Improvements in and relating to Recording Electric Meters.
Year: 1891

page_text: Date of Application, 23rd May, 1891
Complete Specification Left, 2ûth Feb., 1892-Accepted, 9th Apr., 1992
PROVISIONAL SPECIFICATION.
Improvements in and relating to Recording Electric Meters.
1, GUGLIELMO MENGARINI, of No. 109 Piazza St. Bernardo, in the City of
Rome, Italy, Professor of Electrotecnic, do hereby declare the nature of this
invention to be as follows:-
-
This invention has for its object improvements in and relating to recording
electric meters.
The apparatus contains a coil of a suitable number of convolutions. This coil is
usually in two or more sections. Within this coil another coil is suspended from
above by two wires and a third wire descends from the coil to a point of attachment
below. Means are provided for regulating the tension of these wires. The
suspended coil is of a suitable wire and it is in circuit with a suitably adjusted
resistance. When the instrument is uninfluenced by current the suspended coil
stands with the plane of its convolutions crossing at right angles the convolutions
of the outer coil. When a current passes through the coils the suspended coil is
deflected from this position. On the suspended coil is an arm and this arm operates
to move a long horizontal index around an axis. The index carries a pen which
The drum is slowly rotated by
traces a line upon paper lapped around a drum.
clockwork whilst the pen is moved by the coil in a direction at right angles to the
axis of the drun.
These instruments have very little, in fact, quite an inappreciable self induction
and no mutual induction and consequently are well suited for continuous,
interrupted and alternating currents of either sinusoidal form or of any variation
between current, or potential and time.
These instruments are therefore very useful in central stations where the dynamos
are of different types and where the load is continually changing. The instruments
contain no iron, the action is entirely electrodynamical and registers with precision
the smallest variations of current or energy. The magnetic field in which the
suspended coil moves is of uniform and constant strength. The force deflecting
this suspended coil is in every position proportional to the sine of the angle of
deflection. Also the controlling force varies with the sine of the angle of deflection.
Equal increase or decrease of deflections corresponds to equal increase or decrease
of potential difference, current or energy. Hence it is possible to measure the
energy given by the diagrams of the instruments by an ordinary planimeter.
As these instruments depend on electrodynamical action, they cannot be
disturbed by any external influences.
Notwithstanding the force required to move the pen, the wasted energy
little.
very
Recording Voltmeters are constructed to measure to 100 volts but if required to
measure higher differences of potential it is only necessary to put in series with
them a non-inductive resistance.
Watt meters are constructed to measure the energy expended in circuits of
50 volts and if more is required the arrangement will be as the diagram Figure 1
shows. A a dynamo, continuous or alternating of any description, 50 volts at the
terminals of the dynamo. B and C mains, D lamps, EE fixed circuit, coil or frame
of Watt meter, F moveable coil with bifular suspension. The current is taken
A non-
from the movable coil at terminal G of fixed coil and at H of main.
inductive resistance R is inserted in suspended coil-circuit. The resistance
of RF, riz. of the whole shunt-circuit is, 'say, 300 Ohms at 20° C. To use the

