Note: Descriptions are shown in the official language in which they were submitted.
CA 02460828 2004-03-03
-2-
ARCING FAULT TROUBLESHOOTING INSTRUMENT AND METHOD
THEREFORE
This invention provides a novel instrument and method of its use that provides
troubleshooting
assistance for locating loose connections or shorting conductors that are
passing a nominal current
being fed to a resistive, inductive or capacitive load. The said invention
also provides preventative
maintenance of existing 11 S-220 volt alternating current or direct current
low voltage electrical
systems by exposing said loose or shorting conductors early in their life
cycle before they become
hazards. More particularly an interactive portable battery operated arc fault
detector that in one
embodiment utilizes a hammer shaped member that is swung as a standard claw
hammer would be to
supply mechanical vibrations that are integral to the operation of the present
inventian. Also in
another embodiment the use of a vibrator serves as the source of vibrations.
The said mechanical
vibrations thereby elicit arcs from loose or shorting conductors all without
the need to remove switch
or receptacle plates or to open ceiling fixtures. More specifically the
detection of hidden electrical
hazards. A great need exists specifically for homes built between 1965 and
1973 when aluminum
wire was commonly used. As stated in a U. S. consumer product safety
commission publication
numbered 516,aluminum wired homes of the said time period are 55 times more
likely to have one or
more connections reach fire hazard conditions. Also noted in the publication
is the statement
" unfortunately not all failing aluminum wired connections provide warning
signs such as warm to
the touch face plates, flickering lights, circuits that are not working or the
smell of burning plastic".
Aluminum wired connections have been reported to fail without prior
indications. The present
invention is capable of detecting such hazards in their infancy.
BACKGROUND OF THE INVENTION
Existing arc fault safety devices are usually manufactured in the form of a
circuit breaker and reside
in a distribution panel ar in a duplex receptacle. In response to arc faults
in the circuit that an arc
fault circuit interrupter in the form of a breaker or a duplex outlet is
protecting a tripping of the said
breaker or receptacles power ensues. In one patent it was observed that an
inventor and his company
patented such above-mentioned devices but also and of particular interest is
the said companies
CA 02460828 2004-03-03
-3-
development of an arc fault monitor that plugs into an outlet. Its function is
to monitor the 115-volt
64-cycle sine wave characteristics and if an arcs signature were to be
detected an alarm would sound.
The said patent is that of blades-2125026. Other examples of arc fault circuit
breakers are:
5121282 issued to White 4951170 issued to From
4639817 issued to Cooper 5938246 issued to Durivage
6266219 issued to Macbeth
Though the above arc fault circuit interrupters serve a valuable function and
blades monitor is a
useful device, they are passive not interactive, and none are battery powered
as is the present
invention. Accordingly there has been a continuing need for improvement.
SUMMARY OF THE INVE1~TTIOIV
The present invention pertains to the detection of hidden arcing faults in
electrical systems. Although
the present invention can detect arcs from direct current sources it is
believed a more suited
application would be furl 15/220-volt apparatus and wiring in residential
homes and apartments,
some convnercial and industrial applications would apply as well. Electrical
arcing represents a
severe threat that can and does result in loss of life and property. There are
various causes of such
electrical hazards some examples being diminished spring tension on circuit
breakers or receptacles,
shorting electrical conductors to each other or to ground and loose
terminations on electrical
apparatus. Also, as mentioned, aluminum wiring is a hazard therefore houses
with aluminum wiring
are particularly amenable to loose connections. The aluminum wire corrodes and
when mixed with
copper without special care their different expansion coefficients pose a
problem. Wires that were
cut or nicked when installed are also hazards. Many reasons for the presence
of electrical wiring
faults occur. The results are line arcing or contact arcing. Line arcing could
be a short to ground or
from one conductor impacting another conductor of a different phase. Contact
arcing could be a
loose screw connection on a light switch or a receptacle or the improper use
of wire connectors. If a
condition degrades to the point where a conductor burns through, a resistive
connection may remain
and small vibrations may bridge the gap temporarily thereby creating an
electric arc if a current flow
CA 02460828 2004-03-03
-q.~
is present such as a light or a plug in load. The present inventions
electronic circuit would alarm to
such arcs. Even loose light bulbs although not particularly hazardous can
diminish the life cycle of
such a light and the arcing can cause dust to catch on fire. The present
invention can be used in a
troubleshooting mode for such faults or as a preventative maintenance check
for electrical systems by
looking for loose or shorting connections that have not yet degraded to the
point of being dangerous.
