The pumps run continuously, and if used with a deadhead regulator they will heat up significantly, which can shorten the life span of the pump . Most manufacturers want a return style regulator to be used, so the fuel flowing through the fuel pump can cool the pump.
I used a Fuelabs two speed pump with a bypass regulator, and mounted a small switch that triggers the higher pump speed when the secondaries open. The pump is designed to run cool and continuously at the low speed and flow a much higher volume at the higher speed. It is a 45psi pump.