EP1002350A1

EP1002350A1 - Surge arrester having disconnector housed by end cap

Info

Publication number: EP1002350A1
Application number: EP98923871A
Authority: EP
Inventors: Steven P. Hensley
Original assignee: Joslyn Manufacturing Co
Current assignee: Joslyn Manufacturing Co
Priority date: 1997-08-06
Filing date: 1998-06-01
Publication date: 2000-05-24
Anticipated expiration: 2018-06-01
Also published as: BR9811131A; EP1002350B1; DE69809926D1; JP2001512895A; TW466813B; ID23967A; CN1282287C; CN1265780A; CA2296421A1; WO1999008353A1

Abstract

An apparatus includes a surge arresting element, first and second end caps, an arrester housing, and a fault disconnector. The surge arresting element is arranged to conduct in the presence of the surge on a power line. The first and second end caps are arranged to be electrically connected to the surge arresting element, and the second end cap forms a disconnector housing. The arrester housing is arranged to house the surge arresting element and the first and second end caps so that the disconnector housing is accessible from an exterior of the arrester housing. The fault disconnector is arranged to electrically disconnect the surge arresting element from the power line in the event of a fault, and the fault disconnector is housed within the disconnector housing formed by the second end cap. A fastener is arranged to fasten the surge arresting element, the first and second end caps, the arrester housing, and the fault disconnector to a mounting bracket so as to wedge the arrester housing between the mounting bracket and the second end cap in order to form a seal.

Description

SURGE ARRESTER HAVING DISCONNECTOR HOUSED BY END CAP

Related Application

This application is a continuation-in-part of

U.S. Application Serial No. 08/907,327 filed on August 6,

1997.

Technical Field of the Invention

The present invention relates to a surge ar¬

rester for shunting electrical surges to ground. More

particularly, the surge arrester of the present invention

may have a disconnect which disconnects the surge ar¬

rester from ground in the event of a failure of the surge

arrester.

Background of the Invention

Overvoltage surges, which travel along an elec-

trie power distribution system and which are not properly

averted or diverted, often damage transformers and other

electrical equipment of the electric power distribution system, as well as the electrical equipment of residen¬

tial, commercial and industrial customers supplied by the

electric power distribution system. Consequently, surge

arresters are commonly used in an electric power distri-

bution system for shunting overvoltage surges to system

ground before the overvoltage surges can damage the elec¬

trical equipment connected in, or to, the electric power

distribution system.

Typical surge arresters used in electric power

distribution systems can fail in a runaway condition.

When such a failure occurs, the surge arrester may ex¬

plode apart, potentially damaging nearby equipment and

injuring anyone who happens to be near. Therefore, it

has been a common prior art practice to provide surge

arresters with fault disconnectors which open the cir¬

cuits containing failed surge arresters. Usually, a

fault disconnector is connected between its corresponding

surge arrester and ground so that, when the fault discon¬

nector activates upon failure of the surge arrester, the

fault disconnector separates the surge arrester from its

ground connection. The separated ground connection not only disconnects the failed surge arrester from the elec¬

tric power distribution system, but also provides a visi¬

ble indication to a utility linesmen that the surge ar¬

rester has failed.

A typical fault disconnector includes a car¬

tridge, which may contain a predetermined amount of gun

powder, and which is heated as the surge arrester begins

to fail. When the cartridge heats sufficiently, it ex¬

plodes separating the surge arrester from its ground

connection. The amount of gun powder that is used in the

cartridge is sufficient to cause such separation but not

sufficient to cause damage or injury.

The cartridge, and the other elements of the

fault disconnector, are contained within a disconnector

housing that is a separate component of the surge ar¬

rester, that has an internally threaded hole for threaded

attachment to a housing of the surge arrester, and that

has an external threaded ground connector for attachment

to a ground lead. An electrical resister, which is an-

other element of the fault disconnector and which is

housed by the disconnector housing, is electrically connected between a surge arrester terminal and the grou¬

nd connector of the disconnector. Accordingly, when the

surge arrester fails, the current through the electrical

resister increases abnormally and generates enough heat

to trigger the cartridge causing it to break the disconn¬

ector housing and to separate the ground terminal from

the surge arrester.

