The article discusses a hammer operation technique, the drive of which is a linear electrodynamic motor. The relationship between the current pulse in the rotor field winding with impact energy is studied. In static mode of the electrodynamic hammer the currents are fed to coil winding and the rotor field winding, the current magnitude is sufficient to draw the rotor into the stator and keeping it in the upper position. Then current pulse is fed to the rotor field winding to provide the rotor stroke. The direction of the current pulse is the opposite to the current direction in the static mode. Current pulse duration is shorter than it takes to reverse magnetization of the stator magnetic core, but it exceeds the duration of the rotor stroke. The results of tests of electrodynamic hammers are presented. Keywords: electrodynamic hammer, current pulse, time of magnetization reversal, magnetic core, rotor.