Field of the invention
[0001] The present invention relates to power cable clamps, for example to power cable clamp
arrangements adapted for making electrical connections to branch cables at arbitrary
points along lengths of a main power cable which is susceptible to being exposed to
wet and/or damp operating condition. Moreover, the present invention also concerns
methods for making power cable branches, and for methods of preparing cables for coupling
a branch cable to a main cable clamp arrangement. The main cable consists of individually
insulated and sheathed conductors with a specific lay-up length, whereas the branch
cable may be screened and may include a common sheath. Furthermore, the present invention
relates to kits for making connections to cables using the cable clamp.
Background of the invention
[0002] In many power-consuming electrical installations comprising multiple spatially separate
power consuming devices, for example lighting units disposed along a motorway, it
is desirable to couple the devices to a single length of cable for reducing installation
complexity and cost. An example of clamp system for making connections to a length
of cable comprising multiple current carrying conductors is described in a published
PCT patent application WO 99/66597 ("A T-joint Connector", Tappat Engineering Pty. Ltd., Australia). The system is adapted
for interconnecting with a power cable. The power cable includes an outer insulating
jacket encircling inner insulated sector conductors in mutually parallel disposition.
Moreover, the system includes a clamping unit for clamping around the cable. A series
of apertures are included in the apparatus. During installation, a cable cutting tool
of the system is inserted into one or more of the apertures for removing portions
of inner and outer insulating jackets of the cable spatially underneath the one or
more apertures. Subsequently, a connection unit of the apparatus is then inserted
into a corresponding aperture for piercing a corresponding inner conductor of the
cable. Moreover, the clamping unit has inwardly projecting ribs for locating between
edges of the inner insulated sector connectors for accurately aligning the one or
more apertures against the inner sector conductors. Optionally, the outer jacket of
the power cable is marked so as to indicate spatial orientation of the sector conductors
within the outer jacket.
[0003] In the German utility model
DE20004005435U1, a contact unit with axially movable electrical contact position, a spring loaded
contact (SLC) is presented. Although this contact arrangement is intended for HF contacts,
it may be used to advantage in LF high current applications as well. This utility
model does not discuss sealing of the contact from moisture.
[0004] As aforementioned, a single cable is often installed, for example, along a length
of a road or along a length of a tunnel, wherein electric power and/or signals are
to be distributed along the length to distribute energy and/or signals to various
devices along the length, for example to road lights or smoke fans. It is found in
practice that the single cable is often installed in locations which have difficult
access and/or are unsafe, for example within limited volumes. Moreover, there is a
contemporary trend to employ cables including conductors with increasingly larger
current-carrying conductor cross-sectional areas to cope with longer lengths and/or
to supply progressively greater power consuming devices. Making connections to these
contemporary cables is becoming increasingly difficult and time-consuming. A better
solution is thus desirable.
[0005] A further issue arising when making connections to aforementioned cables is that
they are typically operated at potentials of 110V, 230V, 400V, voltages in between
and also at elevated voltages above this, for example 1 kV or more, for reducing a
corresponding magnitude of current when supplying a total power consumed by the devices
coupled along the length of the cable. Operating at these elevated potentials when
the cable is exposed to wet and/or damp conditions requires that special care is taken
to avoid any risk of electrical flashover which could disrupt operation of the cable
along its entire length.
[0006] It is conventional practice that a single cable is installed along an entire length
of a given electrical installation, wherein the single cable is cut and then connected
directly at connections points along the single cable, for example at bases of road-light
poles along a motorway. Moreover, the single cable is beneficially double-insulated
or screened for personnel and equipment safety reasons; for example, such a single
cable is manufactured for operation at 230 V potential or less or more, and includes
Aluminium or copper conductors which may each have for example a 25 or 50 mm
2 cross-sectional area, and also includes an outer screen enclosed within an overall
outer insulating sheath. The cross section chosen is often calculated based upon a
maximum accepted voltage drop and not by the heat generated in use. The reasoning
for this is that the total length of the main cable may have a length of some kilometres
that might otherwise result in unacceptable voltage drops. Pursuant to conventional
practice, at each connection point along the cable, the cable conventionally has to
be dismantled and insulated conductors and screen wires brought to connection apparatus.
Such conventional practice has many disadvantages associated therewith, for example
corrosion, time consuming during installation, flashover and so forth.
Summary of the invention
[0007] The present invention seeks to provide improved cable branching which addresses one
or more aforementioned problems associated with known cable connection apparatus;
the problems concern one or more of: time consuming cable connection, difficulty operating
in wet and/or damp conditions, space restrictions for making connections.