The use of a separate disconnector housing in¬

creases the part count of a surge arrester which, in

turn, increases the manufacturing cost of the surge

arrester. The present invention is directed to a surge

arrester which reduces part count .

Summary of the Invention

In accordance with one aspect of the present

invention, a surge arrester comprises a surge arresting

element, first and second end caps, and a fault dis¬

connector. The surge arresting element is arranged to

conduct in the presence of a surge. The first end cap is

arranged to electrically connect the surge arresting ele-

ment to a first electrical line. The second end cap is electrically connected to the surge arresting element and

forms a disconnector housing. The fault disconnector is

arranged to electrically connect the second end cap to a

second electrical line, the fault disconnector is ar-

ranged to disconnect the surge arresting element from the

second electrical line in the event of a fault, and the

fault disconnector is housed within the disconnector

housing formed by the second end cap.

In accordance with another aspect of the pres-

ent invention, an apparatus for arresting a surge on a

power line comprises a surge arresting element, first and

second end caps, an arrester housing, and a fault

disconnector. The surge arresting element is arranged to

conduct in the presence of the surge on the power line.

The first end cap is arranged to electrically connect the

surge arresting element to a first electrical line. The

second end cap is electrically connected to the surge

arresting element, and the second end cap forms a

disconnector housing. The arrester housing is arranged

to house the surge arresting element and the first and

second end caps. The fault disconnector is arranged to connect the second end cap to a second electrical line,

the fault disconnector is arranged to disconnect the

surge arresting element from the second electrical line

in the event of a fault, and the fault disconnector is

housed within the disconnector housing formed by the

second end cap.

In accordance with yet another aspect of the

present invention, a surge arrester comprises arrester

elements, an arrester housing, a mounting bracket, and a

fastener. The arrester elements are arranged to conduct

in the event of a surge. The arrester housing houses the

arrester elements. The mounting bracket supports the ar¬

rester elements and the arrester housing. The fastener

clamps the arrester elements and the arrester housing to

the mounting bracket so that the arrester housing is

wedged between the mounting bracket and the arrester

elements in order to form a seal for the arrester ele¬

ments .

In accordance with a further aspect of the

present invention, a surge arrester comprises a plurality

of surge arresting elements, an arrester housing, and a fault disconnector. A first of the surge arresting ele¬

ments is arranged to be electrically connected to a first

electrical line, a second of the surge arresting elements

is arranged to conduct in the presence of a surge, and a

third of the surge arresting elements forms a discon¬

nector housing. The arrester housing is arranged to

house the plurality of surge arresting elements so that

the disconnector housing is accessible from an exterior

of the arrester housing. The fault disconnector is ar-

ranged to electrically connect the third of the surge

arresting elements to a second electrical line, the fault

disconnector is arranged to disconnect the surge arrest¬

ing elements from the second electrical line in the event

of a fault, and the fault disconnector is housed within

the disconnector housing.

In accordance with a still further aspect of

the present invention, a surge arrester comprises ar¬

rester elements, an arrester housing, a mounting bracket,

and a threadless fastener. The arrester elements are

arranged to conduct in the event of a surge. The ar¬

rester housing houses the arrester elements. The mount- ing bracket supports the arrester elements and the ar¬

rester housing. The threadless fastener is arranged to

attach the arrester elements and the arrester housing to

the mounting bracket so that the arrester elements and

the arrester housing are supported by the mounting

bracket .