It is more beneficial o correct wiring faults early in their life cycle. It is
believed that some people
usually are not aware that an arcing fault exists. As an example a light
switch that has an arcing fault
may show symptoms in the form of a temporary dimming of the light associated
with the said switch.
Dimming of lights occurs in many instances due to a fridge compressor starting
or a fiunace fan
starting, both of which have a high inrush current so homeowners are
desensitized to the dimming of
lights. Present safety devices detect such faults and interrupt the power that
feeds the said fault. This
type of system is not readily available to average homeowners due to the cost
of such safety devices.
Also the electric code dictates their usage in newer built homes and needed
only in the bedrooms.
Also the said safety devices can be prone to false triggering and if a fault
is present it still needs to be .
located. The present invention and associated vibration testing procedure
locates faults as it performs
the said preventative maintenance on electrical apparatus and wiring. The term
preventative
maintenance is not normally equated with wiring systems but preventing
electrical fires and unstable
voltages is a great benefit. Unstable voltage and current are also a result of
arcing electrical faults
and can degrade equipment connected to such a source of unstable power. The
present invention
addresses the problem of arc faults in a unique manner. The present inventor
has offered two
embodiments but one commonality is the use of vibrations utilized in
conjunction with the use of the
present inventions electronics. The said vibrations elicit arcs from loose or
shorting conductors
whose electromagnetic signature is amplified by an electronic circuit that
responds to arcs of varying
frequencies and results in a visual and auditory alarm. It is believed that
electrical connections that
axe intermittently loose or shorting, when subjected to mechanical vibrations,
will make and break
the connection thereby eliciting an arc if a current flow were present. An arc
may be almost invisible
to the naked eye if the current flow is small but it has been found that even
a current in the milliamp
range will trigger the present inventions alarms if the said current flow is
broken then reconnected.
Used in conjunction with one embodiment of the present invention is a
procedure called the bang test
by the present inventor. The said bang test utilizes a hammer like member of
the present invention in
CA 02460828 2004-03-03
..
one embodiment that also has a fixed circular wound antenna in the head of the
said hammer like
member that is swung, with varying degrees of intensity, like a standard claw
hammer would be to
impact around building material such as drywall that is supporting electrical
apparatus such as light
switches, receptacles and fixtures thus the term, bang test. The said swinging
motion transfers
vibratory forces to the wiring of said switches, receptacles and fixtures
whereby loose or shorting
connections would belay their presence by eliciting an arc. If an arc is
forthcoming the said antenna
would be in close proximity to the source of the said arc and the present
inventions alarms would be
triggered. For a light switch, receptacle or fixture or any electrical
apparatus the hammer would
impact by repeated swinging of the said hammer all around the said apparatus.
In the case of the said
receptacle a load that requires a small amount of current would be plugged in.
~ffered as an adjunct
for the testing of receptacles is a dummy load that will be more closely
examined further into this
application. The said hammer has a padded surface on one end for the testing
of said lights and
receptacles and also for testing ceiling fixtures so as not to cause damage.
In a second embodiment
an electrical vibrator is used and this embodiment could be used for testing
distribution panels. If
when testing the said panel the present inventions alarms are triggered the
cover can then be
removed and an inspection of the connections would be done. It has been noted
through experience
that the source of arcing could be a circuit breaker itself. Some circuit
breakers have
pressure fitting contacts spring held to the buss line of the panel and the
spring tension may be
degraded for whatever reason and minute arcing between the tabs and the buss
bar may ensue.
Admittedly such arcing may seem insignificant but the voltage surges that
ensue could degrade
electronic equipment such as computers and even the life of a light bulb would
be reduced due to the
current instability. Also possible is the degradation of the contact surfaces
to the point where a
resistive barrier may form and heat would rise to the point of combustion.
Such said degradation is
highly dependent on the current draw ofthe Load. A circuit breaker feeding a
four-slice toaster for
example would be subject to a greater rate of degradation and produce a more
hazardous situation.
