Am 10.08.2014 20:39, schrieb Pedro Côrte-Real: > > I've now had 3 or 4 DS9490R adapters fail after bad weather. They > seem to be particularly susceptible. After I swap them out the whole > network is fine though. > They have a protective diode against lightning and other EMC inside, so yes, that could make the adaptor fail but at the same time, it protects the network. So if you use another adaptor *without* that diode, chances are high random devices on the network will fail on next lightning strike. The DS9490 is the part where failure is easy to detect and which is most simple to replace.
If you have constant problems with lightning, think about opto-isolating the onewire. There is a pure hardware solution http://home.kpn.nl/thomas_7/1wire/1wire_isolating.html by Thomas Rudolphi and another one featuring an ATtiny13 µC http://sourceforge.net/projects/onewireoptocoupler/ and a small firmware which I have done for my own needs. Opto-Isolating the USB is another possibility, but a bit overkill. http://www.maximintegrated.com/en/app-notes/index.mvp/id/3891 Or use a cheap RS232 opto-isolator and an RS232-Onewire adaptor like the DS9097U or the Link (not LinkUSB). > Does anyone have any ideas on how to protect > them or what good quality replacement USB 1wire masters there are? > The DS9490 is of good quality and there is no real replacement, the other bus masters are mostly limited in speed. Though they may still fit your needs. When it comes to lightning strikes, I don't think any other adaptor will do much better. Maybe it won't fail like the DS9490 but then that means the network will fail in another, unpredictable way. Kind regards Jan ------------------------------------------------------------------------------ _______________________________________________ Owfs-developers mailing list Owfs-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/owfs-developers