[0008] According to a first aspect of the present invention, there is provided a power cable
clamp for making electrical connection to an adapted main cable including one or more
insulated and sheathed conductors, wherein the clamp is adapted for making connection
to the one or more conductors,
characterized in that
the clamp is provided with an electrical contact arrangement providing at least one
contact point onto an associated conductor of the cable and that the clamp is also
provided with at least one layer of sealing around the contact arrangement.
[0009] The invention is of advantage in that the power cable clamp is capable of providing
greater reliability in wet and/or damp conditions by using one or more contact points
and multiple stages of sealing from external environment to the cable.
[0010] Optionally, for the cable clamp, the clamp is adapted to register angularly onto
the conductor by way the clamp being provided with curved regions and cusp regions
on its surface adapted for registering onto the conductor, such that the curved regions
and cusp regions are adapted to conform to an outer surface presented the conductor
towards the clamp.
[0011] Optionally, for the cable clamp, the clamp is fabricated in one element which is
adapted to be attached via features for receiving cable ties, the clamp thereby being
retained upon the insulated and sheathed conductors of the cable.
[0012] Optionally, for the cable clamp, the outer casing is fabricated from at least two
portions which are adapted to be pivoted together for being retained on the cable
and enclosing the one or more clamps.
[0013] Optionally, for the cable clamp the electrical contact arrangement encompasses a
first flexible material of the flexible material region is adapted to be elastically
and or plastically deformed when the one or more contact points are brought into forced
contact with their associated conductor of the cable for sealing from ingress of moisture
in operation of the one or more contact points. More optionally for the cable clamp
arrangement, the electrical contact arrangement is provided with a second flexible
material gasket region peripherally therearound, and wherein the flexible material
is adapted to be elastically and or plastically deformed when the one or more contact
points are brought into forced contact with their associated conductor of the cable
for sealing from ingress of moisture in operation of the one or more contact points
and which is integrated in the curved region of the clamps around the connector block.
More optionally for the cable clamp arrangement, the electrical contact arrangement
is provided with a third flexible material region in which the one or more contact
points are embedded, the flexible material of the third flexible material region is
adapted to be elastically and or plastically deformed when the one or more contact
points are brought into forced contact with their associated conductor of the cable
for sealing from ingress of moisture in operation of the one or more contact points.
[0014] According to a second aspect of the invention, there is provided a preparation apparatus
for preparing a cable for the cable clamp arrangement pursuant to the first aspect
of the invention: there is provided a preparation apparatus for preparing a cable
including one or more insulated conductors for receiving a cable clamp arrangement
pursuant to the first aspect of the invention, wherein the preparation apparatus includes
a housing including an inner surface adapted to conform to an outer surface presented
by the one or more conductors for angularly registering the preparation apparatus
to the one or more conductors, and wherein the preparation apparatus is provided with
one or more guide holes for guiding a tool when milling, or otherwise producing, one
or more holes onto or into the one or more conductors, preferably with flat bottom
regions, to the one or more holes.
[0015] Optionally, for the preparation apparatus, the housing includes two pivotally coupled
parts providing with a locking arrangement for securing the housing around one or
more conductors for preparation thereof for subsequently receiving the cable clamp
arrangement.
[0016] According to a third aspect of the invention, there is provided a method of installing
at least one cable clamp pursuant to the first aspect of the invention: there is provided
a method of installing a cable clamp pursuant to the first aspect of the invention,
wherein the method includes:
- (a) coupling a preparation apparatus to the cable for angularly registering the preparation
apparatus to said insulated and sheathed conductors;
- (b) producing, by milling or otherwise, one or more holes via one or more guide holes
through the sheath and insulation material of said one or more conductors to expose
electrically conductive metal of said one or more conductors;
- (c) coupling at least one clamp of said cable clamp arrangement to said one or more
conductors for making electrical connections to electrically conductive metal of said
one or more conductors via said at least one clamp;
- (d) tightening at least one tie around said at least one clamp and said one or more
conductors so that, through the process of tightening, said flexible materials from
their flexible insulating materials regions ooze, thereby improving the sealing for
the one or more contact points from ingress of moisture in operation; and
- (e) installing an outer casing of said cable clamp arrangement around said one or
more clamps for protecting said one or more clamps.
[0017] Optionally, the method includes at least partially filling a region formed between
an inner surface of the outer casing of the at least one cable clamp and the cable
with at least one of: insulating filling material, anti-corrosion and/or anti-tracking
material.