In accordance with a yet further aspect of the

present invention, a surge arrester comprises arrester

elements, an arrester housing, and an electrically

conductive connector. The arrester elements are arranged

to conduct in the event of a surge. The arrester housing

houses the arrester elements, and the arrester housing

has an integrally formed O-ring. The electrically

conductive connector cooperates with the integrally form-

ed O-ring to form a seal between an interior of the

arrester housing and an exterior of the arrester housing,

and the electrically conductive connector is arranged to

be electrically coupled to one of the arrester elements.

Brief Description of the Drawings These and other features and advantages of the

present invention will become more apparent from a de¬

tailed consideration of the invention when taken in con¬

junction with the drawings in which:

Figure 1 illustrates a first embodiment of a

surge arrester that includes a fault disconnector accord¬

ing to the present invention;

Figure 2 is an exploded view of the fault

disconnector illustrated in Figure 1;

Figure 3 is an enlarged view of a second

embodiment of a surge arrester according to the present

invention;

Figure 4 illustrates a third embodiment of a

surge arrester according to the present invention; and,

Figure 5 illustrates a fourth embodiment of a

surge arrester according to the present invention.

Detailed Description

As shown in Figure 1, a surge arrester 10 in¬

cludes a first terminal end 12 and a second terminal end

14. The first terminal end 12 includes a first connector 16 which is used to electrically connect the surge ar¬

rester 10 to a first electrical line. The second termi¬

nal end 14 includes a second connector 18 which is used

to electrically connect the surge arrester 10 to a second

electrical line. The first electrical line may be, for

example, an electrically conducting lead which connects

the first connector 16 to a high voltage line of an elec¬

trical power distribution system, and the second elec¬

trical line may be an electrically conducting lead which

connects the second connector 18 to ground. Alterna¬

tively, however, the first electrical line may be, for

example, an electrically conducting lead which connects

the first connector 16 to ground, and the second elec¬

trical line may be an electrically conducting lead which

connects the second connector 18 to a high voltage line

of an electrical power distribution system.

The first connector 16 is threaded into a first

end cap 20, and the second connector 18 is electrically

connected to a second end cap 22 in a manner to be de-

scribed below. The first and second end caps 20 and 22

are electrically conductive and, for example, may be formed from aluminum. A first surge arresting element 24

is in electrical contact with the first end cap 20, a

second surge arresting element 26 is in electrical con¬

tact with the first surge arresting element 24, a third

surge arresting element 28 is in electrical contact with

the second surge arresting element 26, and a fourth surge

arresting element 30 is in electrical contact with both

the third surge arresting element 28 and the second end

cap 22. Accordingly, a series circuit is formed between

the first and second end caps 20 and 22. The surge

arresting elements 24-30 may be metal oxide varistor

blocks, for example, which conduct in the presence of

surges in order to shunt the surge energy in the electric

power distribution system between the first and second

connectors 16 and 18.

An arrester housing 32 houses the first and

second end caps 20 and 22 and the surge arresting ele¬

ments 24, 26, 28, and 30. As is known, the arrester

housing 32 may be an insulating polymeric or porcelain

housing having a plurality of polymeric or porcelain

water sheds 34. A mounting bracket 36 is provided in order to mount and support the surge arrester 10 to a

utility pole or other apparatus of an electric power

distribution system.

As shown in Figures 1 and 2 , the second end cap

22 has a first end 40 which is in electrical contact with

the fourth surge arresting element 30. The second end

cap 22 also has a second end 42 which comprises a wall 44

forming a recess 46. A fault disconnector 47 includes a

cartridge 48 which is contained within an end 50 of the

second connector 18. The fault disconnector 47 also

includes a first electrically conductive washer 52 abut¬

ting the end 50 of the second connector 18, a second

electrically conductive washer 54 abutting an internal

wall 58 of the second end cap 22, and a resister 56

sandwiched between the first and second electrically

conductive washers 52 and 54. A plastic cup 59 contains

the first and second electrically conductive washers 52

and 54 and the resister 56 when the fault disconnector 47

is assembled as shown in Figure 1. Thus, the plastic cup

59 insulates the resister 56 and the first and second

electrically conductive washers 52 and 54 from the wall 44 of the second end cap 22 forcing fault current to flow

from the second end cap 22 through the second electri¬

cally conductive washer 54, through the resistor 56,

through the first electrically conductive washer 52, and

through the second connector 18.

