Can somebody help with details on converting from 480 to 208 volt input power?

4 things are necessary.
Change motor windings to 220. The way to do this is on the motor plate. Just follow the "low volts" schematic.
Change spindle motor overload.
Change the main fuses to what is specified.
Retap main transformer per wiring diagram to 208, there is a table on the wiring diagram as to where to put lines in and jumpers.

George

Re: changing spindle overload

You have to change the entire breaker. EMI has them. You can run a 440 breaker on 208 (we did it for 2 years) BUT you'll trip due to much higher current...

You'll get away with that for a while until you fry the breaker sense circuit 1 too many times. At that point, you WILL have to replace/change the breaker.

For those uncertain, it might not be a bad idea to unplug the compter power supply (P/S) and check the control power voltage on the PC side of the P/S before you simply try to run in real time mode.

Thanks for the helpful tips.

I have tried to get a manual for this machine from Bridgeport and they are out of print. Any ideas on where to source the maintenance manual or even a copy of the schematic that shows the transformer connections?

Many different schematic exist. The fact that it is a DX narrows it down to:
Cutler Hammer Control?
Computer Express Control?
Or plain open mother board oldest DX32 control?
BTW, 2 or 3 axis?

George

The machine is a EZ-Trak DX2/3. Any suggestion on where to find the schematic or just a print for the transformer?

thx
jon

Attached is a PDF of an EZTRAK DX wiring schematic.

George

I will try attaching again.

George

The drawing posted by MACHINTEK is that of what I call an "early" machine. The drawing has been replace by DWG No. 94-33690 Rev AQ.

The AQ is basically the same drawing as the PDF but it has been updated to show the 12749250 and the 12398993 3rd axis option configurations. It shows the transformer connnections for various voltages and more info on the computer and "flash drive" settings.

The 31542518 breaker that needs to be changed when rewiring to 208-220 can be obtained from EMI cheaper than a comparable one from Grainger.

FYI: The '993 option has an encoder on the Z axis along with the DRO scale for true feed back (two mil spec connectors ala X 7 Y axis). THe '250 Option merely has the DRO on the 3rd axis and NO encoder thus only 1 MIL connector.

However, the schematic is adequate for addressing the original wiring question posed by SWIMJAM66.

Actually, that was not an OPTION. Bridgeport found out that the linear scale on the Z (quill) could mis-read under heavy milling. This would cause the Z axis to try and correct its position. Not good.
Bridgeport issued a recall/upgrade in which the Z motor was replaced with one that included a rotary encoder at the end of the motor. Of course this involved a lot of work to rewire the machine, etc. The dealers were reimbursed for a bout an hours work and of course this took the better part of a day including driving. Therefore I do not know how diligent the dealers were about doing this.
The question is simple, do you have 2 or 3 cables coming off your Z motor?
Given the correct configuration of the machine, a matching schematic can be found.

My office had a habit of "selling ice to Eskimos". They would sell a three axis conversion for a SX machine. This involved the mounting of an additional cabinet for the 3rd axis drive and the hard drive. This bit them in the rear later when the upgrade kit came out and the original BMDC did not support an additional axis encoder input.

George

George

Our EZTRAK is single wire Z axis servo with Accu-Rite DRO scale and the outrigger arm drive spindle - it was purchased as 3 axis and (surprise) we never got any retrofit offer for the Z which we surely could use now!!!. Expecially since we're G code moving the axis and we're psuedo profile milling and feedback sucks on Z for reasons you cited.

In researching the system for to fix a gremlin elsewhere, some service people sent us the schematics for the AUXBOB and AXSBOB cards and pinouts for the BMDC card. SOme interesting observations.

All three items mentioned were configured for 4 axis plus spindle speed control. They simply didn't stuff the cards fully with the parts needed or didn't install the proper proms needed to make the BMDC in 'TRAK talk like it was envisioned.

Essentially, the EZTRAK was hard and software throttled so it could not do 3 & 4 axis ala properly. The chips and hard logic were there as they supposedly used/were planning to use the BMDC card on low and high end machines with some or all of the features.

Alas, BPT went under and development ceased. Some of the stuff was supposedly included in ver 7 of the O/S but it was buggy and never officially released. Oh, what could have easily been 10 years ago that Hardinge/BPT is just now trying to exploit..... Go figure.

Thanks for all the help. I will compare the emailed schematic and then determine what type of controller it is.

