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Fried Control Board


I have a Benchman XT CNC that has a fried controller card. The replacement card they quoted me was 10,000 so that will not happen. I need to know how do I go about switching to a USB controller card, breakout card or other controller. I see many available but do not know what I need, and what I need to do. The machine did work great before the power surge and I would like to get it up and running. Any help would be great.


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Easy stuff first;

  1. Have you checked the power supplies that go to the controller board?
  2. Do you know any technical information on the controller board? Such as, is it opto-isolated.
  3. Does it have any leds that are normally on which are now off?
  4. Does Benchman have an exchange program where they will repair the controller board?
  5. Sorry I can’t get out of this numbering mode. A seasoned electronic technician may be able to repair the controller board. At $10K it may be worth your time to seek out a technician. Often a technician can look at a board and check some of the more obvious parts for defect. Since you have information on how it met it’s end, that is a clue on where to initially investigate. Without the controllers technical data and experience working on the controller a technician will be disadvantaged but can often find at least some of the damaged parts. You may get lucky. I am assuming the board is not literally burnt. Some electronic parts such as fuses are very small and difficult to identify but would be obvious to a trained eye. You may be able to take a very close look at the board for any labeling like F1, F2, 5V etc and with a multimeter check continuity of fuses (not all fuses are glass tube that pull out) and voltage that feeds the controller board.
  6. If you can get a tech over to the location of the machine these simple checks can be made on site and offers a good possibility for troubleshooting. All the power supplies and communications control cable from the computer to the controller board are there. Testing the board without technical data and experience on the controller is much more difficult when removed from the machine because one cannot duplicate the operating conditions for the board.
  7. Good luck I hope you can find a seasoned journeyman in you vicinity to at least take a cursory look. I can tell you from experience optisolators are one of the higher failure rate items as are fuses.
  • Little Chips answered 2 years ago
  • last edited 2 years ago
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Back in another life, I designed all of the electronics for Light Machines/Intelletek Benchman, Prolight, and Spectralight machines.

The I/O IS  opto-isolated. The electronics are  of a simple, robust design, and are usually very reliable.

There are a lot of those machines out there, and if Intellitek is not supporting them, maybe I should hang out my shingle!

  • Light Machines EE answered 1 year ago
  • last edited 1 year ago
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If the controller card you are talking about is the one in the electronics enclosure on the machine, it should be a relatively easy fix. There are schematics available if you just search the web. If it is the controller card in the PC then you are stuck trying to find one on ebay etc. There were two flavors of PC controller cards, both by baldor/nextmove. There is an ISA version for the older PC ISA bus and there is the PCI version for the newer PCI bus. (newer/older being relative terms now in 2017). I see cards on ebay every now and then for ~$2K.

  • Donald D Hughes answered 5 months ago
  • last edited 5 months ago
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