While working as an electronic electrician for twenty years in various
factories the present inventor
utilized the said bang test many times on circuit breaker distribution panels,
control panels, fuse
panels and motor starters and occasionally a spark could be seen belaying the
presence of a loose or
shorting connection when mechanical vibrations from whatever means were
impinged upon said
electrical apparatus. The present invention is particularly advantageous in
that a visual representation
CA 02460828 2004-03-03
-6-
of an arc is not needed, this fact allows for the testing or troubleshooting
of distribution panels
receptacles and light switches having cover plates or ceiling fixtures whose
structures precludes a
visual investigation. Most arc faults are hidden but are easily detected
electronically because an arcs
electromagnetic signature travels through the air, on a conductor and even
metal barriers ai~ord a
path for the said electromagnetic signature. It should be noted that some
loose connections are not
yet to the point where degradation has occurred and spring tension may butt a
conductor in the said
connection sufficiently against a conductors termination that the vibratory
forces may not jostle the
said connection sufficiently to elicit an arc response. Such a situation has
not yet reached the danger
point. In time such said degradation of electrical connections will cause the
said connections to
become amenable to manipulation by mechanical vibrations due to a resistive
oxide forming or due to
the weakening of the spring tension due to heat. Some light switches have so
much dust internal to
the switch that just turning the light switch on and off will cause multiple
alarms from the present
invention. Such a switch could cause sputtering arcs and intense heat could
build up and result in a
fire. In such a case the switch should be changed. A test for the present
invention before use is to
hold the antenna of either embodiment close to a light switch and a user would
look for a clean single
alarm when the switch is turned on and off_ Admittedly the present invention
can locate minor
problems but that is the point of preventative maintenance specifically,
locating minor problems
before they become major problems. One key to the use of the present invention
and its associated
procedure is the repeatability of alarms. If when you perform a vibratory test
on any electrical
apparatus, for example a light switch, and you bang around the switch 8 times,
if an alarm from the
present inventions electronics is forthcoming every time you perform a
vibration test on said switch it
should be repeated a few times and if similar results occur then in elect
confirmation has been given
that a loose or shorting electrical conductor may be present and the cover
plate should be removed
and an inspection should ensue. The same applies to ceiling fixtures,
receptacles, distribution panels
or any electrical apparatus ac or do that has electrical conductors. On the
other hand if you were to
bang the said light switch and only one alarm is given then not repeated on
subsequent tests then it is
likely a burst of electromagnetic radiation from another source triggered the
alarm such as a nearby
fridge compressor kicking in. Other source of false fault alarm triggers would
be a 2 to 6 circuit
sputter. Such a splitter would have to be removed and a said dummy load put in
its place. A solid
connection between the receptacles contact blades and the load must he
insured. In one instance
CA 02460828 2004-03-03
while testing a receptacle, five bangs from the embodiment with a hammer like
member caused three
alarm triggers and could be repeated so I removed the cover plate and did a
visual inspection. It was
discovered that the receptacle had been tampered with by a non qualified
person hecause the
receptacles casing was cracked with a part missing and one of the internal
connection blades was
visible. Also there were severe scratches on the receptacles casing and there
was a I4-gauge wire
shunt joining two hot screw connections. In other words someone tried to
change a split duplex into
a standard duplex. It was determined that even though the receptacle was
functioning properly it was
a receptacle that the toaster was plugged into and I determined that it should
be changed.
Interestingly enough was the fact that when I tested the said receptacle I had
no load plugged into it.
One peculiar aspect of the present invention is that even unloaded loose
connections seem to trigger
the present inventions alarms but to be totally thorough a dummy load (Fig. 9
and I O} should be
placed in all receptacles of a residence under test and all lights should be
on due to the peculiarities
of apartment and residential parallel circuits. As an alternative to the said
dummy loads is a series of
one half watt neon lights connected to some 3 prong male plugs and some to a
two-wire plug (not
shown). When testing light switches the light itself is the load and can be
performed by anyone. In
one instance while testing a ceiling fixture every time I banged the fixture
an alarm ensued and when
I opened the fixture for a visual inspection I discovered a loose neutral
crimp. I turned down the
lights and when I hanged the suspect wire with the padded side of the
embodiment with the hammer
like member I noticed tiny arcs coming from the neutral screw crimp
termination. The surrounding
area had dirt and insulation so I changed the fixture. At best such a
situation can cause the light bulb
to burn out more often due to the unstable current flow and also possible is
nearby dust catching on
fire. In other instances the present inventions alarms were triggered by loose
wiring in a light switch
but no change in the lights brilliance was noticed. The present invention can
locate arcs that give no
visual response in the associated light under test but indeed are still
present. The testing of
receptacles may be better performed by contractors who could afford to acquire
30 odd dummy
loads (Fig. 9 and 10} that could be beneficially utilized. The need for such a
number of dummy loads
is cumbersome but it is felt that they would be needed. In some cases a
ceiling fixture is a power
source for a parallel run of some duplex outlets and when you perform a
vibration test on such a
fixture the associated duplexes should have loads plugged in to provide a
current flow from the lights
loose connection to the said receptacles. Ideally the present invention would
be better utilized for
CA 02460828 2004-03-03
empty houses or apartments. A vacant area would speed the testing procedure.
