I have 47A 12V server power supply for my 3D printer project. The idea is to add a relay before printer hardware (RAMPS, Arduino Mega clone, steppers, bed heater etc). The normally open relay is then controlled by a separate Arduino Uno which monitors temperature sensors inside printer enclosure and sends constant signal if everything is ok.
For an automotive relay I would need to use an opto isolator to control a 12V line as Arduino Uno signal won't be enough to energize the relay. With SSR I guess could avoid that but is there any other benefit of using SSR instead of automotive relay.