[0018] It will be appreciated that features of the invention are susceptible to being combined
in any combination without departing from the scope of the invention as defined by
the accompanying claims.
Description of the diagrams
[0019] Embodiments of the present invention will now be described, by way of example only,
with reference to the following diagrams wherein:
- FIG. 1
- is a schematic illustration of an embodiment of a cable clamp arrangement pursuant
to the present invention;
- FIG. 2A
- is an illustration of a clamp element of a clamp of the apparatus of FIG. 1;
- FIG. 2B
- is an illustration of a manner in which the clamp of FIG. 2A accommodates a cable;
- FIG. 3
- is a side view of a manner in which a connection is made to an individually insulated
and sheathed conductor of a cable within the cable clamp arrangement of FIG. 1;
- FIG.4
- is an illustration of pre-cut holes in individually insulated and sheathed conductors
of a cable in preparation for receiving the cable clamp arrangement of FIG. 1;
- FIG. 5A
- is an illustration of a tool for use in preparing individually insulated and sheathed
conductors of cables in preparation for receiving the cable clamp arrangement of FIG.
1; and
- FIG. 5B
- is an illustration of cutting or milling bit for use with the tool of FIG. 5A to cut
and or mill.
[0020] In the accompanying diagrams, an underlined number is employed to represent an item
over which the underlined number is positioned or an item to which the underlined
number is adjacent. A non-underlined number relates to an item identified by a line
linking the non-underlined number to the item. When a number is non-underlined and
accompanied by an associated arrow, the non-underlined number is used to identify
a general item at which the arrow is pointing.
Description of embodiments of the invention
[0021] Referring to FIG. 1, there is shown a schematic illustration of a cable clamp arrangement
pursuant to the present invention. The apparatus is indicated generally by
10 and includes an outer casing
20 for locating onto, and optionally sealing around. The outer casing
20 is beneficially manufactured from a robust insulating plastics material, for example
from some polymer, polypropylene, polyethylene, polyurethane, nylon, rubber, and is
optionally armoured with one or more rigid members for ensuring that the casing
20 is resistant to being collapsed or otherwise mechanically damaged in use. Moreover,
the cable
40 includes one or more individually insulated and sheathed conductors
50. The one or more insulated and sheathed conductors
50 are optionally in a straight parallel arrangement, or are disposed in a helical formation
with an adapted lay-out length which is more compliant and tolerant to bending or
longitudinal stress experienced by the cable
40 when in use. The outer casing
20 defines an inner volume
60 between itself and the cable
40 as illustrated. This inner volume
60 is capable of accommodating one or more clamp components
70A,
70B which are secured over a region of the cable
40. This inner volume
60 may optionally be partly or completely filled with a compound in order to restrict
water from penetrating into said volume
60. The clamp components
70A,
70B are provided with corresponding cables
80A,
80B respectively which extend via one or more ports
90A,
90B included within a general form of the outer casing
20 to a external region remote from the inner volume
60. The clamp components
70A,
70B are an important feature of the apparatus
10 pursuant to the present invention on account of:
- (i) a manner in which they seals to insulation of their one or more conductors 50;
- (ii) a manner in which they makes an electrical connection to metal conducting portions
of their one or more conductors 50; and
- (iii) a manner in which they angularly registers to a bundle of conductors 50 for ensuring reliable mechanical retention thereto.
It will be appreciated that the apparatus 10 optionally includes multiple clamp components 70 for coupling to various individually sheathed and insulated cores 50 present within the apparatus 10.
[0022] The clamp components
70 will now be described in greater detail with reference to FIG. 2A and FIG. 2B. Each
clamp component
70 comprises a part-circular element
100. The part-circular element
100 does not necessary cover the whole of the circumference. The element
100 is formed to include curved regions
110 and cusp regions
120 designed to conform around the insulation and sheath of the conductors
50 to ensure that the element
100 is not prone to twisting around when clamped around the insulation and sheath of
the conductors
50 in use. The curved regions
110 and the cusp regions
120 are beneficially adapted to conform to a spiral disposition of the conductors as
illustrated in FIG. 1, FIG. 2A and FIG. 2B. Alternatively, the curved regions
110 and the cusp regions
120 are adapted to a configuration of straight parallel conductors
50. Optionally, the element
100 includes one or more features
300,
310 for receiving a "cable tie" or similar ratchet-binding component; such a cable tie
is beneficially fabricated from metal strips, plastics material or similar. The arrangement
with such an element
100 is not necessary covering the whole of the circumference. As illustrated in FIG.