page_text: Watt meter at any other potential difference at the terminals of dynamos a
resistance has to be added to R. For example if it has to be employed with a
dynamo of 1000 volts potential difference at the terminals, to R must be added
a non-inductive resistance of 5700 Ohms.
When transformers are employed, the suspended coil may be connected to any
terminals of the transformers, while the mains are joined to the other terminals of
transformer T as is indicated in Figure 2. The letters of Figure 2 correspond to
those of Figure 1.
The Watt meters are not only suitable to measure the total amount of energy in
installations of simple circuits for current distribution, but also for three, four or
more wire systems. For the three wire system, the connections are as follows:-
The total number of turns in the fixed coil are divided into two parts. Their
terminals are connected in such a way that the currents will flow in both circuits
in same direction. See Figure 3A and A' dynamos, connected in series. B, C
and D mains, KK lamps, fed by B and D, D and C, B and C. E E terminals of
the first circuit of the recording electric meter. EE, those of the second.
Also in the three wire system-the general connections may be as follows:-
The fixed coil divided into two sections, one having half the number of turns of
the other and connected so that the current flows in them in opposite direction.
See Figure 4 A A' dynamos in series, B, D and C mains, E E terminals of the first
section of the fixed coil of the Watt meter, E' E' second section.
The suspended coil, which is not shewn, can be shunted either with B D or DC.
In the four wire system the general connections may be as follows:-
The fixed coil has to be divided into three circuits, the number of turns being
in each on the ratio 32: 1. The connections have to be made so that the current
Hows in sections 2 and 1 in opposite direction to section 3. See Figure 5 A A' A"
dynamos in series, B C D D mains. KK lamps fed by any pair of mains.
EE terminals of the first section of fixed coil of the Watt meter, E E' terminals of
the second and E" E" terminals of the third section.
A
The suspended coil can be shunted either to BD, DD' or D' C. In the
described way the Watt meter can be arranged for any number of wires.
Watt meter made for several wires can be also used for two wires.
Dated this 23rd day of May 1891.
CARPMAEL & Co.,
Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in and relating to Recording Electric Meters.
I, GUGLIELMO MENGARINI, of No. 109 Piazza St. Bernardo, in the City of
Rome, Italy, Professor of Electrotecnic, do hereby declare the nature of this
invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention has for its object improvements in and relating to recording
electric meters.
The apparatus contains a coil of a suitable number of convolutions. This coil is
usually in two or more sections. Within this coil another coil is suspended from
above by two wires and a third wire descends from the coil to a point of attachment
below. Means are provided for regulating the tension of these wires. The
suspended coil is of a suitable wire and it is in circuit with a suitably adjusted
resistance. When the instrument is uninfluenced by current the suspended coil
stands with the plane of its convolutions crossing at right angles the convolutions
of the outer coil. When a current passes through the coils the suspended coil
is deflected from this position. On the suspended coil is an arm and this arm

page_text: The index carries a
The drum is slowly
operates to move a long horizontal index around an axis.
pen which traces a line upon paper lapped around a drum.
rotated by clockwork whilst the pen is moved by the coil in a direction at right
angles to the axis of the drum.
These instruments have very little, in fact, quite an inappreciable self induction
and no mutual induction and consequently are well suited for continuous interrupted
and alternating currents of either sinusoidal form or of any variation between
current, or potential and time.
These instruments are therefore very useful in central stations where the
dynamos are of different types and where the load is continually changing. The
instruments contain no iron, the action is entirely electrodynamical and registers
with precision the smallest variations of current or energy. The magnetic field
in which the suspended coil moves is of uniform and constant strength. The
force deffecting this suspended coil is in every position proportional to the sine
of the angle of deflection. Also the controlling force varies with the sine of
the angle of deflection. Equal increase or decrease of deflections corresponds to
equal increase or decrease of potential difference, current or energy. Hence it
is possible to measure the energy given by the diagrams of the instruments by
an ordinary planimeter.
As these instruments depend on electro-dynamical action, they cannot be
disturbed by any external influences.
,
Notwithstanding the force required to move the pen, the wasted energy is very
little.
Recording Voltmeters are constructed to measure to 100 volts but if required to
measure higher differences of potential it is only necessary to put in series with
them a non-inductive resistance.
Watt meters are constructed to measure the energy expended in circuits of
50 volts and if more is required the arrangement will be as the diagram Figure 1
slicws. A a dynamo, continuous or alternating of any description, 50 volts at the
terminals of the dynamo. B and C mains, D lamps, E E fixed circuit, coil or
frame of Watt meter, moveable coil with bifular suspension. The current is
taken from the movable coil at terminal G of fixed coil and at H of main.
A. non-
inductive resistance R is inserted in suspended coil-circuit. The resistance
of RF, viz. of the whole shunt circuit is, say, 300 Ohms at 20° C. To use the
Watt meter at any other potential difference at the terminals of dynamos a
resistance has to be added to R. For example if it has to be employed witli a
dynamo of 1000 volts potential difference at the terminals, to R must be added a
non-inductive resistance of 5700 Ohms.
When transformers are employed, the suspended coil may be connected to any
terminals of the transformers, while the mains are joined to the other terminals of
transformer T as is indicated in Figure 2. The letters of Figure 2 correspond to
those of Figure 1.
The Watt meters are not only suitable to measure the total amount of energy in
installations of simple circuits for current distribution, but also for three, four or
more wire systems. For the three wire system, the connections are as follows:-
The total number of turns in the fixed coil are divided into two parts. Their
terminals are connected in such a way that the currents will flow in both circuits
in same direction. See Figure 3 A and A' dynamos, connected in series. B, C
and D mains, K K lamps, fed by B and D, D and C, B and C. E E terminals
of the first circuit of the recording electric meter. E' E', those of the second.
Also in the three wire system, the general connections may be as follows:
The fixed coil divided into two sections, one having half the number of turns of
the other and connected so that the current flows in them in opposite direction.
See Figure 4 A A' dynamos in series, B, D and C mains, E E terminals of the
first section of the fixed coil of the Watt meter, E' E' second section.
The suspended coil, which is not shewn, can be shunted either with B D or D C.