The wall 44 of the second end cap 22 has a

circumferential groove 60 therearound. During assembly

of the surge arrester 10, the surge arresting elements

24, 26, 28, and 30 are stacked between the first and

second end caps 20 and 22. The stack formed by the surge

arresting elements 24, 26, 28, and 30 and the first and

second end caps 20 and 22 is wrapped with a fiber glass

weave in order to retain the surge arresting elements 24,

26, 28, and 30 and the first and second end caps 20 and

22 in the stack. The arrester housing 32 is applied to

the wrapped stack of the surge arresting elements 24, 26,

28, and 30 and the first and second end caps 20 and 22 as

shown in Figure 1. For example, the arrester housing 32

may be molded directly on the wrapped stack of the surge

arresting elements 24, 26, 28, and 30 and the first and

second end caps 20 and 22. The arrester housing 32 is mounted to the

mounting bracket 36 by inserting the wall 44 through an

opening 62 in the mounting bracket 36 as shown in Figure

1. The mounting bracket 36 may have a first recess 64

and a second recess 66 which are concentric with respect

to one another. The first recess 64 is formed by a gen¬

erally cylindrical wall 68 of the mounting bracket 36.

The generally cylindrical wall 68 may have an internal

taper. As the second end cap 22 is pushed through the

opening 62 in the mounting bracket 36, a flange 70 of the

second end cap 22 enters the second recess 66 of the

mounting bracket 36, and the taper of the generally cy¬

lindrical wall 68 causes an end portion 72 of the ar¬

rester housing 32 to be squeezed between the generally

cylindrical wall 68 and the flange 70 of the second end

cap 22. As a result of this squeezing action, the end

portion 72 acts as a gasket or seal at the second termi¬

nal end 14 in order to isolate the interior of the ar¬

rester housing 32 from the external environment. When

the arrester housing 32 is fully pressed into the opening

62 of the mounting bracket 36 so that the circumferential groove 60 is accessible, a snap ring 73 is snapped into

the circumferential groove 60 in the wall 44 of the sec¬

ond end cap 22 to thereby clamp the surge arrester 10 to

the mounting bracket 36 with enough force to maintain the

seal by the end portion 72 between the generally cylin¬

drical wall 68 and the flange 70 of the second end cap

22.

A subassembly 74 is formed by inserting the

second connector 18, with the cartridge 48 inserted in

the end 50, through the plastic cup 59 until the plastic

cup 59 abuts a flange 76 at the end 50 of the second

connector 18, and by inserting the first electrically

conductive washer 52 into the plastic cup 59 until the

first electrically conductive washer 52 abuts the flange

76 at the end 50 of the second connector 18. The re¬

sister 56 is inserted into the plastic cup 59 until the

resister 56 abuts the first electrically conductive wash¬

er 52, and the second electrically conductive washer 54

is placed on top of the resister 56. The subassembly 74

is then inserted into the recess 46 of the second end cap

22 until the second electrically conductive washer 54 abuts the internal wall 58, leaving a space 78 as shown

in Figure 1. The space 78 is filled with an epoxy pot¬

ting material in order to hold the subassembly 74 in

electrical contact with the second end cap 22.

Accordingly, the recess 46 in the second end

cap 22 forms a disconnector housing for the fault discon¬

nector 47 so as to eliminate the need for a separate

housing for the fault disconnector 47.

Instead of using the snap ring 73 in the

circumferential groove 60 of the second end cap 22 to

clamp the first and second end caps 20 and 22, the surge

arresting elements 24, 26, 28, and 30, and the arrester

housing 32 to the mounting bracket 36, the second end cap

22 may be threaded into the mounting bracket 36. To this

end, the second end cap 22 may be externally threaded at

a region 80 as shown in Figure 3.

