A SAFETY APPARATUS FOR USE IN THE HIGH TENSION SYSTEM OF ELECTRIC LIGHTING
Year: 1884

page_text: ARTHUR WRIGHT Electrical Engineer The Electric Light Works North Road
Brighton Sussex do hereby declare the nature of my invention for A SAFETY
APPARATUS FOR USE IN THE HIGH TENSION SYSTEM OF ELECTRIC LIGHTING to be
as follows:-
An instrument to be used in the high tension system of incandescent electric
lighting i.e where a number of parallels of lamps are placed in series with one
another. Each parallel being provided with such an instrument which automatically
effects the whole or some of the following objects.
1st The putting a special kind of reserve lamp (hereinafter called the safety
lamp) or two ordinary lamps in the circuit of the parallel to which the instrument
belongs, should any of the regular lamps in that parallel break.
2nd The rendering of the parallel in which one of the regular lamps have become
bruken and the safety lamp alight, less likely to have any more lamps break; by
the safety lamp being mide of such a nature as to be capable of absorbing much
more current than the regular lamps or by any other method of making the
current passing through each of the regular lamps in this parallel less than in those
in the others, such as putting in circuit two ordinary lamps as safety ones.
3rd The short circuiting the parallel should more than one or any desired number
of lamps break; with the object of preventing more lamps breaking, or the whole
circuit being broken by all the parallel's lamps breaking.
4th The metering of the amount of electrical energy used up in the parallel in a
given time.
5th The indicating on a scale the Electromotive Force of the lamps in the
parallel.
Each instrument may also have a hand switch by which the parallel may be
turned off independently of the others.
The following are some of the means by which the above objects may be
effected.
An electro-magnet or solenoid, wound with fine wire so connected as to form a
shunt of high resistance across the main leads of the parallel.
[Price 4d.]

page_text: In the circuit of this shunt may be placed a small depositing cell, for the purpose
of measuring how much electricity has passed through the shunt in a given time,
this being a measure of the amount of energy that has passed through the parallel
in that time.
The magnet has an armature, adjusted by a screw hereinafter called the
EMF screw, enabling it to be set at different distances from the magnet's pole,
according as the lamps in the parallel are of high or low E M F. and thus the
normal position of the armature (i e resting on the screw) may indicate on a scale
the E M F of the lamps.
The armature is so adjusted as to remain in its normal position until any of the
regular lamps in the parallel breaking, causes more current to pass round the
magnet which thereupon pulls the armature away from the EM F screw and
make contact with a spring, connected to one terminal of the parallel's safety lamp
(made as above described) the other terminal being connected to one main lead
and the armature to the other main lead. In this manner the safety lamp or
lamps are added to the parallel.
On any more lamps in the parallel breaking, the consequent increase in the
shunt magnet's power pulls the armature still nearer the pole until it makes
contact with another contact piece; this latter is joined up to one of the parallel's
main leads and the armature to the other, the parallel is thus short circuited on
the two touching and in this position they are kept by a mechanical catch or an
electromagnet through which the main current is made to pass and they cannot be
separated until the parallel is turned off by the hand switch or the broken lamps
replaced by new ones.
Instead of one shunt magnet as above described, two may be used, one for
putting in the safety lamps and the other for short circuiting the parallel.
Dated this 94th day of Data 1991

