48 volt steppers board selection

deckingman

@luke-slaboratory I understand what you are trying to say but I don't think you've made a convincing case for using 48V. My point is that I use 1500mm/sec^2 with 3Kg + of moving mass but that's still well within the torque capability of those 2.8Amp motors (running at 2.3A) even at 24V. If I had a "sensible" hot end which weighed say 300 gms instead of 3Kgs, then I could use 15,000 mm/sec or more for the same torque. That's still less than half the 6 + Amps that the Duet board is capable of. I guess we'll just have to agree to differ.

rexx

@deckingman sorry for the super late reply life been a round latley but i am back in and read the posts and if you are correct i should be ok with only a duet 2 not Duet 3 hc6 but (duet 2) as you said only 2.3 A actual @ 24VDC i have the 178 oz 1.8 deg i forget the MH resistances but i would love to use the duet 2 instead of 3 i think ???..

the duet 2 is rated to 2.8A-firmware set to 2.4A do you think i could use this under your limits above?

i am only driving 3 nema 23x57mm and 2 pankcake nema 17's at 24VDC the duet 2 does goto 32 VDC
feature wise the duet 2 is fine less the close peek amps.

rexx

@deckingman Also i dont need 5 amps way over kill your correct i have 2.8 amps nema 23 (x3) can i try a duet 2 in your opinion or go for the 3 ?

rexx

@deckingman the nema 23's are 23HS22-2804S MH2.6 @1KHz inductance with .9 Ohms resistance @25C 1.8 deg rotor inertia 300 g-cm2
on duet 2 or 3 6hc?

deckingman

@rexx said in 48 volt steppers board selection:

@deckingman Also i dont need 5 amps way over kill your correct i have 2.8 amps nema 23 (x3) can i try a duet 2 in your opinion or go for the 3 ?

IMO, either generation will drive those motors. So the choice comes down to other features you might want and the price you want to pay. Check the specks of each board but ultimately the decision has to be yours. One minor consideration is that later generation products are likely to be supported for longer than earlier generation products but AFAIK, Duet are not planning on dropping support for gen2 any time soon.

jay_s_uk

there will be features that don't make it to gen 2 boards going forwards though, such as multiple gcode streams

A Former User

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jay_s_uk

if 48v is really required, I can see 6 options

Use a duet 2 with an external breakout board, allowing external drivers to be used at higher voltages
Use a duet 3 6HC/mini+ with 1HCL boards to run at 48v
Use a duet 3 6HC/mini+ with 1XD boards to external drivers to be used at higher voltages
Wait for the duet 3 6XD, allowing external drivers to be used at higher voltages
Use a supported STM32 board to run external drivers to be used at higher voltages
Use an Octopus Pro or Super8 v1.1 to run 5160HV stepsticks at voltages up to 60v

rexx

@deckingman thank you for your reply i am comfortable with set up of the duet 2 and ideally would be great if it could i may just giver her and try again thanks for your guidance here

Cheers

rexx

@jay_s_uk great view on the 48volt side thank you,
the stock stratasys i have was 36-48vdc hybird steppers i had planned on your #6 super fly 8 with (x3)HV5160 mellow board but kinnda wanted to look at keeping the printers on the same platform(duet) thus the duet line up investigation i had no idea the 6XD exsisted thanks to you again
but option 2 seems best as is does not need external drivers but maybe not so...
is the Duet 3 much diffrent then the 2 in set up ease diffrances?

xyz on the nema 23s 3 HV (would this mean i could only send 48v to the 1HCL and the duet 3 can be 24vdc still?)or up to 32vdc
ext1 ext2 nema 17 ht pancake 2 24v regular 5160 board mount

heated chamber with thermal fuse is on ssr mains power but i have like 8x 24vdc fans (11.5 watt-.48A each) 6 of wich on 100% is fine and 2-3 require PWM control +6 optical switchs one is ABL so the duet 2 meets the needs hummmm....

#2 #4 and #6 will be like sheep jumping over the fence tonight mayeb tomorrow too!

