Abstract: Plug-on enclosed fusible switches, enclosed lug devices and non-enclosed molded case circuit breakers are attached to a panelboard in a single or side-by-side double row. Spring biased latches retain the devices to the panelboard. Locating notches on the panelboard locate the devices at incremental spacing to provide a variable, compact arrangement for the devices. Filler plates and end structures on the devices cooperate with a cover for the panelboard to provide an integral dead front. The panelboard is particularly adapted for field assembly, including attachment of a main feed device which effects a plug-on feed in either a single or electrically parallel double panel arrangement.

Abstract: Plug-on enclosed fusible switches, enclosed lug devices and non-enclosed molded case circuit breakers are attached to a panelboard in a single or side-by-side double row. Spring biased latches retain the devices to the panelboard. Locating notches on the panelboard locate the devices at incremental spacing to provide a variable, compact arrangement for the devices. Filler plates and end structures on the devices cooperate with a cover for the panelboard to provide an integral dead front. The panelboard is particularly adapted for field assmebly, including attachment of a main feed device which effects a plug-on feed in either a single or electrically parallel double panel arrangement.

Abstract: A heat exchanger preferably of the type for heating water from hot gases or steam comprises first and second tubes arranged concentrically so as to define a channel inside the first tube, an annular channel between the tubes and a further channel outside the outer tube. The hot gases are arranged to pass inside the inner tube and outside the outer tubes so that water passing through the annular channel is heated from both the inner and outer surfaces. Such an arrangement can be built up into a total heat exchanger by an array of such co-axial tubes arranged side by side or by an array of such co-axial tubes arranged co-axially, that is with further tubes outside the outer tube. Baffles in the form of radial fins cause the fluid to move along an underside of the baffle toward a closed end and then to turn at the closed end back along an upper side of the baffles toward the outlet.

Abstract: Stationary contacts (12) of a multi-pole disconnect or safety switch are arranged to be engaged by one of a rotatably movable bridging contact (2) before engagement of the other end thereof with a second set of stationary contacts (10). Stationary contacts (12) of adjacent switch poles are positioned on alternate ends for increasing the phase-to-phase failure distance, and one stationary contact (10a) may be arranged to close one or two milliseconds late to produce single phasing for a short time under fault current conditions during which time current limiting fuses (14) begin to open the circuit.