I am making a PCB for which I need advice on widths of power traces. I am powering a 3A pump and a 1A solenoid valve through this PCB. I am drawing widths based on the table below.
3A + 1A = 4A. So should I draw the power traces basis 4A or should I keep a margin for surge current drawn during starting? This machine starts and stops pumps and motors every 7-8 seconds and does this for almost a thousand times a day. My problem is that if I draw for 10A then trace width of 300mils is too big to fit easily on the PCB. If according to theory surge happens only momentarily upon starting, shouldn’t 150mils be enough?