence of a shield.

Definitely not on the motor leads.


---------------------

Think Snow Eh!
Ox

Thank you very much!

 

[GENERALDISARRAY]

I have used KFAS for repair a few times before. I would use them again. They dont answer the phone though. Email only.

 

[Garwood]

I have used KFAS for repair a few times before. I would use them again. They dont answer the phone though. Email only.

They are on the spot with email though. So far A+ responses from these guys.