A power supply supplying electric power through parallel operation of power supply units is disclosed. Each of the power supply units includes a transformer; a stopped state latch part configured to latch a control signal for controlling outputting of the power supply unit in a predetermined stopped state to stop the outputting, after passage of a first time in response to detection of an overcurrent on a primary side of the transformer; and an outputting restriction part configured to set the control signal in a predetermined restricted state to restrict the outputting of the power supply unit without stopping the outputting, after passage of a second time in response to detection of an overcurrent on a secondary side of the transformer. The second time is shorter than the first time.