20A Power Supply is below 23.5A peak Duet 2 Wifi capacity - do we need more safety margin ?
Hi Ben and fellow enthusiasts.
My question arises after consulting the Duet Wifi 1.04 specs which indicates it could draw up to 23.5A with the installed fuses (1A for the fans, 7.5A shared for hotend heaters and stepper motors, and 15A for the heated bed). I also note the hardware is designed to be capable of drawing even more current (2.8A per stepper and 18A bed). Summing up the components of the BLV Cube build, I get to roughly 20.41A peak current demand (Hot end cartridge 30W/24V = 1.25A, CR-10 Heated bed 220W/24V = 9.16A, 5 x Stepper Motors 2A = =10A, fans negligible).
Forgive my naivety, but when I choose a PSU for my PC, I always buy more watts than my expected peak demand. I don't understand these things in depth, but I'm worried the suggested PSUs for the BLV cube don't offer enough "safety" margin, especially when using unbranded PSUs which may lack quality control or safety shut off features.
I feel that peak current situations could occur during pre-heat and at the same time if there was a bed/head movement binding issue that would cause the steppers to be sent loads of current. I know that's worst case scenario, but...
What do you reckon guys and girls ? I would welcome your words of wisdom.