Steve Etter
Lifetime Supporting Member + Moderator
Hi all,
This is way off topic, I know, and I hope y'all don't mind too much, but since it is communications related I thought it might be Ok.
I recently "fried" a CNC machine (~$9,000 worth of repair) when I replaced a UPS on a peripheral PC that is used to store parts programs. This PC is connected to the CNC via an RS232 cable and there is a small application that runs on the PC to suck the parts programs from the CNC and store them on the harddrive and then to poke them back into the CNC when needed.
Talking to the tech support guys from the CNC manufacturer, I am told that the serial cable between the two should remain disconnected whenever uploading or downloading is not happening. Had this been the case when I attached the new UPS, they say, the problem would not have happened (Yeah, right). The reason for keeping the cable disconnected, they say, is to protect against the effects of lightning, etc.
Anyway, this is a plant-floor machine. The PC is right there, on the plant floor, at the machine. The guy who uses it is the machine operator and he needs it when he needs it. What he doesn't need is to have to attach and disconnect the cable every time he uses it. I have no doubt that the cable will remain attached eventually.
Ok, finally...my question: Does anyone know of some kind of filter/buffer that goes inline with serial cables to protect against spikes and such caused by lightning, etc.? As far as liability is concerned, I am pretty sure the CNC manufacturer will not recognize anything short of their recommended procedure, but I cannot live with this procedure, either. I need to find some sort of reasonable way to realistically reduce the machines exposure and keep the cable attached at both ends.
Thanks,
Steve
This is way off topic, I know, and I hope y'all don't mind too much, but since it is communications related I thought it might be Ok.
I recently "fried" a CNC machine (~$9,000 worth of repair) when I replaced a UPS on a peripheral PC that is used to store parts programs. This PC is connected to the CNC via an RS232 cable and there is a small application that runs on the PC to suck the parts programs from the CNC and store them on the harddrive and then to poke them back into the CNC when needed.
Talking to the tech support guys from the CNC manufacturer, I am told that the serial cable between the two should remain disconnected whenever uploading or downloading is not happening. Had this been the case when I attached the new UPS, they say, the problem would not have happened (Yeah, right). The reason for keeping the cable disconnected, they say, is to protect against the effects of lightning, etc.
Anyway, this is a plant-floor machine. The PC is right there, on the plant floor, at the machine. The guy who uses it is the machine operator and he needs it when he needs it. What he doesn't need is to have to attach and disconnect the cable every time he uses it. I have no doubt that the cable will remain attached eventually.
Ok, finally...my question: Does anyone know of some kind of filter/buffer that goes inline with serial cables to protect against spikes and such caused by lightning, etc.? As far as liability is concerned, I am pretty sure the CNC manufacturer will not recognize anything short of their recommended procedure, but I cannot live with this procedure, either. I need to find some sort of reasonable way to realistically reduce the machines exposure and keep the cable attached at both ends.
Thanks,
Steve