EZ Trak DX2 Voltage Conversion

[swimjam66]

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

[machintek]

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

[NC Cams]

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.

[swimjam66]

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?

[machintek]

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

[swimjam66]

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

[machintek]

Attached is a PDF of an EZTRAK DX wiring schematic.

George

[machintek]

I will try attaching again.

George

[NC Cams]

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.

[machintek]

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

[NC Cams]

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.

[swimjam66]

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

Jon