Abstract: An assembly for transient and continuous testing of an open portion of a well bore arranged in a lower part of a drill string includes at least two packers fixed outside of the drill string, which are expandable for isolating a reservoir interval. The assembly includes a down-hole pump, sample chamber, sensors, closing valve, sensors and telemetry for measuring and realtime transmission of flow rate, pressure and temperature of fluid flow from the reservoir interval, from the down-hole pump, in the drill string and in an annulus above the packers, a mud driven turbine or electric cable, and a circulation unit. The circulation unit, independent of the circulation rate for mud to the annulus, can feed formation fluid from the reservoir interval into the annulus, so that at any time a well can be kept in over balance and the mud can solve the formation fluid from the reservoir interval.

Abstract: An assembly for transient and continuous testing of an open portion of a well bore arranged in a lower part of a drill string includes at least two packers fixed outside of the drill string, which are expandable for isolating a reservoir interval. The assembly includes a down-hole pump, sample chamber, sensors, closing valve, sensors and telemetry for measuring and realtime transmission of flow rate, pressure and temperature of fluid flow from the reservoir interval, from the down-hole pump, in the drill string and in an annulus above the packers, a mud driven turbine or electric cable, and a circulation unit. The circulation unit, independent of the circulation rate for mud to the annulus, can feed formation fluid from the reservoir interval into the annulus, so that at any time a well can be kept in over balance and the mud can solve the formation fluid from the reservoir interval.