Abstract: Methods and systems for smart transfer switch circuits and operation, and for operation of transfer and/or cutoff switches in combination with a power-packet-switching-architecture (PPSA) power converter. The transistors of the transfer and cutoff switches, and the transistors of the phase legs of the PPSA power converter if present, preferably all use double-base bipolar transistors which have low on-state series resistance as the switching elements.

Abstract: Methods and systems for smart transfer switch circuits and operation, and for operation of transfer and/or cutoff switches in combination with a power-packet-switching-architecture (PPSA) power converter. The transistors of the transfer and cutoff switches, and the transistors of the phase legs of the PPSA power converter if present, preferably all use double-base bipolar transistors which have low on-state series resistance as the switching elements.

Abstract: Automatically determining issues associated with a photovoltaic (PV) system. Information regarding the PV system may be stored. The information may include logical information regarding a logical configuration of the PV system and physical information regarding a physical layout of the PV system. Measurement data regarding the PV system may be received. The measurement data regarding the PV system may be automatically analyzed using the logical information and the physical information. An indication of any issues determined by said analyzing may be automatically provided.

Abstract: A multiplexed data communications modem providing high speed data communication via a single twisted pair of conductors having a distance up to two kilometers between a plurality of data terminals and remote communications equipment is provided. A burst mode ping-pong transmission scheme is utilized. A control portion selectively multiplexes data from each data terminal, and the variation of actual data rate of each data terminal has no effect on channel capacity of the other multiplexed data channels. A plurality of data interface circuits provides an asynchronous/synchronous interface between the multiplexed data terminals and a synchronous transceiver.

Abstract: A torque limiting clutch having a torque limit which is easily calibrated and relatively constant throughout the service life of the clutch. The clutch includes a pair of rotatable members which are rotatably coupled by resilient friction members yieldably engaging one of the pair of members and securing to the other of the pair of members. The friction elements are configured to achieve substantially uniform friction force and wear along their friction surfaces. According to one embodiment of the invention standard commercial snap rings may be employed as the friction elements.