The drawing provided here is an example of a full-bridge (H-bridge) inverter. This is a typical single-phase inverter made up of a DC source, switches (most commonly IGBTs) to route the drive current, freewheeling diodes to dissipate inductive currents and complex control devices (not shown) to manage the switching timing. By turning different combinations of switches on and off, the load will see an alternating current. With T1 and T4 on (T2 and T3 off) the load will see +Vs. With T2 and T3 on (T1 and T4 off) the load will see –Vs. With T1 and T3 on (T2 and T4 off) and T2 and T4 on (T1 and T3 off) the load will see 0V. The diodes allow both the negative and positive currents to return to the source during the “dead-time” transitions between the switching states. T1 and T2 (also T3 and T4) can never be on at the same time as this will cause a direct short across the link. Therefore a timing period is needed where both switches are off before a transition can take place. This is called dead-time and it is in these time periods that the free-wheeling diodes conduct.