Jon

The original BMDCs were socketed chip carriers and yes, they saved money by configuring a board for the application. I have a cheat sheet of all the part numbers, clock speeds, and configurations.
There was even a BMDC4.
My apology, I meant to say 1 cable or 2. 1 cable was power and tach only. The 2nd cable was for the encoder.
The newer motor used the linear scale when in 2 axis mode and the rotary Z encoder when in 3 axis mode.
I believe you are sucking big wind with your older 3 axis stye machine. I know of many shops that have thrown that away and purchsed the newer style with the Z ballscrew right in front of the quill housing. Still limited to drilling with a 3/8 drill in mild steel.


George

Here is my BMDC cheat sheet.

George

Could someone please post these - having trouble working out where the bug is in getting my BPT EZTrak SX (ugraded to DX2) running.

Thanks.

Please give symptoms.
The first difference between a SX and a DX was a better mother board and a hard drive. Some of the older SX machines did not like newer software. I usually draw the line on the older machines with ver 3.02.

George

I found the problem - the mother board on my machine died and I replaced it with one from a old compaq presario computer I had in the attic. Apparently I didn't push the 50 pin cable from the AUXBOB board to the BMDC on all the way - guess I qualify for tri-focals now. Thanks anyway. Machine seems to work fine but I think the software version I have may be from the older SX model - the screens don't match the ones in the programmers manual I have (manual is labled DX-32). Is there any place I can down load either an SX programers manual or DX-32 software?

The EZtrak software had a BMDC.bin file that loaded to the BMDC. Typically for newer software a newer BMDC is necessary to have the chips to run the newer bells and whistles. Every version of software was a little bit different with items moving around on a page or to a different page. Some canned functions may have more choices, etc so there is no book that will precisely fit a piece of software.
I do not know where you can download EZTRAK software as most wirewalls now look inside .zip files and stop all the executables. I have almost every version Bridgeport put out but stopped emailing them to my service techs as it never come out OK at the other end. Example (before firewalls), I would email a disk. It was zipped by AOL and when unzipped, it filled 3 floppys as all the files unzipped including the ones that were supposed to stay zipped on the install disk. I worked around this by sending my techs a diskcloner software. I could create an image, email it and they could create an exact copy of the original disk using that piece of software.
The OS also went through a evolution. Bridgeport settled on DOS 6.20 and the later versions were based on this version.
What is the part number of your BMDC? What version of DOS and trak software are you using?

George

The board has printed on it:
BMDC2
FAB1942937
ASM1942938

It also has stamped in black ink 1942967

The DOS version is 6.2

I think the BPT software version is 6.00 but it flies by so fast I didn't get to confirm that (shut down re-started twice to read it). If you need it closer than 6.0X, I can try again.

Hope I have the numbers you need posted here.

Thanks for your help.

Something to watch out for on motherboard changes:

We, too, installed a new M/B in our EZTRAK. We didn't know that the 'Trak software was NOT able to deal with LBA (large block access) capabilities found on newer M/B's. This feature is optionally set in the BIOS.

Result: the computer would put stuff on the hard drive that the 'Trak software couldn't find. This led to repeatability and all sorts of other irritating problems. You also need to set the BIOS to write the cache before exiting. This too causes problems with X=0 and Y=0 and Z=0 resets not being saved if you do NOT write the cache before shutting down.

We learned that the 'Trak software was written when hard drives were small and capabilities limited for DOS. Thus, you can't get too fancy when you try to use newer M/B's and all the other features of DOS. We also learned that you also can't load a huge aftermarket drive and expect the software to be able to use/access all of it.

We even tried to load Dosshell and run the 'Trak software out of 'shell - this being done to enable easier file maintenance. Don't even try to do that!!!!. :eek:

If you simply load and run the 'Trak sofware as-is, the thing will run fine. You can load Dosshell or other programs for disk maintenance (IE: Xtree, etc) but you have to exit from 'Trak via the utilities screen, do your thing with these program and then restart trak (we simply execute AUTOEXEC.bat from a C:\ screen or via dosshell.

Hint: install a DOM (disk on module) instead of a hard drive. Much more robust and dare I say convenient than a hard drive. Contact BPT Machine in Carol Streak IL for one (I am not affiliated in any with with BPT - he did a service trip to me and I had to pay just like the next guy).

After doing so, our machine runs like a champ :o whareas we were ready to can it or use it as merely a drill press...