Another area that
would benefit from the usage of the present invention and its vibrator testing
is older homes and as
stated earlier homes with aluminum wiring. Some furniture and appliances may
have to be moved to
gain access to receptacles. Also an avenue of usage is in industrial and
commercial 115-220 volt
systems. The present invention and procedure of usage could suitably be
utilized as a franchisable
operation for the testing of buildings, apartments and residential units or
for older homes being
bought and sold and when tenants or owners vacate. Another possibility is
electrical inspectors
utilizing the said vibration testing through contractors who would be licensed
to perform such
vibration testing.
Other features and advantages of the present invention will become apparent
from the following
more detailed description taken in conjunction with the accompanying drawings
which illustrate by
way of example the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. lA Shows a schematic diagram of the present inventions electronic circuit
applicable to both
embodiments of the present invention.
Fig.lB shows an advantageous camponent layout ofthe present inventions
electronic components
Fig. 2 shows one embodiment of the present invention that utilizes an
electronic control box and is
tethered by a suitable conductor to a hammer shaped member that has inside it
a circularly wound
bxed antenna, said member would be used to supply mechanical vibrations
through a procedure
called the bang test to wiring systems and associated building materials
supporting electrical
apparatus.
Fig.3 shows a back view ofthe electronic control box 14 housing the circuit
referred to in Fig. lA.
Fig.4 shows and end view of the electronic control box 14.
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CA 02460828 2004-03-03
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Fig.S, 6 and 7 show different perspective views of the hammer like member
shown in figure 2.
Fig.8 shows another embodiment that utilizes a motorized vibrator tethered by
the antenna cable to
the electronic control box l4.Said vibrator having means to plug into a 115-
volt outlet.
Fig.9 shows a double receptacle dummy load for a 115-volt receptacle that can
be manufactured as
an adjunct to the present invention and would be utilized when testing
receptacles.
Fig. I O shows a single receptacle dummy load.
Fig. l l is a symbolic representation of a resistive element and neon light
that would be placed inside
the nonconductive pliable material of the dummy loads.
Fig. I2 and 13 shows stickmen representations using different embodiments of
the present invention
and their usage.
DETAILED DESCRIPTION OF THE INVENTION
Fig. l A is a schematic diagram of the electronic circuit used in both
embodiments of the present
invention. The power source is a 9-volt transistor type battery 1. An arcs
signal is picked up by the
antenna 2 and is sent to a 2-stage transistor preamplifier, 3 that amplifies
the said signal 200 times.
The output of the said preamplifier goes to an LM386 operational amplifier 4
where the arcs signal is
further amplified 200 times. The output of the said operational amplifier goes
to the input of a 4469
buffer inverter 5 and at this point is tied to a potentiometer 6A to alter the
bias threshold at the 4069
input thereby eliminating static background noise. The inverted amplified
signal is now sent to an
LM555 timer shaper 7 that lengthens the signal to an appropriate level for the
alarms to become
noticeable. The alarms are a high intensity light emitting diode 8 and a piezo
alarm 10 of su~cient
frequency and decibel level as well as being low current drain and used in the
present invention is an
Intervox BRP-1408-12-CS-+A.02 piezo alarm. If a piezo alarm is used that
requires more current
CA 02460828 2004-03-03
-10-
than the 555 can comfortably deliver, a 100-ohm limiting resistor 9 can be
used. This circuit offers a
level of immunity to high frequency noises such as fluorescent lights, dimmer
switches and
transformer 60-cycle hum and does not respond to the presence of a 115-volt
potential. The
potentiometer 6A is adjusted to compensate for ambient electromagnetic
radiation caused by the said
lights, switches, transformers and 60 cycle potential. The said potentiometer
adjusts the base line
threshold of the 4069. The switch 6B turns the circuit on and off: Also shown
are carefully chosen
resistors and capacitors that provide biasing, filtering and isolation
characteristics to the functioning
of the said electronic circuit.
Fig.lB shows an advantageous component layout. It was found that this
arrangement was necessary
to prevent a detrimental capacitive coupling between the present inventions
components. The circuit
is sensitive to component layout specifically a straight line layout is
preferable to a more compact
layout where say the transistors run parallel to the integrated circuits IC1,
IC2 and IC3.