As shown in Figure 1, the arrester housing 32

is formed over the first end cap 20 so as to provide a

seal in cooperation with a flange 90 of the first connec-

tor 16. This seal at the first terminal end 12 isolates

the interior of the arrester housing 32 from the external environment. Alternatively, the arrester housing 32 may

be configured with an integral O-ring 92 as shown in

Figure 4. The integral O-ring 92 fits within an annular

groove 94 about a first end cap 20A in order to provide a

seal at the first terminal end 12 that isolates the inte¬

rior of the arrester housing 32 from the external envi¬

ronment .

Instead of configuring an integral O-ring

according to the integral O-ring 92 shown in Figure 4, an

integral O-ring 100 may be provided as shown in Figure 5.

The integral O-ring 100 is integrally formed in the ar¬

rester housing 32 at its top and defines an opening 102

through which the first connector 16 extends so that it

may be threaded into the first end cap 20. The integral

O-ring 100 fits within an annular recess 104 formed in a

flange 106 of the first connector 16. As the first con¬

nector 16 is threaded into the first end cap 20, the

integral O-ring 100 is tightly squeezed into the annular

recess 104 and cooperates with the flange 106 in order to

provide a seal at the first terminal end 12 that isolates the interior of the arrester housing 32 from the external

environment .

Certain modifications of the present invention

have been discussed above. Other modifications will

occur to those practicing in the art of the present

invention. For example, the first connector 16 and the

first end cap 20 are shown as being separate elements.

Instead, the first connector 16 and the first end cap 20

may be formed as a single, integrated, electrically con-

ductive element .

Also, four surge arresting elements 24, 26, 28,

and 30 are shown in Figure 1 as being electrically con¬

nected between the first and second end caps 20 and 22.

However, any number of surge arresting elements may be

provided between the first and second end caps 20 and 22

depending upon the voltage carried by the electric power

distribution system and/or depending upon the particular

construction of the surge arresting elements.

Moreover, as described above, the surge ar-

rester 10 is assembled in the following order. First,

the surge arresting elements 24, 26, 28, and 30 are stacked between the first and second end caps 20 and 22,

the stack formed by the surge arresting elements 24, 26,

28, and 30 and the first and second end caps 20 and 22 is

wrapped with a fiber glass weave, and the arrester hous-

ing 32 is applied to the wrapped stack of the surge

arresting elements 24, 26, 28, and 30 and the first and

second end caps 20 and 22. Second, this arrangement is

then secured to the mounting bracket 36. Third, the

subassembly 74 is applied to the second end cap 22.

Instead, the surge arrester 10 may be assembled in any

desired order. For example, the surge arresting elements

24, 26, 28, and 30 may be first stacked between the first

and second end caps 20 and 22, the stack formed by the

surge arresting elements 24, 26, 28, and 30 and the first

and second end caps 20 and 22 may be wrapped with a fiber

glass weave, and the arrester housing 32 may be applied

to the stacked surge arresting elements 24, 26, 28, and

30 and first and second end caps 20 and 22. Second, the

subassembly 74 may be applied to the second end cap 22.

Third, the resulting arrangement may be then secured to

the mounting bracket 36. Additionally, the first and second end caps 20

and 22 may be referred to as surge arresting elements

insofar as they facilitate the surge arresting function

described above .

Furthermore, the plastic cup 59 may be formed

of any type of electrical insulating material other than

plastic .

Also, an electrically conductive spring, such

as a spring washer, may be inserted between the second

electrically conductive washer 54 and the internal wall

58.

Accordingly, the description of the present

invention is to be construed as illustrative only and is

for the purpose of teaching those skilled in the art the

best mode of carrying out the invention. The details may

be varied substantially without departing from the spirit

of the invention, and the exclusive use of all modifica¬

tions which are within the scope of the appended claims

is reserved.