page_text: In the four wire system the general connections may be as follows:
The fixed coil has to be divided into three circuits, the number of turns being in
each on the ratio 3: 2: 1. The connections have to be made so that the current
Hows in sections 2 and 1 in opposite direction to section 3. See Figure 5
A A A dynamos in series, B C D D' mains, KK lamps fed by any pair of
mains. E E terminals of the first section of fixed coil of the Watt meter.
E' E terminals of the second and E" E terminals of the third section.
The suspended coil can be shunted either to B D. D D or D' C. In the
described way the Watt meter can be arranged for any number of wires. A.
Watt meter made for several wires can be also used for two wires.
Figure 6 is a sectional elevation of a meter in accordance with my invention.
Figure 7 is a section on the line 7, 7 in Figure 6.
Figure 8 is a plan of the suspended frame upon which the inner coil is wound.
Figure 9 is an end elevation of the suspended frame.
Figure 10 is a plan of the stationary coils.
e
a a is a three legged standard erected upon a suitable base it carries by means
of the lugs a a¹ two stationary oblong coils made up of strips of copper b
rectangular in section and separated the one from the other and from the supporting
lugs by discs of insulating material. are bolts at the four corners which
clamp the coils together and to the lugs; these bolts pass through tubes which
may be of bone and which insulate the bolts from the strips b. are terminal
sockets upon the strips 6 to receive the electric leads. Obviously the two coils
may be coupled to operate as a single coil when required. is the frame upon
which the suspended coil is wound; the winding which is of fine silk covered wire
is at right angles to the stationary coils and it is partly shewn in Figures 6 and 7.
The ends of this winding, are lead out along the pins and then in loose spirals
to the insulated terminals d d upon the frame so as not to interfere appreciably
with the free movement of the frame c. is a small pulley on the frame around
which a suspending loop e of fine wire passes; the wire is led over the two grooved
pulley upon the capstan head. The ends of the suspending wire are wound
upon the pins which are clamped tight to the head by nuts at their lower
ends. The lower part of the capstan head is conical and fits a corresponding
recess a² at the top of the framework a.
From the underside of the frame c a single wire descends to the inverted capstan
head which is similar to except that provision is made for receiving one wire
only. The cone of this capstan head is held in a socket a² upon the framework in
which for the purpose of adjustment it can be turned.
is an arm projecting from the frame and carrying the spring finger with its
adjusting screw.
is a light steel blade or index mounted on an axis h¹ so that it can turn very
freely and it is counterpoised by a weight ². is a standard which carries the
axis ¹.
The spring finger enters a slot at * in the index so that the index partakes
of the movement of the suspended coil. The index h rests upon a stationary guide
rail and it carries a pen or pencil ³. is the drum mounted on the axis and
carrying the paper on which the pen or pencil h³ traces.
The drum is slowly revolved by clockwork the details of which it is unnecessary
to describe the clockwork may be contained within the drum. 11 are adjustable
stops which limit the swing of the frame c.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what I
claim is
1. A recording electric meter consisting of a stationary coil: another coil
suspended therein; a paper drum driven by clockwork, and a pen moving with
the suspended coil and producing a trace upon the surface of the paper drum.

page_text: 2. A recording electric meter consisting of two or more stationary coils with
separate circuit connections; another coil suspended therein, a paper drum driven
by clockwork and a pen moving with the suspended coil and producing a trace
upon the surface of the paper drum.
3. A recording electric meter substantially as described and represented by the
annexed drawings.
Dated this 15th day of Wah………… 100A
CARPMAEL & Co.,
Agents for the Applicant.