# Auto squaring and current limit with RAMPS

The max current from input to steppers on RAMPS is capped to 5A . With 5 steppers @ 1.35 A (90% of 1.5A), the max possible current is 6.75A. This worries me that the fuse might blow up when cutting a circle or something that engages all the axes at the same time. I am using steppers that are spec’d for 2A but I can adjust it to run at lower current but the 5A cap worries me. Has anyone been running ramps in duel endstop config long enough to be confident that it will work? Thanks!

You need to try all that again but work in Watts, Amps is only half the info.

12V 3A=36W

2V 3A = 6W

But fuses work with respect to amp. So the example you showed will blow up a fuse that is rated @ 3A.

Absolutely.

The fuse is determining the capacity of the lines based on the input, in watts with respect to the input voltage. Do your calcs in watts and don’t pay attention to the fuse for now I think you will understand it is not even remotely close to something you need to worry about. I have it written here what the amp draw is but it would be best if you check it yourself. Then you can double check it with a mulitmeter.

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Thanks Ryan. I will give it a go and see how things turn out. Have already cooked a ramps board because I am stupid and plugged it to 24VDC (I was previously running my mks board at 24VDC) since the spec saied 12-36VDC which is not possible out of the box (learnt it the hard way).