Is this re-Arm controller actually 24 V capable?

1

I would like to make a 24 V (3D printer board and shield) setup, as opposed to the usual 12 V, and to do so I had been considering using the Taurino Power board, or the clone Eruduino. However, I just found this board:

Re-ARM microcontroller, with SD card slot

The specifications state a DC input of up to 36 V:

Specifications

Does anyone know whether that really means it can handle 24 V in the same manner as the Taurino/Eruduino? If so, then that looks like a double win: not only 24 V support, but also a faster processor. Anyone have experience with this board?

I was thinking of using with a RAMPS1.6 Plus (maybe), or just a regular RAMPS 1.4 (hacked to support 24 V). I'm just shopping about, and I thought that if I was going to spend £14 on an Eruduino, then I just as well spend that money on something better.

It does work with Marlin apparently, as some of the customer reviews would suggest, but none of the reviews that I could find referred to a 24 V setup (heated bed etc.), hence my question.

Greenonline

Posted 2019-07-15T09:06:13.603

Reputation: 5 004

Answers

4

Given that the capacitor near the input is quite clearly marked 35 V, a 36 V rating seems questionable.

The (buck) regulator used on the (genuine version of the) board is the AOZ1282CI which supports up to 36 V input. This is probably where they got the 36 V rating from, but obviously the 35 V-rated capacitors drop the input voltage down below this.

Schematics for the board are available on the RepRap wiki and show that the input voltage only feeds into the regulator. I see no reason why this board couldn't handle 24 V input, as this is well within the rating of both the regulator and the capacitors.

Tom van der Zanden

Posted 2019-07-15T09:06:13.603

Reputation: 14 003

Ah, well spotted! – Greenonline – 2019-07-15T09:29:38.680

2

For completion, I've just seen this, Can a ramps 1.6 support 24v? (which basically confirms the 24 V support of the Re-ARM board) although it isn't particularly useful w.r.t. the RAMPS 1.6 side of things, although I would imagine the the 24 V RAMPS hack would still apply.

In addition, Alex Kenis does a great review, and he has successfully tried it with 24 V, watch 32-bit series part 4: Re-ARM board "review?". Whilst the RE-ARm offers a lot of advantages, some of the main down points to be aware of are:

  • No 5 V analogue inputs, they are 3.3 V, so the endstops use 3V3 logic (not a problem from mechanical switches, but 5 V optical endstops will have a problem
  • Some of the pins of the Mega are missing from the Re-ARM.

Greenonline

Posted 2019-07-15T09:06:13.603

Reputation: 5 004