Abstract: In an automatic transfer power supply with relay protection, multiple electric power sources may be selectively coupled with a switched-mode power supply circuit using multiple corresponding sets of relays. The switched-mode power supply circuit may include one or more switches that operate under the control of a switch controller element to implement the functionality of the switched-mode power supply. To protect the relays during source transfer, a source transfer controller may signal the switch controller element to halt current flow through the switched-mode power supply circuit, and then signal the relays to change state while the current flow is halted, thereby protecting the relays during source transfer. Sparking may be reduced in relays that physically move metal armatures to make and break electrical connections, prolonging relay life and/or reducing relay failures and improving power supply availability.

Abstract: A solid-state automatic transfer switch includes a primary rectifier circuit and a secondary rectifier circuit, wherein at least one of the rectifier circuits includes one or more controllable semi-conductor switches. The primary rectifier circuit is electrically coupled to a primary input and an output of the solid-state automatic transfer switch. Also, the secondary rectifier circuit is electrically coupled to a secondary input of the solid-state automatic transfer switch and the output. A controller controls a control state of the controllable semi-conductor switches to allow or prevent electrical power from flowing through the primary or secondary rectifier circuits, thus selectively controlling whether power is fed from the primary input or the secondary input of the solid-state automatic transfer switch to the output of the solid-state automatic transfer switch.

Abstract: Systems, devices, and related methods for automated testing of an automatic transfer switch. A device for testing an automatic transfer switch includes a primary power supply input, a controlled primary power output, a primary power source selection assembly, an output electrical power monitor unit, and a control input. The power source selection assembly is controllable to enable selective communication of electrical power received via the primary power supply input to the controlled primary power output. The output electrical power monitor unit is configured to monitor electrical power supplied to a connected load via the automatic transfer switch. The control input is operatively coupled with the primary power source selection assembly and the output electrical power monitor unit to enable control of the operation of the primary power source selection assembly via an external controller and to transfer output from the output electrical power monitor unit to the external controller.

Abstract: Techniques are described for providing an automatic transfer switch (ATS), such as in a data center, to determine whether the power system coupled to a first power input on the ATS is the same power system or a different power system that is coupled to a second power input on the ATS. The ATS determines and compares the electrical characteristics (e.g., voltage, current harmonics, etc.) to determine if there is a difference between the determined characteristics. If the electrical characteristics are substantially similar, then a single power system is coupled to both power inputs on the ATS. But if the electrical characteristics are significantly different (e.g., the difference in the electrical characteristics is above a threshold), the power system coupled to one power input on the ATS is different from the power system coupled to the other power input on the ATS.