2A and FIG. 2B, the element
100 includes an elongate projection
130 into which the cable
80 is terminated onto a conductor block; the elongate projection
130 is conveniently referred to as being a "connector housing". The projection
130 houses an electrical contact arrangement, usually spring loaded contacts (SLC), in
a conductor block
160, an optional soft insulation material
270 such as u-butyl rubber or similar material around the conductor block
160, and a plurality of pointed conductor pins (SLC)
180 embedded within the optional insulation material
270 and in electrical communication with the aforesaid conductor block
160. The soft insulation material beneficially includes a peripheral projecting ring
gasket feature adjacent to the conductor block
160 for providing an enhanced quality of hermetic sealing. Optionally, an additional
sealing "O"-ring gasket or some elastic and plastic material, e.g. some mastic material,
denoted by
280 in FIG. 3, is also provided around the conductor block
160, or in substitution thereto, for providing a further hermetic seal of the electrical
contact arrangement to the outer insulation of the conductor
50. The gasket
280 may alternatively be produced with an initial outer profile formed along the outer
surface of the conductor
50. On the mid part of the curved region
110 in FIGS. 2A, 2B and 3, the curved region
110 where the hole is produced, an additional mastic material
290 may be adapted and which is compressible during the assembly of the clamps
70. To summarize, this describes a threefold sealing of the contact area including the
sealing elements of
290,
280 and
270.
250 is also a sealing element around the conductor block
160 and this is produced from the u-butyl rubber or similar material when the ties or
strips get tightened and the material of sealing element
280 oozes and then comprises the sealing element
250. Before this tightening, the sealing element
250 as indicated in FIG. 2A does not necessary exist.
[0023] Next, a method of installing the apparatus
10 illustrated in FIG. 1 onto a length of cable
40 will be described. The method is implemented to implement finally the apparatus
10 illustrated in FIG. 1. A result of the method is to ensure that the electrical contact
arrangement couples the cable
80 to its corresponding insulated conductor
50 in a manner as depicted in FIG. 3. The conductor pins (SLC)
180 penetrate into metal of the insulated conductor
50 via a flat-bottomed hole which is pre-grinded into through the insulation
260 of the conductor
50 and a short distance into metal of the conductor
50, for example in an order of a 0,5 or 1 mm depth. Such penetration ensures that insulation
material
270 individually may seal to the metal of the conductor
50 for each of its pins 180, namely each pin 180 is individually hermetically sealed.
Moreover, the outer flexible material
250 provides an extra barrier of protection against ingress of moisture, thereby reducing
a risk of corrosion occurring when the apparatus
10 is employed in wet and/or damp conditions. The present invention effectively employs
in practice an electrical contact arrangement for making an electrical connection
to a conductor of a cable, wherein the arrangement simultaneously penetrates the conductor
at several spatial locations and synergistically also provides multiple stages of
hermetic sealing to avoid ingress of moisture. Such multiple barriers not only protect
against corrosion but also reduce a risk of flash-over occurring at elevated potentials,
for example in excess of 1 kV, or even for elevated potentials in an order of 36 kV.
[0024] The method includes a series of steps which will now be described in more detail.
[0025] The main cable preferably consists of five conductors
50, individually insulated and sheathed. The conductor itself is made of an electrically
conductive material, such as aluminium or copper. To increase flexibility and elongation
to break the conductors are annealed during or after the drawing process. The diameter
of the conductors is made even and exact to fit the later cutting or milling process.
To decrease the possibility of longitudinal ingress of water from an eventual hole/cut
through the later applied insulation and sheath the conductors are made of solid metal.
[0026] The insulation is made of an electrically insulating material for example cross-linked
Polyethylene/XLPE. It is placed in one or more layers around the conductor with a
specific thickness and in a way, by a specific extrusion technique, so that the insulation
forms a continuous layer in the whole length of the core and with close contact with
the conductor to decrease the possibility of longitudinal ingress of water from an
eventual hole/cut through the later applied sheath and the insulation.
[0027] The individual sheath placed on top of the insulation is made of an electrically
insulating material for example a specific PVC-compound or a so called halogen-free,
flame retardant compound in one or more layers around the insulated conductor with
a specific thickness and in a way, by a specific extrusion technique, so that the
sheath forms a continuous layer in the whole length of the core and with close contact
with the insulation to decrease the possibility of longitudinal ingress of water from
an eventual hole/cut through the applied sheath and the insulation. To avoid long
term deteriorating ageing effects between the insulation and sheath the sheath compound
is made with specific components to avoid negative compatibility effects as reduced
mechanical properties of the sheath and insulations materials and to avoid eventual
migration of possible migrating components included in the recipe of the sheath and
insulation compounds/materials and the connector base material.