Fig.2 shows a first embodiment and shown is control box 14 which houses the
electronic circuits
shown in Fig. l, said control box being tethered to the hammer type member of
the present invention
by the antenna cable 2 that is a single conductor of suitable durability and
gauge. The antenna cable 2
would be a continuous run thru the handle 17 terminating as secured circular
wraps spaced evenly in
the hammer 18 and secured to the said hammer member by 15. An on-off tuning
potentiometer
combination switch (6A-6B) provides fine-tuning of the electronic circuit
thereby compensating for
the electric noise of fluorescent lights, dimmer switches and 60 cycle
transformers. The holes 11
allow the sound from the piezo alarm to travel to a user. Light emitting diode
14 provides a visual
alarm. The electronic control box 14 is corned on a users belt by the belt
clip 12. When not in use the
hammer portion, particularly the retaining ring 16 is placed on the retaining
clip 13. The hammer
portion consists of the handle 17 and the striking surfaces 18 and 19. The
hammer 18 has a hard
plastic surface at one end for doing the bang test on more sturdy electrical
apparatus such as
electrical panels and a padded surface 19 at the other end for more delicate
apparatus such as around
receptacles, light switches and on ceiling fixtures.
Fig.3 is a hack view of control box 14 showing the belt clip 12 retaining clip
13 and cable connector
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CA 02460828 2004-03-03
-11-
115. Also shown is the light emitting diode 10 and the on off potentiometer
combination (6A-6B)
Fig.4 shows an end view of control box 14.
Fig.S, 6 and 7 are perspective views of the hammer portion shown in figure 2.
Shown are the threads
20 that join the handle 17 to the hammer portion 18,a padded surface 19 of
suitable material such as
leather is glued onto one end while the other end is hard plastic also of
suitable material such as
nylon. Also shown is the antenna cable support 15 and retaining ring 16. The
antenna 2, that is
secured in the handle so no movement occurs when the hang test is being
issued, runs through the
length of the handle 17 and culminates as a length of conductor wrapped in a
circular pattern with
equal spacing between the said conductor wraps in the hollow hammer 18. The
said antenna is also
affixed as previously mentioned to allow no movement between wraps when the
bang test is
performed because such movement would induce an electromotive force in the
conductor thereby
producing a minute burst of electromagnetic radiation that would set off the
present inventions
alarms. This fact is a testament to the sensitivity of the present inventions
ability to detect loose
electrical conductors. Also this arrangement allows the antenna to be close as
possible to the
electrical apparatus being checked.
Fig.8 shows another embodiment of the present invention that utilizes a
vibrator as the source of
vibrations, consisting of the antenna cable support 15 the vibrator body 21
and a padded surface 22.
For illustration purposes only a combination on-off potentiometer speed pot
23, could be used in
conjunction with a silicon control rectifier (not shown) incorporated into the
vibrator to assist in
finding the resonance of a particular material or apparatus thereby achieving
a more eff cient means
of transferring vibrations to the wiring of the said electrical apparatus. The
power cord 24 and plug
25 would supply the vibrator with 115-volt power. The antenna would consist of
a length of wire
wound in a circular fashion inside the vibrator body and connect to the
electronic control box 14 via
conductor 2 that is also part of the antenna circuit. This arrangement in
order to function properly
would need an induction motor with no brushes so as not to cause false
triggering in the electronic
circuit. Also necessary is the securing of the antenna wire wraps that would
farm the antenna inside
the vibrator. This embodiment can be used around switch plates, receptacle
plates but not
recommended for use on sensitive ceiling fixtures. Another advantageous use of
this embodiment is
CA 02460828 2004-03-03
-12-
on distribution panels where more severe vibratory forces are needed to cause
loose or shorting
conductors to belay their presence. When used on said switch and receptacle
plates the padding 22
would protect drywall from damage. When used on the dummy loads there would be
no problem
because the said dummy loads having a flat surface and being of a durable
material would not be
affected by the vibrations.
Fig.9 and 10 illustrate plug in dummy loads that could be manufactured as an
adjunct to the present
invention to be used when doing vibration testing of receptacles. Shown in
Fig.9 is a plug in for
duplex receptacles having a retractable handle 27 a plastic body 26 capable of
tolerating said
vibrating means and the electrical blades 29 that plug into the receptacles.
