[TR MFG]

I am researching the purchase of another machining center for our company, it will most likely be a used machine. I would like to know what the differences are between some of the Fanuc controls. We are looking at mid to late ‘90’s machines and see 15M, 18M, 21M, OM, OMD, OMC and some have “I” added on to the name. I know all this must mean something? We have been using machines with 6M-B controls and the only thing that we felt was missing from these was DNC, we added BTR cables to them and they work fine for us, other than being slow on the 3D stuff. The 6Ms we have, have G54-G59 and some other options turned on. If anyone can clear up what the difference is between these models it would be appreciated.

[Dan Fritz]

All of the controls you mentioned are newer than your 6M-B controls.

The Fanuc 6M and 3M (and the rare 9M) were developed at about the same time, and the system 3 was designed to be a less expensive version of the 6. All three had 16-bit 8086 processors. The 6M had bubble memory and lots of available options. As you know, there was a 6M-A, a 6M-B, and later a "level up" version called 6MB-2. The Fanuc 3M used SRAM memory (which was limited) and had no tape reader port. You can connect a BTR board or cable to the 6, but you can't do that with a system 3 because there's no parallel tape reader port. The 9M was seldom imported into the US, and it had the ability to control up to 15 axes. The 6M could only handle 4 axes simultaneously.

The next generation of controls that Fanuc produced were the system 10, 11, 12, and 15 controls. The 10 (like the 3) was a good control, but it was much more limited than the 11, 12, and 15. The 10M used SRAM memory likt the 3M, and it had no parallel tape reader port. Some 10M controls, however, could DNC through the serial port. You've got to be careful when buying a 10M for DNC operation, because a lot of machines builders used the Fanuc 3M, then switched to the 10M without changing their PC Ladder. These machines can't use the serial port for DNC unless you do a bit of work on the ladder.

The 11M control used bubble memory (like the 6M), and it had a parallel port, it could DNC through the serial port, and it had all the options you would normally need on a machining center. The processor speed was the same as the 10M though. The 12M is also rare (like the 9M), and I really don't know much about it. I suppose it had the ability to handle more axes than the 11M.

The 15M was the most powerful control in this generation. It had all the "bells & whistles", and it could be equipped with options for high-speed cutting, remote buffers for faster DNC, etc. Like the 11M, it could DNC through the serial or the parallel port.

The 0 series controls came out next, with several generations of hardware. The 0M-A could not DNC at all (no parallel port, and the serial port could only upload/download). The 0M-B had an additional interface bit (accessible by the ladder logic) for DNC operation. If the machine's ladder has this function, you CAN do DNC through the 0M-B and 0M-C serial ports. On these machines, look for a "TAPE" mode postion on the mode select switch. If the mode switch only has "AUTO" and "EDIT", then you may not have any DNC capability unless you modify the ladder (like some older 10Ms) None of the 0 series controls had the parallel tape reader port, so no BTR boards can be used.

The next generation of controls were the 16, 18, and 21 models. These all had faster processors than the 0 series, but they too had some limitations. These are currently the most popular Fanuc controls being sold, and they have all the options available. DNC is possible on all models as long as the machine tool builder put the "TAPE" mode on the mode select switch. High-speed cutting and remote buffer options are available, but not all controls have them installed. These controls also have only serial ports (Not parallel ports) so BTR boards can't be used. Most models also have a PCMCIA RAM card slot next to the CRT. You can run long files from this card if you set the "I/O" bit on the setting screen to "4"

The "i" models have a kind of "front-end" processor that makes Ethernet communications possible. If the control has the "Data Server" option, you can use an FTP server on your PC to transfer (and drip-feed) files at Ethernet speeds. Just because the control is an "i" model doesn't mean that you have these options though.

With each generation of controls, Fanuc has offered a "low end" version with limited memory for simple machines, then an "intermediate" version for the vast majority of standard machines. They've also always offered a "high-end" control for big machines with many axes, parallel axes, and other special requirements.

