Abstract: An electric control system with mechanical interlock characterized by means for switching between one or another supply line extending to a load which comprises two parallel paths extending to the load which path includes spaced controlled devices, and rotary mechanical interlock timing means between the several control devices for sequentially preventing closing of two or more control devices at the same time.

Abstract: A compressed-gas insulated circuit breaker including two spaced apart electrical conductors within a sealed housing, a stationary contact electrically connected to one of the conductors, and a movable contact connected to the other conductor. The movable contact is coupled to a drive mechanism comprising a contact rod secured to the movable contact at one end, and pivotally coupled to a connecting rod at its other end. The connecting rod is pivotally coupled to one of a pair of arms fixedly secured to a rotatable positioning shaft. The other arm is pivotally coupled to a drive rod, and the drive rod is pivotally coupled to a centrally rotatable drive latch. The drive latch is secured to a rotation means, and upon rotation of the drive latch, the drive rod is moved, causing a rotation of the positioning shaft. Upon rotation of the positioning shaft, the connecting rod is moved, causing a longitudinal movement of the contact rod and the movable contact.

Abstract: An improved multiphase compressed-gas circuit-interrupter installation is provided having compact, serviceable and inexpensive operating arrangements with an improved gas-leakage detection arrangement and system for detecting a loss of high-pressure gas in each of the multiphase circuit-breaker modules to the exclusion of the other adjacent circuit-breaker phase modules.An improved operating-linkage rod-assembly is provided extending across the front of the circuit-breaker installation, and readily available for easy servicing and adjustment, so that synchronism of the control valves in the several phase-units, or pole-units may be achieved.

Abstract: An improved multi-phase compressed-gas circuit-breaker installation is provided having the three or more circuit-breaker assemblies mounted upon a horizontally-extending rigid frame structure, with the high-pressure and low-pressure gas-reservoir tanks disposed close to the ground, and having the circuit-breaker assemblies extending upwardly in spaced lateral horizontal relationship. Pressurized pipes, or conduits connect to the circuit-breaker assemblies, the pressurized pipes containing, of course, the internal high-voltage power-conductors at the centers of the pressurized pipes, as well known by those skilled in the high-voltage power-transmission art of the pressurized gas-insulated type.

Abstract: An improved gas-heating means is provided for a multi-phase gas-type circuit-interrupter, all phases being supplied with high-pressure gas from a single high-pressure reservoir tank by suitable baffling means spaced longitudinally along the high-pressure reservoir tank, together with hot and cold inlet and outlet pipes leading into the separate upstanding circuit-breaker columns, or modules, controlling the individual phases, with the cold outlet pipe, preferably, extending downwardly toward the lower end of the high-pressure reservoir tank, and the hot inlet pipe located, preferably, at a higher elevational level than the cold outlet pipe, for thereby promoting proper heated gas circulation into the upstanding circuit-breaker modules.