Pump Control of a misting system is not mandatory. You can plug it and turn it on, but you almost guaranteed to run into some sort of trouble. Yes, pump trouble. Without some safety's you pump will eventually die, probably as sudden death. Death typically from lack of water supply.
Misting pumps need a little bit of control to have some sort of reasonable life expectancy. Determining which safeties are more important that others can be difficult. Much of it depends on the size of the system, cost of the systems and it applications.
Water Input Pressure Safety Switch is first on the list.
Water In Pressure Switch
Probably the most important. Running a pump without water is certain failure. A typical hihg pressure pump needs water or it will die. Pressure switches shut down the pump when the water supply get cut off. Human error or filter clog are the two main causes.
Water Out Pressure Regulator
Pressure regulator are generally included with the pump. Sets you output pressure. The pressure applied to your misting nozzles.
Water In/Out Pressure Gauges
You need to know your pressures. Both In and Out are important. Two on the input is nice. One before the filter and one after. The one after the filter is the important one. Tells you if your filter is clogged.
Water Out Temperature Relief
Quality pressure pump assemblies will monitor water out temperature. Water recirculates through the regulator. To much recirculation increases water temperature. At 140 deg. F it will relief itself, discharge itself to get cooler water in the pump.
Water out must be at least 20 percent of pump capacity. Don't oversize your pump.
Water Out Pressure Relief
Quality pressure pump assemblies also have pressure reliefs. To high a pressure can damage the pump, pump motor, and other assemblies that are not rated for high pressures. They are set by the factory for the assembly purchased.
Water Out Pressure Switch
Water out pressure switches start to fall into more advanced pump control. They shutdown the pump if there is a leak on the output high pressure side. A nice feature. Keep the floods a bay, eliminates them.