Abstract: A drive unit for use with a vibration welder having first and second electromagnets, each having first and second terminals, and being operable to reciprocate a vibration platen, includes phase U, V, and W drive circuitry and control circuitry. The phase U drive circuitry is coupled to the first terminal of the first electromagnet. The phase V drive circuitry is coupled to the first terminal of the second electromagnet. The phase W drive circuitry is coupled to the second terminals of the first and second electromagnets. The control circuitry is operable to control the phase U, V, and W drive circuitry to generate a first drive signal for energizing the first electromagnet and a second drive signal for energizing the second electromagnet.

Abstract: A method for diagnosing the linkages of an inverter including a controller connected to switching devices that are between a DC input and a multi-phase output. The inverter can be diagnosed to determine whether the control signals provided to the switching devices are being properly provided to the inverter and whether the inverter is operating properly. Diagnosis of the inverter is advisable upon commissioning or after completion of a repair. The controller can provide at least one signal to the switching devices and the signal can be monitored adjacent to the switching devices to ensure that the switching devices are receiving the correct signals from the controller. The controller can provide at least one signal to the switching devices and the output of the inverter can be monitored to determine whether the inverter operates in accordance with the provided signal.