Losing Communication

[jkaras2000]

Hey Everyone: Very interesting posts. I think I would like to try a USB ISOLATOR. Can anyone suggest a brand/model that they have had good success with. Also, would I need two USB ISOLATORS, one per each usb wire coming out of control box? I may also download and try the Beta version to see if there is an improvement. Happy & Healthy New Year To All. Joe.

[dana_swift]

Joe- as near as I can tell the devices are fairly generic. Although there must be some tiny difference between units, try an inexpensive one. I have not tried this brand, but its probably as good as any:

http://www.amazon.com/Multi-purpose-...s=usb+isolator

Its under $40 plus shipping.

The primary value of an isolator is to break ground loops. If that isn't a problem you are having they don't help. There "might" be some value in dust collection static interference with USB. The isolator should not introduce any new problems if it doesn't help. There are no drivers or anything. To the system it just appears as "cable".

Which USB lines need them? The ones that are part of a ground loop. What the isolator does is break the connection and stop circulating ground currents. How do you determine which ones those are? Either a clamp on ammeter which reads currents under about 10 amps full scale. If you have ground loops it will be showing current in the ground and usb cables that conceptually has none. A second method is to check for differential ground voltages. If current is flowing in ground wires, the resistance of the wires generates a voltage which can be measured with a plain-jane ac voltmeter. If you are seeing a difference in ground voltage from one point in a ground system to another when the equipment is running over about 50 milli volts, you have clear evidence of a ground loop. By 500mv you have enough ground differential to mess up USB.

I am accused of providing too much information. I will stop there-

Let us know what your experience is!

D

[Joe Porter]

Dana, your responses provide more help than you can imagine. Please keep it up. I am working up to the day when I feel like I can ask an intelligent question. Thanks....joe

[jkaras2000]

Thanks for the thorough response Dana: I don't mind reading a lengthy response at all. I appreciate your covering all the bases. I will check out the USB Isolator Link you posted. Before I ran a copper line through my air vac hose, I used to get fouled up with Lost Comm Messages fairly often. After adding the copper wire, it was like night and day. One day not too long ago, I was running the bot, and had a few Lost Comm's within a three hour time period. (Very Frustrating) I decided to sleep on it and get a fresh start in the morning. Low and behold it cleared up, and in fact the Bot is cutting as I type. Don't know what was up. I have also wrapped a copper wire on the outside of vac hose and is grounded to vac along with inside wire. The notion of the USB Isolator just seemed like a simple thing to do to help insure less or even no Lost Comm's while running a file. Joe