Disandavantages from 12V

SupraGuy

I've had some bad luck with 24V supplies, so I've considered putting 12V everything back into my printer.

The 12V hotend heaters tend to be lower wattage as well. Most of them seem to be about 30-35W, whereas most of the 24V ones are 40-50W. This seems to affect warm-up time more than usability.

Heated beds at 12V tend to be much lower wattage as well, but if you're going to use mains power and a solid state relay, that shouldn't be a problem. (Personally, mains power for a heated bed makes me nervous.)

If you are running multiple motors for an axis, 12V can have some issues pushing more current. It might be okay if you can move them to different drivers.

There are some advantages to 12V. Fans are cheaper and more reliable. Many other accessories are 12V tolerant, but not 24V tolerant. High wattage power supplies are readily available, with high reliability.

genghisnico13

High inductance motors are noisy at 12V in spreadcycle and you start to loose torque at high speeds sooner than at 24V.

kolja

As already mentioned less torque from motors. On the other hand try to get your hands on 24V fans... With 12 you could just go and buy whatever is out there - eg. superquiet Noctua-fans.

briskspirit

@kolja Why not to use 5V output for fans? Imho it is not a problem.

dragonn

@kolja said in Disandavantages from 12V:

As already mentioned less torque from motors. On the other hand try to get your hands on 24V fans... With 12 you could just go and buy whatever is out there - eg. superquiet Noctua-fans.

Just add a 12V step down for fans, you can easy connected it to duet V_FAN pin and have all fans running from 12V with a 24V supply.

kolja

@briskspirit hell! yes - you're right. my printer came with 24. will have to check that.

kolja

@dragonn i thought to go down this road.

Knaudler

I'm running my CR-10 with Duet Wifi - with 15V
works good - fast heating
12v Fans working - using 80-90% pwm

Phaedrux

https://duet3d.dozuki.com/Wiki/Choosing_the_power_supply
https://duet3d.dozuki.com/Wiki/Choosing_a_bed_heater
https://duet3d.dozuki.com/Wiki/Choosing_and_connecting_stepper_motors

Some relevant topics discussing how 24v affects each.

mrehorstdmd

I use these to run fans, LEDs, etc. in my 24V powered printer. They seem to be reliable and they run cool. They're tiny and cheap!

Danal

Not so much "showstopper" disadvantages for 12V, it is just that 24V is better at, well, everything but fans. And 5V is one jumper away for that...

dc42

12V is adequate for small Cartesian printers. The advantages of 24V are:

Easier to heat a large bed than 12V, because you get double the power for the same heater current
Higher maximum speed, which can be useful for travel moves on deltas and on large printers
The possibility to implement resume-after-power-fail.

briskspirit

@dc42 How to choose threshold voltage for resume-after-power-fail ? Thanks

Jacotheron

I selected 22V as the threshold, and 23V as the restore. My PSU provides stable voltage (never dropping below 23.9V and never going over 24.5V).