page_text: A Safety Apparatus for Use in the High Tension System of
Electric Lighting.
I, ARTHUR WRIGHT (Electrical Engineer) Regent Foundry North Road Brighton
Sussex do hereby declare the nature of my invention for A SAFETY APPARATUS FOR
USE IN THE HIGH TENSION SYSTEM OF ELECTRIC LIGHTING and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :—
An instrument to be used in the high tension system of Electric Lighting where
a number of parallels of incandescent lamps are placed in series with one another,
each parallel being generally provided with such an instrument (although one
night be made to act for several parallels) which automatically effects the whole
or some of the following objects.
1st The putting in a special kind of reserve lamp (hereinafter called the safety
lamp) or two or more of the regular lamps in the circuit of the parallel to which
the instrument belongs, should any of the regular lamps in that parallel break.
2nd The rendering of the parallel in which one of the regular lamps have become
broken and the safety lamp alight, less likely to have any moro lamps break by
the safety lamp being made of such a nature as to be capable of absorbing much
more current than the regular lamps, or by any other method method of making
the current passing through each of the regular lamps in the parallel less than in
those of the others, such as putting in circuit two ordinary lamps as safety ones.
3rdy The short circuiting the parallel automatically should more than one or any
desired number of lamps break with the object of preventing more lamps breaking
or the whole circuit being broken by the whole of the lamps in the parallel
breaking.
4thly The metering of the amount of electrical energy used up in the parallel in
a given time or in any desired number of parallels.
5thly The indicating on a scale the EMF of the lamps in the parallel.
Each instrument may also have a band switch by which the parallel may be
turned off and on independently of the others.
The following are some of the means by which the above objects may be
effected.
An electromagnet or solenoid, wound with fine wire so connected as to form a
shunt of high resistance across the main leads of the parallel.
In the circuit of this shunt may be placed a depositing cell for the purpose of
measuring how much electricity has passed through the shunt in a given time, this
being a measure of the amount of energy that has passed through the parallel
where each parallel has an instrument & meter, or the amount used up in the
parallels where one instrument acts on several parallels.
The magnet has an armature adjusted by a screw, hereinafter called the
EMF screw, enabling it to be set at different distances from the magneta pole
according as the lamps in the parallels are of high or low E M F and thus the
normal position of the armature (i.e resting on the screw) may indicate on a scale
the EMF of the lamps.

page_text: The armature is adjusted so as to remain in its normal position, until any of the
regular lamps in the parallel breaking causes more current to pass round the
magnet which thereupon pulls the armature away from the EMF screw and make
contact with a spring connected with one terminal of the parallel's safety lamp
(made as above described) the other terminal being connected to one main lead of
the parallel and the armature to the other main lead.
In this manner the safety lamp or lamps are added to the parallel and lighted so
as to give warning.
On any more lamps in the parallel breaking, the consequent increase in the
shunt magnet's power pulls the armature still nearer the pole piece, until it makes
contact with another contact piece. This latter being joined up to one of the
parallel's main leads and the armature to the other, the parallel is thus short
circuited on the two touching and in this position they are kept by a mechanical
catch or an electro magnet through which the main current is then made to pass
and they cannot be separated until the parallel is turned off by the hand switch or
the broken lamps replaced by new ones.
Instead of one shunt magnet as above described two may be used one for putting
in the safety lamps and the other for short circuiting the parallel.
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
1st The invention of an apparatus which renders the running of a series of small
parallels of incandescent lamps perfectly safe and free from any chance of a break
in the circuit, by a whole parallel of lamps breaking and from the chance of more
than one or two lamps in a parallel breaking, the first being effected by the
instrument short circuiting the parallel before many of the lamps have become
broken and the second by the instrument lighting up the safety lamps to replace
the broken regular lamps.
2nd The rendering of a parallel in which one lamp has become broken less likely
to have any more break by making the safety lamp or lamps (put in by the
instrument) absorb more current than the regular lamps, thus making the current
passing through the regular lamps less than when the safety lamp is not alight
and the full number of regular lamps in the parallel are alight.
3rdly The above method of measuring the amount of electrical energy used by a
parallel or parallels in a given time by passing the current which flows through a
high resistance shunt on a parallel or parallels through a depositing cell whose
plates can be periodically weighed Or briefly the application of a depositing cell
for the determination of the consumption of electrical energy to the high tension
system of clectric Lighting by inserting it in the circuit of a high resistance shunt
on the parallel or parallels to be metered.
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T