The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 26, 1992
Filed:
Mar. 14, 1991
Roger R Roth, Minnetonka, MN (US);
Honeywell Inc., Minneapolis, MN (US);
Abstract
An electric power consuming system such as the lighting in a building has local control units for adjusting the power consumed by a preselected load or loads associated with each local control unit. The control units generate a selectable control voltage which has a first range specifying to the loads that no power should be consumed by the loads with voltage outside the first range specifying by its level the amount of power which the loads should draw. The system also includes energy management apparatus whose output is connected across the output of the control units and which can limit the power individual control units can specify to their loads. The invention comprises an interface circuit which connects the energy management apparatus to the control units and translates control voltages from the energy management apparatus falling within a second voltage range within the first range of the selectable control voltage, to a voltage falling outside the first voltage range. The energy management apparatus is of the type which during common failure modes, provides a control voltage within the second range. In this way, safety is not compromised by reason of malfunctioning energy management apparatus turning off lights in occupied areas.