When buying any used machine, try to get the original Fanuc documentation from inside the cabinet. It should show the factory installed options. Also be VERY sure to get a set of all the manuals. You will need them. If the machine is under power, just try to use MDI to key in the various optional G-codes. If the control gives an alarm #10, that means that the option is not installed.

The Fanuc model numbers never include the number "13" (unlucky here in the US) and the number "4" (unlucky in Japan). That's why there wasn't a model "4" or a "14" or a "13".

[TR MFG]

Dan,
Thank you this is the information I was looking for. Can all of these do a XYZ helix if the option is turned on?

[Dan Fritz]

Yes, I'm pretty sure that all these Fanuc models have helical interpolation as an option. You will find that some machines don't have the option turned on. The only way to find out for sure is to try to execute a helical move (and see if all 3 axes really do move), or refer to the manufacturer's option list.

[TR MFG]

thanks again Dan, we actually have your software to BTR cable feed our 6m controls. It works AWESOME!

[Dan Fritz]

Gosh, thanks. I'm glad you like it.

[soren60]

Very intresting info Dan.
Do you have similar info on older systems?
I have a 4-axis Niigata HM50 with 7M from 1979.
Is 7M older than 3000C ?

[Dan Fritz]

No, the 7M is newer than the 3000C. The 7M wasn't very popular here in the US, but it's about the same generation as the Fanuc 6M and 3M. The 2000C (for lathes) and the 3000C (for mills) was older, and did not have a microprocessor. Instead, it had a CPU made of descrete components.

Here's the approximate order of Fanuc models that I can remember (oldest to newest):

20A, B, and C (pulse motors, descrete CPU - no microprocessor)
200 A, B, and C (magnetic core memory, descrete CPU) Used for EDMs and punch presses
2000C, 3000C (DC servos with resolvers/inductosyn scales, descrete CPU)
5T, 5M (8-bit Microprocessor + CMOS memory, DC servos with pulse coders)
(these controls came out at about the same time):
3T, 3M (16-bit Microprocessor + CMOS memory, DC servos with pulse coders)
6T, 6M (16-bit Microprocessor + magnetic bubble memory +pulse coders or resolvers/inductosyn)
7M (16 bit microprocessor, DC servos with pulse coders)
9M (16 bit microprocessor, bubble memory, more axes than the 6M)
10T, 10M (32 bit processor, CMOS memory)
11T, 11M (32 bit processor, bubble memory)
12M (32 bit processor, bubble memory, lots of axes)
15T, 15M (32 bit processor, bubble memory, lots of axes + bells & whistles)
0T, 0M (lower cost control, CMOS memory, very popular)
16, 18, 21 series
16i, 18i, 21i series
(all the current models)

[Jung]

Good info for me, Dan Fritz.
By the way, when you mentioned ladder, can you tell me about Fanuc Ladder II software: what can it do? and Which device do we need to use this soft?
Thanks

[soren60]

Thank you Dan for the info.
I think 7M must be older than 6M, it programs whit trailing zeros,'
and have no screen and have resolver feedback. But it is full 4-axis control.
Some dealer here in Sweden say it is the same system as
Siemens 7M.

[Jung]

Hi DanFritz,
Do you think a Fanuc 3M/3T system can use DNC through RS232 port?
I just saw a 3M machine, that can be DNC. On the past, I had thought Fanuc 3 system could not have DNC capability.
I cannot take a look inside the cabinet so I dont know how it works.
Do you have any idea?
Thanks

[Dan Fritz]

Jung: The Fanuc 3T and 3M never had a TAPE mode, so DNC operation was impossible. All you could do is load a program into the limited memory and run from there. The serial port can only be used to upload/download programs in EDIT mode.

I've heard that somebody has modified the original 3M firmware (EPROMS) to permit TAPE mode operation. I've never seen it done, but check with Memex or Tulip Technologies for info on this.