Abstract: A meter stack wherein each single phase meter base in the meter stack can be selectively connected in the field to any one of the A-B, A-C or B-C phase combinations of the vertical three phase bus bars in the meter stack by moving only the meter base line connectors. The vertical bus bars of the meter stack lie in a common plane and are equally spaced apart from one another. The vertical center line of each meter base in the meter stack coincides with the center line of the center vertical bus bar of the meter stack. Each of the two line side terminals of each meter base is associated with one of the outside vertical bus bars, and is located approximately half way between it's associated outside vertical bus bar and the center bus bar. A generally "Z" shaped line connector attached to each of the line terminals can be easily rotated between its associated outside bus bar and the center bus bar, thus easily allowing a change in the A-B, A-C or B-C phase combinations of each meter base.

Abstract: An optical switch operating mechanism including a housing cooperatively preventing dust and light from easily reaching an optical switch supported within the housing. The housing includes integrally formed spaced apart slots for receiving the optical switch and an associated integrally formed tubular shaft for slidably receiving a switch operator, a portion of which extends outside the housing. The tubular shaft is positioned between the spaced apart slots such that the longitudinal axes of the shaft and it's associated pair of slots and are perpendicular to one another. A light passage, also integrally formed with the pair of slots and associated shaft, passes through the shaft connecting the associated pair of slots such that light from the optical switch emitter can be received by the optical switch receiver when a window in the switch operator is aligned with the light passage.