Loop L_uni: the temporal variation in energy (magnetic, internal and kinetic), heating (Ohmic and viscous) and maximum current for ideal MHD (top row), for resistive MHD with η_b = 0 (middle row), and for η_b = 10^-4 (bottom row). The initial magnetic energy has been subtracted from the magnetic energy plots (solid lines, left column). The critical current (J_crit = 15) is indicated by the grey dashed horizontal lines (right column). For the η_b = 0 case, the maximum current plots are from the high (black) and low (grey) resolution simulations.