An assembly arranged in a well bore and run in conjunction with a perforated or a non perforated liner has an inflatable packer section prepared for being expanded by fluid and a valve device for opening and closing of fluid communication into the inflatable packer section. The assembly also has a fluid section connected to the inflatable packer section. The fluid section holds a fluid that is delivered into and used to inflate the inflatable packer section. An energy section in the assembly contains an energy source for delivering the fluid from the fluid section into the inflatable packer section. A triggering section includes a control for the energy source and/or the valve device. The triggering section can control the delivery of the fluid into the inflatable packer section. The triggering section also includes a communicator that signals a triggering device for initiating the expanding of the inflatable packer section.