Troubleshooting a Gecko

[waynec]

I have an older shopbot that I've upgraded to the Ascension 1000 controller. I'm having an intermittent problem with one of the X motors not working.

When I switch with another G202 in the Ascension box the motor starts working. This leads me to believe that cabling and such are OK, and that the Gecko G202 is likely bad.

Is there a way to confirm this other than swapping G202s in the Ascension? The G202 looks physically OK, no funny smells, no escaped smoke, nothing that tells me its fried.

Argghh. What is the fastest repair? A new G202?

Thanks for input from anyone with experience with bad Gecko drivers.

Wayne from White Salmon
waynec@gotsky.com

[gary_n]

I have had the same problem, the Z driver. At fist I thought it was heat, and added an add'l 4 3/4 X 4 3/4 fan, blowing right on all the drivers. I'm sure that helped, but did not solve the problem. My Z driver quit would and after changing channels with the Y driver, both Y & Z would work. This went on for a few days. We had some pretty high temps. at the time. I finally wound up ordering another gecko 202 driver. It is due tomorrow.

[cnc_works]

Wayne, I have an Ascension box and had exactly the same problem. The off side X driver would intermittently quit, usually on long rapids. It would continue working after recycling the box. I replaced it and have had no problems since (a year and a half or so).

Donn

[weslambe]

I've had problems with my 202's on my home built machine since the day I got it running. That's been almost a year.

I've sent the Gecko 202's back for inspection and each time they come back as testing good.

My problem was that my x drives would quit intermittently. Cycling power on the control box would start the drive again for some period of time.

A friend sent me a couple of 201s since he has a good idea that the 202 has issues. I replaced the 202s on the x axis with the two 201s and then ran a sign job. The job ran for 59 minutes then the Y axis failed for only the second time in a year.

I am getting a whole new control box on loan to try it out.

I've also been talking with another shopbotter who is having problems with his 202's. He is of the opinion that Mach is causing the problem.

Check out www.warp9td.com This is a link to a company making a pulse controller that works between mach and the controller bypassing windows.

I think there are lots of people having problems with these drives

[richards]

Contact Shopbot and ask about their V201 controller card. It allows you to use SB3 software with the controller of your choice.

If used with Gecko G201 or G202 stepper drivers, you would only have to invert the step and pulse signals with a 7404 chip (or something similar). The V201 card can drive the Gecko G203v stepper drivers directly.

I've been using the card for several months and it has handled everything that I've thrown at it.

[bill.young]

Hi all,

For you tinkerers that want to find out more about the V201 controller card, we've put some information in a wiki at http://shopbotdev.pbwiki.com/

Wikis are always a work in progress but Mike Richards has done a great job of supplying content to get it started...many thanks to him.

Bill

[gskinner]

Did not know Shopbot had a controller they sold separate from there systems.
Can someone give me an idea of what the V201 controller costs?
Those of you that have used Shopbot software and Mach software what one do you prefer?

[richards]

I run Shopbot software on my PRT-Alpha and on the V201 controller board at the test bench. I run Mach3 software on several other test setups.

Without a doubt, the Shopbot software is easier to use. The SB3 software easily handles Input and Output instructions so that you can control various attachments to your machine. The SB3 programming language is more like other programming languages so that you can call another cut file from within a cut file. You can use labels and GOSUB routines for peck drilling, circular pocket drilling and all other specialized tool paths.

On the other hand, Mach 3 has the ability to cut an arc with the Z-axis being one of the active axes. However, to get some of the features that are built into SB3 with Mach3 I've had to resort to writing a custom code generator. It's not difficult, but without programming experience, it's not something that everyone would feel comfortable doing. Very simple operations like turning a spindle on via software and detecting a Zzero plate are more complex with Mach3 than with SB3.

If you're familiar with computer languages, SB3 is more like BASIC and Mach3 is more like Assembler Language.

As for the cost of the V201 board, give Shopbot a call. Ted Hall and I talked about pricing at the Maker Faire in California earlier this year, but I don't know what the final figures are.

[weslambe]

I just replaced all of my 202s with 201s. My machine hasn't had a fault using the 201's yet but I am still doing air cuts to be sure. I am a couple of hours into the air cuts. Using the 202's I would have faulted in about 20-30 minutes max.

[richards]

The Gecko G202 is an upgraded version of the G201. The G201 is an older design. Every designer that I've talked to chooses to use either the G202 or (more likely) the G203v.

The G202 shuts itself off if it gets too hot. There is no LED to notify the user that the G202 had overheated, so some people would assume that the stepper driver was flaky when it was just doing exactly what it had been designed to do. The only way to reset a faulted G202 is to turn the power off and then on again. However, the real solution is to mount the G202 on an adequate heat sink so that it doesn't overheat.

I've been running four G202 stepper drivers for over two years under the most harsh conditions imaginable. Those four steppers are mounted on a $20 strip of aluminum that is 3/4-inch thick. The G202s have never faulted on me.

I've had similar success with the G203v stepper drivers; however, I have them mounted on a 1/2-inch thick piece of aluminum and they have never faulted on me either. The G203v has the added feature of an error LED so that you would know if the G203v needed to go through a power cycle.

The only problems that I have ever had with any of the Gecko stepper drivers and the Oriental Motor stepper motors has been bad connections. I've been careless a few times and screwed the terminal down onto the insulation on a wire instead of on bare wire. A quick continuity check with a meter has always found that problem. That, of course, was totally my fault.