This is my latest attempt to try building a ups ish system for my 3D printer the printer is custom-designed with 5 meters (no, it's not a typo) on each axis.
we use MKS Gen v1.1 with custom marlin core.
this board can handle 12-24v.
with our calculation, our current draw is 20 to 60 amps when bed and nozzle are heating up.
so a commercial UPS is not affordable.
I came up with the following circuit as our power source.
I could use some tips to optimize it.
I know it's not pretty
My charge controller is Arduino Mega with the following algorithm:
if the battery voltage drops below 11.5 the relay is connected to charge the battery up to 13 volts then the relay is disconnected.
V1 is a power source with 80 amps capacity.
V2 is 3 car batteries connected in parallel. (to handle the sudden current shock)
There is a backup generator behind V1 which starts if V2 drops below 11.2.
There are other loads on the printer side that are mission-critical and can not be turned off even for 1 second.
P.S: I was thinking about adding a capacitor to smooth out the voltage but I could use a bit of help to calculate its capacity.
P.S2: we are planning to add solar panel as V3 later this year...
P.S3: I know, I know its idiotic, but we are tight on budget and cannot afford a big UPS we are pretty much out of money and this printer is our income source ...
( it took me around 35 days to build this printer, speed is 3mm/min, it's huge )