I'm assembling a complete electrical system for a pickup. I'm going to be using Bussmann 15404 fuse/relay boxes. They use Micro-280 relays.
I see some of these Micro-280 relays have a flyback diode built in, and others substitute a resistor for the same purpose. Something I read, indicated to use a diode for motor loads, and to use a resistor for resistive loads. This makes no sense. It's the switching circuits upstream that are at stake; not the switched load.
Can someone explain why I should use one or the other?