Cheers Jay

rexx

@arnold_r_clark
do you know materials with near 0 z layer adhesion loss are around blown film and injection are old and still used today for good reasons but the why nots of FDM printing limits are dropping off every day from flow rate to speeds and accelrations and HT thermos (500C)wich are not getting made in your garage for less than 50+K in machinery and tooling plus the three phaze power transformer power it draws and so on , but FDM will be 95% of your product agreed but the parts gets in where it fits in,
have a look at PEEK PEK PEI PPSU PESU materials and data sheets do you mould any of thease? note the temprature resistance and ASTM Tests injecton small parts in ht materials ok but to make large parts in thease HT tempratures are simply not practical the tooling alone is not fair for less than 100 pcs runs or even 10000 pcs

jay_s_uk

@rexx The super8 1.1 allows you to run 3 drivers at 48v, 5 at 24v or 5 at 48v and 3 at 24v or all 8 at 24v or 48v. The octopus pro allows you to pick and choose which driver runs at 48v. Mellow have just released an external 5160 driver that allows you to use any stepstick type board with 48v. These 2 boards essentially run the same firmware as on the duet boards but don't have the expansion capabilities provided by CAN-FD https://www.aliexpress.com/item/1005004229433552.html

xyz on the nema 23s 3 HV (would this mean i could only send 48v to the 1HCL and the duet 3 can be 24vdc still?)or up to 32vdc

Yes, you could just operate the 1HCL's at 48v and the duet 3 at up to 32v.

is the Duet 3 much diffrent then the 2 in set up ease diffrances?

I would definitely go duet 3 over duet 2 as the duet 2 is almost (but not quite) at its flash limit so it won't be seeing certain new features going forwards (such as concurrent gcode streams). Setup is just the same between them.

rexx

@jay_s_uk

Jay you have been a great help again cheers and thank you

rexx

@jay_s_uk

Good Day!

so i went with the 6HC yes.... feel good about it sofar but this swap is for a heated chamber BL touch is not gonna happen and i want to use a optical 4 wire end stop (OPB- 880T51) and would like to use this for ABL do you know how i would set it up on the 6HC if i can? there are side stops that will deply and retract the interaction with the optical switch from in use to not.

red,blk,grn,white
rd,bk,gn,we

2 anode and two cathode

it is the stock switch for the z foam in a stratasys 768

i will just have to insert the G code for where to travel to the bumps to deploy and retract when done! (one on each side at the rear out side the bed as travel permits)

any thoughts are much appreciated
cheers

dc42

@rexx thanks for choosing the Duet 6HC.

That opto switch you linked to is obsolete, but is similar to many modern slotted opto switches. What you need to do is:

Connect the IR LED side (pins 1 and 2 according to the datasheet I found at https://datasheetz.com/data/Sensors, Transducers/Optical - Photointerrupters - Slot Type - Transistor Output/OPB880T51Z-datasheetz.html) with a series resistor) across either +5V or +3.3V and ground. Choose the value of the series resistor to pass about 10mA through the LED. That means about 180 ohms if you are using 3.3V or about 360 ohms of using 5V. The exact value is unlikely to be critical. The datasheet indicates that pin 2 is the ground side.
Connect the emitter of the output (pin 4) to ground, and the collector (pin 3) to one of the IOx_IN pins.

rexx

@dc42

so resistor from pos+3.3 or 5v to Ground?(have to double check this one)
if i use 3.3v could you guide me to a resistor i could use for refrence? and would this 180 OHMS be in the circuit or just the resistor alone?
wired series resistor is not directional are they?(does not matter which direction)?
maybe a 2 wire replacement would be simpler and faster for me to get and fit but maybe i am over complicating it (sensorless homing.....)

my oem x and y are two wire opto but diffrent in size and dont fit for the z Probes switch but would guess they would goto an IO with GND and io#in? they are Normally Closed

dc42

@rexx you need a resistor from the IR LED anode to +3.3V or +5V, and connect the IR LED cathode to ground.