Doesnt seem to matter, bosch rotary or p7100 low pressure will kill either fuel injection pump. Low pressure will also take away fuel and that means less power. I will have both, low pressure warning light and gage. the gage will be off to the side, the light right out front. I also will have a pressure switch on the engine cooling system... if the cooling system pressure light comes on, then check for leaks and watch temperature gage. Exhaust gas temperature gage, exhaust manifold pressure, intake manifold pressure. There will be two oil pressure warning lights, one that is a low pressure- idle oil pressure, and one for higher speed, 1200 rpm and up higher pressure. oil temperature gage too.
From reading about the 12 valve cummins, you have a problem with less than 15 psi - this is the pressure of the fuel as it is fed to the main injection pump. Pump damage may occur from low pressures. It is reported that power will drop with pressure at this level. Many report that at idle 20 to 25 psi and at 2500 to 3000 look for 30 to 35 for most power.
I hope this is of service to you.