Cable sizes

Hi,

hopefully someone can help me. I need to know which cable sizes (mm²) are these wires:

Power wire to the duet

wires to the hot end cartridge / fan / thermistor


to extend it for my tall-merod and for dual extruder.


thanks a lot.

I used 7/0.2mm stranded cable to extend my wiring loom. A visual check looked about right (very technical i know), and the spec sheet says its rated up to about 2A per cable which should be enough for a 12V 40W cartridge heater if I remember anything about basic electronics. That is of course doubling up on the heater wires as per the original cable.

So my cables at home with a 0.4mm diameter are ok to use with the motor / hotend / fan for extension the existing cables?

Hi,

any advice for me?

0.4mm is on the low side on what most people would recommend for a 40W heater. That equates to a bit over 3 amps in a 0.125mm² cable.
I don't think any voltage drop over the cable would be a problem (it is a short run of cable, and the hotend heater has plenty of power to do what it needs to) though, the critical point would be the connectors or solder joints. If those have a poor surface area they might get a bit hot, but if they are done right I would not worry too much over 3-4 amps.

The cable to power the whole Duet board though, I would go with as thick a cable as you can fit in the screw terminals. That cable needs to carry a lot more current, and any voltage drops there will have more impact. Mostly it will just make the heated bed heat up slower, but the changes in voltage (which will happen when heaters turn on and off) might have some effect on the Duet in other ways.

Quote
jstck
The cable to power the whole Duet board though, I would go with as thick a cable as you can fit in the screw terminals. That cable needs to carry a lot more current, and any voltage drops there will have more impact. Mostly it will just make the heated bed heat up slower, but the changes in voltage (which will happen when heaters turn on and off) might have some effect on the Duet in other ways.

The loudspeaker cable that RRP supplies for joining the ATX board and Duet 12V terminals is about the thickest you can get into the Duet terminal block. However, that cable has too high a resistance for anything other than a very shorty run. I use this [www.maplin.co.uk] to connect my 12V PSU to the Duet, because it was adequate and readily available to me locally. I terminate it in a 30A 2-way terminal block a few cm outside the Duet enclosure, and use solid core conductors from 30A ring main cable to go from there to the Duet and DuetX4.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Quote
jstck
0.4mm is on the low side on what most people would recommend for a 40W heater. That equates to a bit over 3 amps in a 0.125mm² cable.
I don't think any voltage drop over the cable would be a problem (it is a short run of cable, and the hotend heater has plenty of power to do what it needs to) though, the critical point would be the connectors or solder joints. If those have a poor surface area they might get a bit hot, but if they are done right I would not worry too much over 3-4 amps.

The cable to power the whole Duet board though, I would go with as thick a cable as you can fit in the screw terminals. That cable needs to carry a lot more current, and any voltage drops there will have more impact. Mostly it will just make the heated bed heat up slower, but the changes in voltage (which will happen when heaters turn on and off) might have some effect on the Duet in other ways.

So i will use 0.5mm² cables to enlarge my cables of my tall-merod.

Sorry, I'm not sure of the cable size from memory. I'll check the specification when I'm back in the office on Monday. I pretty sure it's between 20AWG and 24AWG, but then that's between 0.5mm² and 0.2²!

Ian
RepRapPro tech support

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dc42

Quote
jstck
The cable to power the whole Duet board though, I would go with as thick a cable as you can fit in the screw terminals. That cable needs to carry a lot more current, and any voltage drops there will have more impact. Mostly it will just make the heated bed heat up slower, but the changes in voltage (which will happen when heaters turn on and off) might have some effect on the Duet in other ways.

The loudspeaker cable that RRP supplies for joining the ATX board and Duet 12V terminals is about the thickest you can get into the Duet terminal block. However, that cable has too high a resistance for anything other than a very shorty run. I use this [www.maplin.co.uk] to connect my 12V PSU to the Duet, because it was adequate and readily available to me locally. I terminate it in a 30A 2-way terminal block a few cm outside the Duet enclosure, and use solid core conductors from 30A ring main cable to go from there to the Duet and DuetX4.

hi david, hi Ian

at home i have a 2x2,5mm² ofc loutspeaker cable. can i use this to power a duet and duex4 for a dual extruder setup?

2.5mm² loudspeaker cable should do nicely. Only issue is they usually have such fine strands that it might be difficult to get them all inside the screw terminals. Stray strands = dangerous.

Quote
jstck
2.5mm² loudspeaker cable should do nicely. Only issue is they usually have such fine strands that it might be difficult to get them all inside the screw terminals. Stray strands = dangerous.

i will coat it with tin with a solder iron to avoid this.

thanks for the help

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muggi

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jstck
2.5mm² loudspeaker cable should do nicely. Only issue is they usually have such fine strands that it might be difficult to get them all inside the screw terminals. Stray strands = dangerous.

i will coat it with tin with a solder iron to avoid this.

That will help initially, however the solder will flow and the screw terminals will become loose. You will need to re-tighten them regularly until it has settled in.

---

Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Hi,

to build the Y-cable (from power supply to duet and duex4) i will use this:

https://eshop.wago.com/JPBC/0_5StartPage.jsp;jsessionid=C3E455AE1073F1767D4DD952BD746726?zone=6