IMPROVEMENTS IN THE MEASURE- MENT OF ELECTRICITY IN DISTRIBUTION SYSTEMS
Year: 1881

page_text: LETTERS PATENT to Edward Griffith Brewer, of 33, Chancery Lane, in the
County of Middlesex, for an Invention of "IMPROVEMENTS IN THE MEASURE-
MENT OF ELECTRICITY IN DISTRIBUTION SYSTEMS." A cominunication from
abroad by Thomas Alva Edison, of Menlo Park, in the State of New Jersey,
United States of America.
PROVISIONAL SPECIFICATION left by the said Edward Griffith Brewer at
the Office of the Commissioners of Patents on the 19th October 1881.
EDWARD GRIFFITH BREWER, of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS JN THE MEASUREMENT OF ELECTRICITY IN DISTRIBUTION
SYSTEMS." (A communication from abroad by Thomas Alva Edison, of Menlo
Park, in the State of New Jersey, United States of America.)
The object of this Invention is to produce method and means for determining
the aggregate consumption of electricity in a distribution system from the central
station where no individual meters are employed, or for ascertaining at the central
station the correctness of the total consumption shown by all the house meters, so
as to furnish data for comparison with the meter accounts, and further at the
same time to determine the amount of leakage in order that the cause of any
unusual waste of energy by leakage can be investigated and removed.
This is accomplished by arranging at the central station of the system or point
of generation a meter or meters for the measurement of electric currents which
will give the total current generated by the dynamo or magneto electric machines
and thrown into the main or consumption circuit, and also a meter for recording
the total leakage throughout the system, the difference between the former and
latter representing the total amount of the electricity used by the consumers.
These meters can be of any efficient construction, the electro-plating or depositing
cell meters being preferred.
The meter or meters for measuring the current generated by the dynamo or
magneto electric machines can be arranged in any one of three ways. A single or

page_text: double meter could be located in a shunt from the derived or multiple arc circuit of
each machine between the positive pole of the machine and the positive main
feeding conductor, or a single or double meter could be placed in a shunt from the
positive main feeding conductor between the machine or machines and the branch
conductors, or a meter (either single or double) could be arranged in a shunt from
the positive conductor of each branch or consumption circuit. In any case this
meter or these meters would be at the central station or point of generation, and
would indicate the total current thrown into the consumption circuit by the
generators, only a portion of the current however being shunted through the
meters, as will be readily understood.
The meter for measuring leakage is in a line from ground to the return or
negative main feeding conductor, the leakage of the system producing the flow of
an equal current from the ground to the generatora.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Edward Griffith Brewer in the Great Seal Patent Office on the
19th April 1882.
EDWARD GRIFFITH BREWER, of 33, Chancery Lane, in the County of Middlesex.
"IMPROVEMENTS IN THE MEASUREMENT OF ELECTRICITY IN DISTRIBUTION
SYSTEMS." A communication from abroad by Thomas Alva Edison, of Menlo
Park, in the State of New Jersey, United States of America.
The object of this Invention is to produce method and means for determining the
aggregate consumption of electricity in a distribution system from the central
station where no individual meters are employed, or for ascertaining at the central
station the correctness of the total consumption shown by all the house meters, so
as to furnish data for comparison with the meter accounts, and further at the same
time to determine the amount of leakage in order that the cause of any unusual
waste of energy by leakage can be investigated and removed.
This is accomplished by arranging at the central station of the system or point of
generation a meter or meters for the measurement of electric currents which will
give the total current generated by the dynamo or magneto electric machines and
thrown into the main or consumption circuit, and also a meter for recording the
total leakage throughout the system, the difference between the former and latter
representing the total amount of electricity used by the consumers.
These meters can be of any efficient construction, the electro-plating or depositing
cell meters being preferred.
The meter or meters for measuring the current generated by the dynamo or
magneto electric machines can be arranged in any one of three ways. A single or
double meter could be located in a shunt from the derived or multiple arc circuit
of each machine between the positive pole of the machine and the positive main
feeding conductor, or a single or double meter could be placed in a shunt from the
positive main feeding conductor between the machine or machines and the branch
conductors, or a meter (either single or double) could be arranged in a shunt from
the positive conductor of each branch or consumption circuit. In any case this
meter or these meters would be at the central station or point of generation, and
would indicate the total current thrown into the consumption circuit by the
generators, only a portion of the current however being shunted through the meters,
as will be readily understood.
The meter for measuring leakage is in a line from ground to the return or
negative main feeding conductor, the leakage of the system producing the flow of
an equal current from the ground to the generators.
In the Drawing Figures 1, 2, and 3 are diagrammatic views of the different
ways in which the station meters can be arranged.
1, 2, are the main feeding conductors, and 3, 4, 5, 6, 7, 8, the branch or
consumption circuits. From the latter extend the house conductors 9, 10, connected
in multiple are with the branch or consumption circuits, and in derived circuits
from 9, 10, are arranged the lamps L or other translating devices. G represents
the electrical generators which are dynamo or magneto electric machines connected
in multiple arc with 1, 2; M, M, (Figure 1), are the current meters arranged in
shunts between G and 1.
These meters can be replaced by meters M (Figure 2) in shunts of the positive
conductors 3, 5, and 7 of the branch or consumption circuits. A resistance R is
employed to shunt a definite proportion of the current through the meters; M³ is
the leakage meter in line 11 from earth E to 2.

page_text: All these meters M, M¹, M³, and M³, are station meters, and the total con-
sumption of the system is determined from them by the difference between
M, M', or M and M³. If the system were used for supplying a single customer,
these meters only would be required, but in general distribution system each house
circuit has a separate meter M so as to measure the electricity at the points of
consumption. The certainty with which the leakage of the entire system can be
determined at the source of supply, and consequently the total actual comsumption,
is a feature of advantage that this electrical distribution system possesses over
systems for the distribution of gas and water.
What is claimed is,―
First. In an electrical distribution system a meter or meters located at a central
station or point of generation for measuring the current generated, substantially
as set forth.
Second. In an electrical distribution system the combination of a current meter
or meters and a leakage meter located at the central station or point of generation
for determining the total actual consumption for the entire system, substantially as
set forth.
Third. In an electrical distribution system the combination of a current meter or
meters at the central station or point of generation and meters at the points of
consumption, substantially as set forth.
Fourth. In an electrical distribution system the combination of current and
leakage meters at the central station or point of generation and meters at the point
of consumption, substantially as set forth.
Fifth. In the art of distributing electricity for translation into light and power
the method of electrical measurement, consisting in measuring the current at the
points of consumption and in measuring the total actual consumption at the point
of generation, substantially as set forth.
In witness whereof, I, the said Edward Griffith Brewer, have hereunto set my
hand and seal, this Eighteenth day of April, in the year of our Lord
One thousand eight hundred and eighty two.