So tonight moved machine manually and i think the steppers backfed and blew the fuse for the low volt side. I was able to power it by usb to use it, but i think it needed more as it paused alot while working.
The stepper side still seemed to work ok.
Shooukd i a) replace fuse b) use with a power cord to the arduino or replace the ramps board?
A Ramps board by itself costs only $9 from Amazon and you can get it for less than half that price on Aliexpress. At that price point, I personally would be tempted to just replace the board rather than messing around with fixes or workarounds. If you don’t already have them, the fuses will likely run you a significant portion of $9.
Yea like said just fast enough evidentally. I have them connected in series so that probably does not help. It has always lit the lcd if off. I just need to decide what to do.
There’s also the solder blob bypass trick… most USB ports already have OC protection built in anyways.
I wouldn’t use the 'duino LDO. Those are only good for small fries, and a cnc RAMPs may need more 5V for stuff like relays, TFT’s, etc. I’d bypass the fuse or replace the ramps… or better yet if you can, take a fuse from an old device and slap it on top of the blown one.
I got a chuckle reading your comment about the LCD lighting up. I used to use that as my ‘manual move speedometer’. “We’re just looking for a low glow here, if you start seeing characters you’re pushing it too fast.”
It’s also possible you blew a voltage regulator rather than a fuse. I’ve replaced them (unsoldered/resoldered) in the past, but at this point the part ala-carte with shipping ends up being more expensive than a whole new ramps setup.
If your display only lights up when the Arduino is powered by USB, that’s a symptom that the 5v regulator got fried. I used my 3D printer powered through both USB (for logic power) and 12V power supply (for motors and heaters) for a couple of weeks with no problem while waiting for parts to come in. During this period I used Repetier Host to start jobs, I didn’t print from SD cards.