SDean wrote:A quick rule of thumb to use with devices like fans is that if they have a steady state draw of xA, then the startup draw will be 4xA, thus a device that runs a steady state draw of 5A needs 20A on startup. The radiator fan in my car draws ~6A running, with a 25A draw on startup through the PDM.
But just for clarification, the PDMs all ignore extraordinary inrush current provided it is of sufficient short duration, no? So for example, my radiator fan draws 20+ amps when running, and I drive it with two 20-amp PDM outputs without issue. Theoretically, inrush current could be 80+ amps, but so long as it doesn't last for more than a second or two, the PDM tolerates it.
--Peter