[0028] The conductors are twisted together with a specific lay-up length to improve the
cable flexibility and to fit the later used preparation apparatus for cutting or milling
the holes in the sheath and insulation for connection of the electrical connectors
at the right spot.
[0029] The branch cable is made with solid conductors or stranded conductors, typically
made of Copper. The insulation material may be based on XLPE, PVC or so called halogen-free,
flame retardant materials. The cable may have a common bedding or inner sheath, polymer
compound placed above the insulated cores. The cable may have a common screen made
of electrically conductive material. The cable has a common, protective sheath typically
made based on PVC or a so called halogen-free, flame retardant compound. The cross-section
of the conductor are of a size fitting the connection points inside the connector
and to avoid long term deteriorating ageing effects between the insulation and the
connector body the insulation compound is made with specific components to avoid negative
compatibility effects, as reduced mechanical properties of the insulation and the
connector body of the connector.
[0030] A first step optionally involves removing the individual sheath and insulation by
cutting or milling a hole in them and in the same operation produce a flat surface
on the outside of the solid metallic conductor to which the cable clamp arrangement
10 is to be installed in order to expose corresponding individually insulated and sheathed
conductors
50.
[0031] A second step involves clamping a preparation apparatus indicated generally by
400 in FIG. 5A onto the portion of the cable
40, to ensure a fixed and defined positioning of the holes
350. The preparation apparatus
400 comprises two half portions
410A,
410B pivotally coupled together by hinges
420 and secured together in a closed state by a closing mechanism
430 including user-operated handles
440. Inside surfaces of the portions 410A,
410B are machined or moulded to conform to an outer profile of the individually insulated
and sheathed conductors
50 as illustrated in FIG. 5A. Such conformity ensures that the preparation apparatus
400 is automatically angularly registered to the individually insulated and sheathed
conductors
50 of the cable
40 when the two portions
410A,
410B are pivoted and then secured together using the mechanism
430. Holes
450 are included at various positions along one or more of the portions
410A,
410B for receiving a flat-bottomed milling bit
500 which can be rotated by use of a hand drill or similar applying torque onto a shank
530 of the milling bit
500 as illustrated in FIG. 5B. The milling bit
500 is beneficially provided with a collar
520 remote from its flat-bottom milling surface
540, wherein the collar 520 abuts against an outer surface of the portions
410A,
410B as appropriate for preventing the milling bit
500 being advanced further than necessary into the metallic part of the conductor
50. When holes
350 are correctly formed into the conductors
50 for receiving the aforementioned clamp components
70, the holes
350 are shallow and flat-bottomed
360 for receiving ends of the one or more pins
180. There exist other means than by milling for producing holes through the cable sheath
and insulation and to produce beneficial surfaces on conductors, e.g. by drilling.
[0032] A third step of the method involves removal of the preparation apparatus
400 from the combined cable
40.
[0033] A fourth step of the method involves attaching one or more clamp components
70 to the combined cable
40 by way of joining together the clamp components
70, for example as illustrated in FIG. 2A, and FIG. 2B, so that electrical connections
are made to the conductors
50 in a manner as depicted in FIG. 3. The element
100 of the clamp component
70 are placed in respect of their associated conductor
50 to which electrical connections are to be made, and then cable ties or similar are
used to firmly attach the element
100 together with the bundle of conductors
50 to form the combined clamp component
70. This step also results in the different gasket regions
290,
280,
270 of the combined clamp component
70 ooze and thus produces sealing including
250 which is produced from the material in region
280.
[0034] A fifth step of the method involves optionally spraying the clamp components
70 and conductors
50 in the portion of the combined cable
40 with surface passivating material to reduce any tendency to flashover, corrosion
or surface tracking. Thereafter, the method involves coupling together component parts
of the outer casing
20 of the cable clamp arrangement
10 for completing installation of the cable clamp arrangement
10 to the combined cable
40.
[0035] The cable clamp arrangement
10 is susceptible to being modified in various ways. For example, the outer casing
20 can be designed to be replaced or accept additional cables
80 in an event that the more connections subsequently are found to be necessary to the
cable
40 after initial installation of the cable clamp arrangement
10. Optionally, the method involves a further step of filling the inner volume
60 of the outer casing
20 with filling material, for example potting silicone rubber, after the clamp components
70 have been installed and the outer casing
20 has been located into position and/or is being located into position.
