Duet3 CAN-FD cable

jens55

The instructions at https://duet3d.dozuki.com/Wiki/CAN_connection make reference to twisted pair cable as well as phone cable. AFAIK, phone cable that is in the flat configuration is not twisted. There is also reference to short cables being not that critical but large printers have to have twisted pairs ... no reference is made to what is short and what is a large printer.
So not wanting to tempt fate and not wanting to chase intermittent communication problems, I would like some more clarity on cabling.
I am building a standard Jubilee printer I will be mounting a tool distribution board next to the tool parking dock. I will have maybe 3 ft of CAN cable going from the Duet3 to the tool distribution board and from there maybe another 3 to 4 ft to the four individual tool boards.
So, can I use flat phone cable for my CAN system or is the overall length too much for non twisted wiring? Do I need to run 2 wires or 4 wires between the tool boards and the tool distribution board?

Alex.cr

@jens55

My experience is as follows. 1-3 ft wires are fine to use with good quality phone cabling.

It is noise from steppers that has been my issue.
Anything that travels next to stepper wiring needs to be a twisted pair (or shielded) and separated by at least 1/4 inch from the stepper motors.

In your case I would think the phone cable would be fine as long as no stepper or any other major noise source(mains bed wiring to name one) is around that wire.

deckingman

@jens55 the advice I received from @dc42 was to use High Speed ADSL2 cables - specifically the ADSL2+ listed here https://www.kenable.co.uk/en/107-adsl-rj11-cables Available in black or white and from 0.5 metres up to 15 metres.

jens55

@deckingman. Kenable doesn't seem to ship to Canada.

jens55

@alex-cr, thank you, that helps.

deckingman

@jens55 said in Duet3 CAN-FD cable:

@deckingman. Kenable doesn't seem to ship to Canada.

Well that's another 5 minutes of my life that I've wasted and won't get back.

I didn't for minute expect that Kenable would ship to Canada. I was pointing out the spec that DC recommended - i.e. ADSL2. I doubt it matters much who's make ADSL2 you use.

I'm completely blown away by the appreciation you show when I take the trouble and spend time trying to help you. The gushing thanks is really not necessary.

jens55

@deckingman, Oh come on .... be nice .....
I did mention the link to the page where @dc42 specifically links to Kenable and provides the 'sort-of' specs so it wasn't a case of "hey, isn't that great, I can get my cables from here, thanks a million Ian, I couldn't have survived the day without that information". I was looking for more relatable 'specs' rather than the somewhat imprecise use of 'big printer' and 'small printer'.
I did go to Kenable, made an account and tried to order cables but didn't get past the shipping issue. I probably wasted just as much time that I won't get back .....
At least I did acknowledge your post rather than not replying to it.

Oh, I don't know if you remember or not but not too long ago I supported you in your discussion on the forum about weird Duet3 issues you had and that was probably more than 5 minutes of my life that I gave to you ..... so let's be nice and civilized.

If you like, I will gush all over the place about the help you have been in the past if that makes you feel more appreciated.

Lastly, neither one of us is here to count every minute of help received or given. It's supposed to be a forum for exchange of ideas and help.