Portable programmer-reader unit for programmable time registering electric energy meters

A portable programmer-reader unit for transferring and monitoring replaceable meter program control data utilized by a programmable time registering AC electric energy meter type including a transducer producing pulse signals related to an electric energy quantity to be measured, a clock producing real time data, a memory containing program control data having predetermined coded formats, said program control data including constant data items representative of metering rates and variable data items representative of real time categories, a meter sequence controller comparing said real time data to said variable data items and selecting a constant data item in response to said comparison, said metering sequence controller accumulating said pulse signals in response to said selected constant data item, and an external data communications interface responsive to said sequence controller, said portable programmer-reader unit comprising:

• first, second and third memory means each having memory locatons for storing identical kinds of data items;
• means generating reference time and calendar date data in a format corresponding to the format of corresponding time and calendar date data items of said meter program control data;
• means for transferring said reference time and date data to the memory locations of said first memory means for storing reference time and date data items;
• means for effecting bidirectional data communications with said external data communications interface of said meter, said communications including a first data transfer of the coded contents of the data items of said program control data in said meter including a current time data item, and old security code data item and a new security code data item to the corresponding data item memory locations of said second memory means, a second data transfer to said meter so as to replace a coded current time data item of said program control data in said meter with the coded contents of the reference time data item memory location of said first memory means while leaving the new and old security code data items of said program control data unchanged, and a third data transfer of the reprogrammed time data item and a changed old security code data item and a changed new security code data item of said program control data to said third memory means, wherein said changed old security code data item is said new security code data item;
• means for displaying said changed old security code data item for comparison with a prior new security code data item, said comparison revealing unauthorized programming, said means displaying said changed new security code data item for future comparisons;
• means for comparing the received coded time data items in both of said second and said third memory means with the reference time data item produced by said means generating said reference real time data;
• and
• error indicating means responsive to the comparing means when said received data item is different by more than a predetermined time value from the reference time data item.

A programmer-reader unit for a programmable time registering AC electric energy meter including a transducer producing pulse signals related to an electric energy quantity to be measured, a clock producing real time data, a memory containing program control data having predetermined coded formats, said program control data including constant data items representative of metering rates and variable data items representative of real time categories, a meter sequence controller comparing said real time data to said variable data items and selecting a constant data item in response to said comparison, said metering sequence controller accumulating said pulse signals in response to said selected constant data item, and an external data communications interface responsive to said sequence controller, said programmer-reader unit comprising:

• sequence controller means including logic circuit means and input and outputs for receiving and transmitting binary logic signals;
• timer circuit means for generating regularly occurring timing signals to said sequence controller means;
• read-write addressable memory means connected with said sequence controller and including first and second memory areas having mutually identical memory locations wherein said first memory area stores meter programming input data transferrable to said meter and said second memory area stores memory output data receivable from said meter, each of said mutually identical memory locations of both of said memory areas storing identical kinds of data items, each kind corresponding to a separate data item included in said program control data utilized by said meter, and each of said identical memory locations of both of the memory areas storing said data items thereof in identical orders of sequentially arranged memory locations each being in the same order as the order of said data items of said program control data when utilized by said meter, whereby said first and second memory areas form data images of said program control data of said meter;
• said read-write addressable memory means further including a further memory area storing reference real time and date data in response to said timing signals applied to said sequence controller means;
• means identifying predetermined ones of said data items of said program control data having corresponding memory locations in both of said first and second memory areas by separate numerical display identification numbers arranged in numerically sequential order;
• display means including a plurality of visual readout elements responsive to said sequence controller means for producing, for a predetermined maximum time period, numerical readouts of both said display identification number and the numerical value of a data item designated by said identification number;
• manually operable display sequence control means for incrementally changing the sequence of producing visual readouts of said data items designated by a corresponding identification number in accordance with the numerical sequence of said identification numbers;
• bidirectional communication interface means for communicating with said external data communications interface of said meter, said communications including the transfer of the coded values of the data items of said program control data from said meter to said second memory area of said read-write memory means and the transfer of the coded values from said memory locations of said first memory area to said program control data utilized by said meter;
• power supply means including a critical load supply line connected with said timer circuit and said read-write memory means and a non-critical load supply line connected to higher power consuming circuits of said programmer reader unit including said sequence controller means, and further including a battery for continuously energizing said critical load supply line and selectively energizing said non-critical load supply line;
• and
• power on logic circuit means for initiating logic signals to said power supply means to effect selective energization of said non-critical load supply line in response to either said timing signals or actuation of said display sequence control means.