[0036] The cable clamp arrangement
10 is beneficially fabricated from moulded plastics materials, for example butyl rubber
for flexible sealing components, and filled plastics materials for more rigid component
parts of the apparatus
10. Electrically connective parts of the apparatus
10 are beneficially fabricated from metal, for example aluminium, brass and/or copper.
The metallic connectors may be electroplated with a thin layer of electrically conductive
and corrosion resistant material. As aforementioned, although the apparatus
10 is described in the foregoing with cables
40 including a spiral configuration of insulated conductors
50, the apparatus
10 can be adapted to enable electrical connections to cables
40 include their insulated conductors
50 in a parallel straight configuration. Although use of the cable clamp arrangement
10 is explicitly described in the foregoing in association with making electrical connections
at lower regions of highway lamp units, the apparatus
10 can be used in numerous other contexts; for example, the apparatus
10 can be employed in underground street conduits for making connections to domestic
premises, in tall building facilities such as tall skyscrapers, along railway tracks
for feeding onto trackside transformers for conveying motive power, in agricultural
facilities in the future wherein combine harvesters and similar equipment will be
electrically propelled in a post-carbon World (post fossil fuel World), in airport
facilities for conveying power to lights along runways, and so forth.
[0037] The preparation apparatus
400 and component parts of the cable clamp arrangement
10 are beneficially supplied as a kit for users to employ when implementing electrical
connections to cables
40. Optionally, the preparation apparatus
400 is provided with an insert for adapting to the insulated conductors
50 of the combined cable
40, there being one type of insert for spiral insulated conductors
50 and another type of insert for straight insulated conductors 50, thereby rendering
the kit ubiquitous for a plurality of different cable types and sizes. Optionally,
the outer casing
20 of the apparatus
10 is fabricated from one ore more portions which can be attached and/or pivoted together
to encompass the one or more clamp components
70 therein.
[0038] Branching of power cables with power cable clamps
70 has many uses outside the examples described above. Some examples of use can be branching
of conductors for current to:
- Fans
- Sensors
- Rail points
- Lighting systems
- LED-based
- Emergency
- Direct current (DC) -distribution
- Battery charging depots
[0039] The power cable clamps
70, preparation apparatus
400 and outer casing
20 must be adapted to required currents and voltages, specific lay-up lengths and other
constructional details of the cables used, as well as the environment where the cables
and branching is to be used. Cables may vary from cables with 2 conductors up to 5
conductors or even more. The cables may have various specific lay-up lengths or may
even be straight.
[0040] Modifications to embodiments of the invention described in the foregoing are possible
without departing from the scope of the invention as defined by the accompanying claims.
Expressions such as "including", "comprising", "incorporating", "consisting of", "have",
"is" used to describe and claim the present invention are intended to be construed
in a non-exclusive manner, namely allowing for items, components or elements not explicitly
described also to be present. Reference to the singular is also to be construed to
relate to the plural. Numerals included within parentheses in the accompanying claims
are intended to assist understanding of the claims and should not be construed in
any way to limit subject matter claimed by these claims.
1. A power cable clamp (70) for making electrical connection to an adapted main cable
(40) including one or more insulated and sheathed conductors (50), wherein said clamp
(70) is adapted for making connection to the one or more conductors (50),
characterized in that
said clamp (70) is provided with an electrical contact arrangement (160, 180), providing
at least one contact point (180) onto an associated conductor (50) of the cable (40)
and said clamp (70) is also provided with at least one layer of sealing (290, 280,
250, 270) around said contact arrangement (160, 180).
2. A cable clamp (70) as claimed in claim 1, wherein said clamp (70) is adapted to register
angularly onto said conductor (50) by way of said clamp (70) being provided with curved
regions (110) and cusp regions (120) on its surfaces adapted for registering onto
said conductor (50), such that the curved regions (110) and cusp regions (120) are
adapted to conform to an outer surface presented by said conductor (50) towards said
clamp (70).
3. A cable clamp (70) as claimed in claim 1 or 2, wherein said clamp (70) is fabricated
one element (100) which is adapted to be attached via features (300, 310) for receiving
cable ties, said clamp (70) thereby being retained upon said conductor (50) of the
cable (40).
