what is the amperige of flsun 300 x 300 heatedbed?

electronics flsun FLsun_2017 FLSUN_Cube flsun_i3 Heated_Bed kitchen math

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I wonder if anyone have meassured ampperidge or wattage of 300 x 300 mm heatedbed
I'm trying to calculate wire thicknes for bed it is 4 mm2 from factory. it feels little thick I think.
thank you for thinkering this with me.

Thank you all! so all power goes to bed power supply is 30 amp.
Offcourse it divides as hotend kicking in and steppers are working.
I do not want to start printting by burning my house down.
thank you for answers again!!
good spring to you

At 30 amps, they’re actually a little on the thin side.

I agree. I would argue my connections were very tight and secure, but this image shows otherwise. My power supply connection melted some months ago so I moved to a Dell Server Power Supply that's supposedly capable of delivering 60amps.
I've had no other issues. The FL Sun was working for at least 6 months before the burnt connection.
After that, I just soldered all my connections to the PCB bypassing the screws and those thin PCB mount points.
The 30 Amp power supply has been in storage and from the looks of these numbers, that was a good choice. 30Amps seems like a great power supply for a smaller 200x200ish bed and printer. I'll eventually use it in another printer or project.

I measured the DC side (not the AC side) plugged into 120V (US)
27Amps for the Bed only (actively heating) 322Watts (At 12V)
29.9 Amps for the Bed and Extruder (actively heating) but no motors active (was only heating, not printing)

If you measure the resistance and know the voltage you can plug it into an ohm's law calculator like here:
Then there are charts on the internet for determining wire gauge based on wire length and amperage and voltage like here:
Note that a 24v system requires much smaller wires than a 12v system.

Actually measuring the current is more accurate because when the bed heats up the resistance changes.

Using a wire gauge table is always a good idea. The trouble with the cables supplied in the Flsun kits is that it is of low quality and not suited for the many times it will be flexed/bent over a period of time. Then there is the poor plug connectors that will come loose and/or melt. Solder the cables directly to the bed and use good crimped connectors on the other end.

I used the method I describe when upgrading to a 24v silicone heater to pick my wire size and my wires don't even feel warm.
Two minutes to 110 degrees is very nice :)