Testing system for petroleum wells having a fluidic system including a gas leg, a liquid leg, and bypass conduits in communication with multiple multiphase flow metering systems with valves to control fluid dlow through the fluidic system

A well test system for testing fluids produced from one or more petroleum wells has a separator and a plurality of multiphase flow metering systems, each of which has the capability, over at least a portion of its operating envelope, of separately measuring flow rates of oil, water, and gas. The well test system has a fluidic system, including gas leg conduits coupling the separator to the multiphase flow metering systems, liquid leg conduits coupling separator to the multiphase flow metering systems, and bypass conduits for directing multiphase fluid to the multiphase flow metering systems while bypassing the separator. Valves are configured to selectively route fluid flow though the fluidic system to selectively bypass the separator when the multiphase flow metering systems can be used to provide separate flow rates of oil, water, and gas in the unseparated multiphase fluids from the well