Also shown is the
transparent plastic window 28 and behind said window is a 115-volt neon
indicating means 34. The
said retractable handle would facilitate the insertion and removal of the load
as well and would
provide a flat surface to be struck by the padded side 19 of the hammer
portion or 22 of the vibrator
that would facilitate the transfer of vibrations to reach the duplex wiring
more effciently. Also the
said dummy load, would have a nominal resistance Fig. l l-33 that would supply
a naminal wattage
and would be incorporated into the construction of the said dummy load and
would facilitate the
offering of a stronger current source for arcs elicited by the vibration
testing. A neon light 34 could
also be incorporated into the said dummy loads to signal a user that 115-volts
is present at the
receptacle. The dummy load of fig.10 is for single receptacles and has a
retractable handle 31 and the
plastic body 30.AIso shown are the electric blades 29. The dummy load of Fig.9
would have 2
resistive loads 33 and two neon lights 34 whereas the single dummy load of
Fig.10 would have 1
such resistive load and light. Duplex receptacles have many parallel circuits
therefore all duplexes
should have a dummy load and all lights of a home or apartment should be on
when utilizing the
present invention and the method of its usage. Such thorough necessities would
ensure all
connections are tested.
Fig.l 1 shows a nominal resistive load 33 and a neon light 34 that would be
encased in the plastic of
the dummy loads shown in Fig. 9 and 10 and would be connected to the
electrical blades 29 The
resistive element is shown as 33 and testing has shown that a 50 thousand ohms
resistor having a
current of 2.24 milliamps, which equates to 2.76 watts, is su~cient to trigger
the present inventions
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CA 02460828 2004-03-03
-13-
alarms at a distance of three feet. The said resistive loads would be an
integral part of the durable
plastic moldings 26 and 30. The nominal resistive element would better serve
to facilitate a stronger
arc signal when a loose or shorting conductors make and break its connection
in response to
mechanical vibrations impinged upon associated electrical appar atus. A
contractor checking an
empty apartment for an insurance company or a real estate firm could better
afford to have the said
dummy loads. In some instances when using the said dummy loads one might find
that the receptacle
contact blades may have lost their spring pressure and cause contact bounce
between the dummy
load male contacts and the receptacles female blades. Older homes having older
receptacles may be
prone to such problems. Such a situation would require the plugging in of a
standard light plug that
has two blades no ground and if the light plug feels loose in the receptacle
then the receptacle should
be changed and the vibration test repeated.
Fig.12 and 13 portrays stickmen representations utilizing different
embodiments of the present
invention in different situations. Although many variations and embodiments
can be used in different
circumstances an attempt to illustrate some examples are given. Starting with
Fig.12A the stickman
is using the embodiment of Fig 2 and is using the padded side of the hammer 19
to do the bang test
on a ceiling fixture 26. In the case of a light being checked the switched on
light bulb is the load. A
loose connection at the light switch or the light fixture would trigger the
alarms. A gloved hand
tapping the ceiling fixture 26 can also effectively be used on the said
fixture as long as the antenna of
the said embodiment is near the point of impact.
In Fig.12B a duplex receptacle 2'1 is being tested with the embodiment of
Fig.2.and in this case a
contractor would use the said dummy loads {Fig.9 and 10) to facilitate current
flow should a fault
occur. The said dummy loads could withstand being lightly banged or vibrated
during testing. The
padded side of the hammer portion 19 is being used while checking the said
receptacle.
Fig.12-C shows a stickman testing a light switch using the bang test with the
embodiment of Fig:2.
The stickman of C is testing a light switch 28 with the padded portion 19
being utilized because the
drywall and switch cover plate is relatively fragile. The said light switch
would be on.
CA 02460828 2004-03-03
-14-
Fig.12-D shows a stickman initially using the unpadded side of the hammer
shaped member on a
distribution panel 29 therefore a more firm swing of the hammer member could
be used on the panels
thicker metal structure and if any trigger of the present inventions alarms
occurred then the cover
should be removed and the padded side 19 of the hammer shaped member would be
used to tap the
panels conductors and breakers or fuses. The vibrator embodiment of Fig. 8
would be more
appropriate for testing the said distribution panel. A specific frequency of
vibrations might have to be
established or a speed potentiometer utilized to achieve such an end. When
using the vibrator
embodiment of the present inventi~n the panel cover could stay on and should a
response be
forthcoming from the present inventions alarms then the cover removed and an
inspection would
ensue.
Fig.13E portrays a stickman utilizing the embodiment of Fig.B and is testing a
light switch 28
on a concrete block wall The said embodiment would have the circuitry of Fig.
lA so a visual and
auditory alarm would be given. The vibrator 21 has padding 22 so as not to
damage the switch cover
plate. The vibrator would plug into a 115-volt outlet.
