Gecko triggered E-stop circuit?

[kong]

You know I thought that 10k res would cause a problem....I havethe circuit soldered up and in place in the wiring box, so I am not gonna take it all apart again for a couple of LED's. I will leave it be for now, perhaps one day in the future if/when it comes out I will go with it. Thanks for the tip though!

[sol]

Hmm... these concerns about the 10K Ohm resistors have prompted me to look over my old build notes to make sure that my schematic is what I built and yup, they are 10K... but the optos held at only 0.3 ma so I left things as they were. Of course the old notes say it worked fine on the breadboard with a 1K as well...but I stuck with the 10K ...was likely a matter of what I had on hand at the time.

Re: Kong and the LED fault indicators... I put a PN 2907 transistor off each opto pin 1 to tiny LEDs so that each LED would be ON when its Gecko was OFF. Used 680 Ohm resistors with the LEDs...ever mindful of the Gecko's 50ma limit since my encoders are powered from the Geckos.

Re: Alexalex, sorry 'bout that, my site was down the week of June 6th ...all's OK now.

[Al_The_Man]

If you go with the series LED's it won't take any more current, especially if the 5v is a high current source, its just that it may be a bit of reverse logic, in other words if they are normally conducting, then the led off indicates an activated condition.
One thing I have found with opto's that are kept normally in the conductive state, the emission appears to degrade over time, so if you are right on the margin to begin with, after time they may appear to fail prematurely.
Al.

[sol]

Thanks for the heads up! Guess it is time to replace some resistors

[WayneHill]

My G320's are wired in series to ERR on all three with a "NO" three way switch to +5 and GND. Is there a potential problem with this setup?

[freak_brain]

ok, call me stupid but I have to ask. What the heck does this circuit do? can someone explain it to me?

I edited this after posting because I decided to read a tad bit more, . I understand what the circuit is for now, thanks



Allen

[snaggletto]

Bringing this thread up again. I'm real interested in building it. However, I have a few questions.

The relay coil shown in the pic is 5V, I've got some 24VDC relays that I use in my Estop system currently. How can I safely modify this circuit to drive a 24VDC coild relay? Thanks for any info.

[sol]

Originally Posted by snaggletto Bringing this thread up again. I'm real interested in building it. However, I have a few questions. The relay coil shown in the pic is 5V, I've got some 24VDC relays that I use in my Estop system currently. How can I safely modify this circuit to drive a 24VDC coild relay? Thanks for any info.

Okay, it is not elegant, but I just use the small relays to control the high current ones.

[jeffery71]

Pulling up an old thread.

I've modified the original circuit some and am wondering if this should work. I tied the geckos together so when one faults they all fault. Then I only have one reset to push to reset all of the drives. I would like to run the relay inline with my limit switches so my control will go into estop when a drive faults.


Jeff T.