4. A cable clamp (70) as claimed in claim 1, 2 or 3, wherein the outer casing (20) is
fabricated from two or more portions which are adapted to be pivoted together for
being retained on the cable (40) and enclosing the one or more clamps (70).
5. A cable clamp (70) as claimed in any one of the preceding claims, wherein the electrical
contact arrangement (160, 180) encompasses a first flexible material of the flexible
material region (290) which is adapted to be elastically and or plastically deformed
when the one or more contact points (180) are brought into forced contact with their
associated conductor (50) of the cable (40) for sealing from ingress of moisture in
operation of the one or more contact points (180).
6. A cable clamp (70) as claimed in claim 5, wherein the electrical contact arrangement
(160, 180) is provided with a second flexible material gasket region (280) peripherally
therearound, and wherein the flexible material of the second flexible material region
(280) is adapted to be elastically and or plastically deformed when the one or more
contact points (180) are brought into forced contact with their associated conductor
(50) of the cable (40) for sealing from ingress of moisture in operation of the one
or more contact points (180) and which is integrated in the curved region of the clamps
(70, 100) around the conductor block (160).
7. A cable clamp (70) as claimed in claim 5 or 6, wherein the electrical contact arrangement
(160, 180) is provided with a third flexible material region (270) in which the one
or more contact points (180) are embedded, wherein flexible material of the third
flexible material region (270) is adapted to be elastically and or plastically deformed
when the one or more contact points (180) are brought into forced contact with their
associated conductor (50) of the cable (40) for sealing from ingress of moisture in
operation of the one or more contact points (180).
8. A cable clamp (70) as claimed in claim 5, 6 or 7, wherein the said one or more contact
points (180) are adapted to make contact to a flat-bottomed hole preformed into their
associated conductor (50) of the cable (40).
9. A preparation apparatus (400) for preparing a combined cable (40) including one or
more insulated conductors (50) for receiving a cable clamp (70) as claimed in any
one of claims 1 to 7, wherein said preparation apparatus (400) includes a housing
(410A, 410B) including an inner surface adapted to conform to an outer surface presented
by said one or more conductors (50) for angularly registering said preparation apparatus
(400) to said one or more conductors (50), and wherein said preparation apparatus
(400) is provided with one or more guide holes (450) for guiding a grinding, or otherwise
hole-producing tool (500).
10. A preparation apparatus (400) as claimed in claim 9, wherein said housing (410A, 410B)
includes pivotally coupled parts (410A, 410B) providing with a locking arrangement
(430, 440) for securing said housing around one or more conductors (50) for preparation
thereof for subsequently receiving the cable clamp arrangement (10).
11. A method of installing at least one cable clamp (70) as claimed in any one of claims
1 to 8, wherein said method includes:
(a) coupling a preparation apparatus (400) to the cable (40) for angularly registering
the preparation apparatus (400) to said insulated and sheathed conductors (50);
(b) producing, by milling or otherwise, one or more holes (350) via one or more guide
holes (450) through the sheath and insulation material (255) of said one or more conductors
(50) to expose electrically conductive metal of said one or more conductors (50);
(c) coupling at least one clamp (70) of said cable clamp arrangement (10) to said
one or more conductors (50) for making electrical connections to electrically conductive
metal of said one or more conductors (50) via said at least one clamp (70);
(d) tightening at least one tie around said at least one clamp (70) and said one or
more conductors (50) so that, through the process of tightening, said flexible materials
from their flexible insulating materials regions (290, 280, 270) ooze, thereby improving
the sealing for the one or more contact points (180) from ingress of moisture in operation;
and
(e) installing an outer casing (20) of said cable clamp arrangement (10) around said
one or more clamps (70) and said cable (40) for protecting said one or more clamps
(70).
12. A method as claimed in claim 11, including at least partially filling a region (60)
formed between an inner surface of an outer casing (20) of said at least one cable
clamp and said cable (40) with at least one of: insulating filling material, anti-corrosion
and/or anti-tracking material.
Amended claims in accordance with Rule 137(2) EPC.
1. A power cable clamp (70) for making electrical connection to an adapted main cable
(40) including one or more insulated and sheathed conductors (50), wherein said clamp
(70) is adapted for making connection to the one or more conductors (50), said clamp
(70) being provided with an electrical contact arrangement (160, 180), providing at
least one contact point (180) onto an associated conductor (50) of the cable (40)
and said clamp (70) being also provided with at least one layer of sealing (290, 280,
250, 270) around said contact arrangement (160, 180), characterized in that said clamp (70) is adapted to register angularly onto said conductor (50) by way
of said clamp (70) being provided with curved regions (110) and cusp regions (120)
on its surfaces adapted for registering onto said conductor (50), such that the curved
regions (110) and cusp regions (120) are adapted to conform to an outer surface presented
by said conductor (50) towards said clamp (70).
