Dual control device limit on appliances das electrical measurements

摘要

Control device dual limit on electric measuring, characterized in that it comprises the scale plate two manually mounted rotatable external controls jointly with each of the axes on which are arranged respective drive elements through which revolve respective concentric rings, one of which, the larger diameter, is rotatably mounted on the contour of an opening in the plate of the scale, while the other is carried by the first; finding mounted jointly limit the pointers in each of the rings; and because when the two needles are positioned on the scale, and the pointer of the apparatus is in the field limited between them as any coincidence in position of the pointer with the needles limit is detected by an optical device that sends signal, to an electrical circuit that will trigger a relay whose contacts maneuvering an external alarm.