The possibility of the magnetically self-insulation regime at pulse duration of 3–4 µsec has been shown. Information on characteristics, dynamic of electron flow and cathode plasma in the line has been obtained. It has been found that unlike hydrodynamic model the electron flow in the line has no clear-cut external boundary but entirely fills the inter-electrode gap. In the vicinity of the external electrode the current density increases in the direction to the line axis. The operation of the line with misaligned electrodes have been investigated.