2. A cable clamp (70) as claimed in claim 1, wherein said clamp (70) is fabricated one
element (100) which is adapted to be attached via features (300, 310) for receiving
cable ties, said clamp (70) thereby being retained upon said conductor (50) of the
cable (40).
3. A cable clamp (70) as claimed in claim 1 or 2, wherein the outer casing (20) is fabricated
from two or more portions which are adapted to be pivoted together for being retained
on the cable (40) and enclosing the one or more clamps (70).
4. A cable clamp (70) as claimed in any one of the preceding claims, wherein the electrical
contact arrangement (160, 180) encompasses a first flexible material of the flexible
material region (290) which is adapted to be elastically and or plastically deformed
when the one or more contact points (180) are brought into forced contact with their
associated conductor (50) of the cable (40) for sealing from ingress of moisture in
operation of the one or more contact points (180).
5. A cable clamp (70) as claimed in claim 4, wherein the electrical contact arrangement
(160, 180) is provided with a second flexible material gasket region (280) peripherally
therearound, and wherein the flexible material of the second flexible material region
(280) is adapted to be elastically and or plastically deformed when the one or more
contact points (180) are brought into forced contact with their associated conductor
(50) of the cable (40) for sealing from ingress of moisture in operation of the one
or more contact points (180) and which is integrated in the curved region of the clamps
(70, 100) around the conductor block (160).
6. A cable clamp (70) as claimed in claim 4 or 5, wherein the electrical contact arrangement
(160, 180) is provided with a third flexible material region (270) in which the one
or more contact points (180) are embedded, wherein flexible material of the third
flexible material region (270) is adapted to be elastically and or plastically deformed
when the one or more contact points (180) are brought into forced contact with their
associated conductor (50) of the cable (40) for sealing from ingress of moisture in
operation of the one or more contact points (180).
7. A cable clamp (70) as claimed in claim 4, 5 or 6, wherein the said one or more contact
points (180) are adapted to make contact to a flat-bottomed hole preformed into their
associated conductor (50) of the cable (40).
8. A preparation apparatus (400) for preparing a combined cable (40) including one or
more insulated conductors (50) for receiving a cable clamp (70) as claimed in any
one of claims 1 to 6, wherein said preparation apparatus (400) includes a housing
(410A, 410B) including an inner surface adapted to conform to an outer surface presented
by said one or more conductors (50) for angularly registering said preparation apparatus
(400) to said one or more conductors (50), and wherein said preparation apparatus
(400) is provided with one or more guide holes (450) for guiding a grinding, or otherwise
hole-producing tool (500).
9. A preparation apparatus (400) as claimed in claim 8, wherein said housing (410A,
410B) includes pivotally coupled parts (410A, 410B) providing with a locking arrangement
(430, 440) for securing said housing around one or more conductors (50) for preparation
thereof for subsequently receiving the cable clamp arrangement (10).
10. A method of installing at least one cable clamp (70) as claimed in any one of claims
1 to 7, wherein said method includes:
(a) coupling a preparation apparatus (400) to the cable (40) for angularly registering
the preparation apparatus (400) to said insulated and sheathed conductors (50);
(b) producing, by milling or otherwise, one or more holes (350) via one or more guide
holes (450) through the sheath and insulation material (255) of said one or more conductors
(50) to expose electrically conductive metal of said one or more conductors (50);
(c) coupling at least one clamp (70) of said cable clamp arrangement (10) to said
one or more conductors (50) for making electrical connections to electrically conductive
metal of said one or more conductors (50) via said at least one clamp (70);
(d) tightening at least one tie around said at least one clamp (70) and said one or
more conductors (50) so that, through the process of tightening, said flexible materials
from their flexible insulating materials regions (290, 280, 270) ooze, thereby improving
the sealing for the one or more contact points (180) from ingress of moisture in operation;
and
(e) installing an outer casing (20) of said cable clamp arrangement (10) around said
one or more clamps (70) and said cable (40) for protecting said one or more clamps
(70).
11. A method as claimed in claim 10, including at least partially filling a region (60)
formed between an inner surface of an outer casing (20) of said at least one cable
clamp and said cable (40) with at least one of: insulating filling material, anti-corrosion
and/or anti-tracking material.