Abstract:
A communication system between a plurality of electrical loads and at least one electrical measurement device is configured with a plurality of wires grouped in pairs. Each pair of wires is uniquely color coded to facilitate installation of each electrical load.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of the Invention  
         [0002]     The invention relates generally to electrical metering, and more specifically to an electrical system ergonomically configured to facilitate installation of and provide reliable reading of electrical parameters of a plurality of loads.  
         [0003]     2. Description of the Related Art  
         [0004]     Currently, various electrical meters are used for high accuracy measurement over a wide frequency bandwidth. Additionally, having a plurality of power consuming loads often requires precise measurements associated with each of these loads. For example, it may be desirable to measure voltage, current, watts, vars, frequency, power, watt-hours, var/hours, demand, harmonics, etc., for each load.  
         [0005]     Accordingly, in the conventional art, installation of a system including at least one power meter and multiple loads is typically realized by wiring and connecting each of these loads to the power meter. However, quite often, leads, wires or cables extending between the power meter and multiple loads are tangled or twisted. To discern which pair of wires belongs to the same load is a daunting task even for a seasoned professional. As a result, it is not uncommon to connect voltage and current wires belonging to different loads to the same single terminal pair. In this case, the any reading associated with a load is skewed and the information thus received can lead to serious problems.  
         [0006]     Because these electrical meters are often installed in critical applications, shutting a system down to correct for wiring mistakes is often impossible. As a result, the meter ends up reading incorrect data for an extended period of time, e.g., until an entire plant shutdown.  
         [0007]     It is, therefore, desirable to provide an installation system that clearly indicates the desired pair of wires belonging to the same load so as to avoid accidental coupling of the voltage and current wires belonging to different loads to the same terminal pair.  
       SUMMARY OF THE INVENTION  
       [0008]     It is, therefore, an object of the present invention to provide a system and method for identifying respective pairs of individual loads being metered in an electrical metering device.  
         [0009]     The above and other objectives are attained by an installation system and method in which a plurality of loads, each of which is characterized by a respective pair of uniformly colored wires, are connected to a corresponding input, which is the same color as each pair, of an electrical metering device. As a result, crossing wires from different loads while connecting these loads to an electrical measuring device is minimized. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0010]     The above and other objects, features, and advantages will become more readily apparent from the following detailed description accompanied by the following drawings, in which:  
         [0011]      FIG. 1  is block diagram illustrating an inventive installation system including a plurality of loads, each characterized by a pair of current and voltage wires, which are uniquely color coded; and  
         [0012]      FIG. 2  is a diagrammatic view illustrating one of embodiments of the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0013]     Preferred embodiments of the present invention will now be described in detail herein below with reference to the annexed drawings. In the following description, a detailed description of known functions and configurations incorporated herein has been omitted for conciseness.  
         [0014]      FIG. 1  is block diagram illustrating an inventive installation system including a plurality of loads, each characterized by a pair of current and voltage wires, which are uniquely color coded, and  FIG. 2  is a diagrammatic view illustrating one of embodiments of the invention.  
         [0015]     Referring to  FIGS. 1 and 2 , an inventive installation system  10  includes a plurality of wires pairs  50  and  50 ′,  60  and  60 ′, and  70  and  70 ′, which extending between loads  30 ,  35 , and  40  and a metering device  10 , respectively. Wires  50 ,  60 , and  70  each correspond to the voltage of their respective pairs, and wires  50 ′,  60 ′, and  70 ′ each correspond to the current of their respective pairs. Further, to avoid crossing the voltage and current wires from different loads, each wire pair  50  and  50 ′,  60  and  60 ′, and  70  and  70 ′ are uniquely color-coded. That is, for example, wires  50  and  50 ′ are red, wires  60  and  60 ′ are blue, and wires  70  and  70 ′ are yellow. As a result, regardless of the overall number of loads, the risk of crossing the voltage and current wires from different loads is substantially minimized since two wires of the same pair is identically color-coded.  
         [0016]     For example, to determine the power associated with each of the loads, it is necessary that a voltage and current of each load be measured. Accordingly, by using the colored wire pairs according to the present invention, the chances of obtaining an incorrect power reading, which is normally caused by calculating a power using, for example, wires  50  and  60 ′, are greatly reduced.  
         [0017]     Additionally, to even further minimize the risk of crossing wires, according to another preferred embodiment of the present invention, the metering device  10  is configured such that the terminals for receiving the respective wire pairs are also identified by the same colored as the corresponding wire pair.  
         [0018]     Referring to  FIG. 2 , as indicated above, such a color-coding of the terminals may be realized, for example, by having a region between the terminals of the same pair colored in red, blue, and yellow. More specifically, the metering device  10  comprises voltage terminals  20 ,  22 , and  24 , current terminals  20 ′,  22 ′, and  24 ′. Further, a region  80 , which is between terminals  20  and  20 ′ is red, a region  90  between the terminals  22  and  22 ′ is blue, and a region  100  between the terminals  24  and  24 ′ yellow. Understandably, these colors are given only as an example and can vary.  
         [0019]     Accordingly, during installation the wires pairs  50  and  50 ′,  60  and  60 ′, and  70  and  70 ′, from the loads  30 ,  35  and  40 , respectively, are connected to the matching voltage and current terminal pairs  20  and  20 ′,  22  and  22 ′,  24  and  24 ′, respectively. Further, this is easily accomplished as wires pair  50  and  50 ′ and the corresponding terminal pair  20  and  20 ′, which are identified by area  80 , are red, wires pair  60  and  60 ′ and the corresponding terminal pair  22  and  22 ′, which are identified by area  90 , are blue, and wires pair  70  and  70 ′ and the corresponding terminal pair  24  and  24 ′, which are identified by area  100 , are yellow.  
         [0020]     Accordingly, the present invention provides a system and method, which uses color-coding to identify wire pairs and their respective terminals in order to facilitate installation and prevent metering errors caused by crossing wire pairs.  
         [0021]     While the present invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details, may be made therein without departing from the spirit and scope of the present invention. For example, the present invention, although illustrated with three loads and different wire pairs can be applied to any number of loads and wire pairs. Further, the number of wire associated with each load may also vary.