Claims

WHAT IS CLAIMED IS:

1. A surge arrester comprising:

a surge arresting element, wherein the surge

arresting element is arranged to conduct in the presence

of a surge;

a first end cap arranged to electrically con-

nect the surge arresting element to a first electrical

line;

a second end cap electrically connected to the

surge arresting element, wherein the second end cap forms

a disconnector housing; and,

a fault disconnector arranged to electrically

connect the second end cap to a second electrical line,

wherein the fault disconnector is arranged to disconnect

the surge arresting element from the second electrical

line in the event of a fault, and wherein the fault

disconnector is housed within the disconnector housing

formed by the second end cap .

2. The surge arrester of claim 1 wherein the

first electrical line is a power line, and wherein the

second electrical line is substantially at ground.

3. The surge arrester of claim 1 wherein the

first and second end caps are in electrical contact with

the surge arresting element.

4. The surge arrester of claim 1 wherein the

surge arresting element is a metal oxide varistor.

5. The surge arrester of claim 1 wherein the

second end cap has first and second ends, wherein the

first end is in electrical engagement with the surge

arresting element, and wherein the second end of the

second end cap is recessed to form the disconnector hous┬¼

ing.

6. The surge arrester of claim 5 wherein the

first end of the second end cap is in direct electrical

engagement with the surge arresting element.

7. The surge arrester of claim 1 further

comprising a mounting bracket arranged to support the

surge arresting element, the first and second end caps,

and the fault disconnector.

8. The surge arrester of claim 7 further

comprising a fastener arranged to fasten the surge

arresting element, the first and second end caps, and the

fault disconnector to the mounting bracket so that the

mounting bracket is clamped between the second end cap

and the fastener.

9. The surge arrester of claim 8 wherein the

second end cap has first and second ends, wherein the

first end is in electrical engagement with the surge

arresting element, and wherein the second end of the

second end cap is recessed to form the disconnector hous┬¼

ing.

10. The surge arrester of claim 1 wherein the

surge arresting element comprises a plurality of surge

arresting elements .

11. An apparatus for arresting a surge on a

power line comprising:

a surge arresting element, wherein the surge

arresting element is arranged to conduct in the presence

of the surge on the power line;

a first end cap, wherein the first end cap is

arranged to electrically connect the surge arresting

element to a first electrical line;

a second end cap, wherein the second end cap is

electrically connected to the surge arresting element,

and wherein the second end cap forms a disconnector hous-

ing;

an arrester housing arranged to house the surge

arresting element and the first and second end caps;

and,

a fault disconnector, wherein the fault

disconnector is arranged to connect the second end cap to a second electrical line, wherein the fault disconnector

is arranged to disconnect the surge arresting element

from the second electrical line in the event of a fault,

and wherein the fault disconnector is housed within the

disconnector housing formed by the second end cap.

12. The apparatus of claim 11 wherein the

second electrical line is substantially at ground.

13. The apparatus of claim 11 wherein the

first and second end caps are in electrical contact with

the surge arresting element .

14. The apparatus of claim 11 wherein the

surge arresting element is a metal oxide varistor.

15. The apparatus of claim 11 wherein the

second end cap has first and second ends, wherein the

first end is in electrical engagement with the surge

arresting element, and wherein the second end of the second end cap is recessed to form the disconnector hous┬¼

ing.

16. The apparatus of claim 11 wherein the

arrester housing forms a substantially O-ring seal with

respect to the first end cap.

17. The apparatus of claim 11 wherein the

first end cap has first and second ends, wherein the

second end is in electrical engagement with the surge ar-

resting element, and wherein the arrester housing forms a

seal over the first end of the first end cap.

18. The apparatus of claim 11 further compris-

ing a mounting bracket arranged to support the surge

arresting element, the first and second end caps, the

arrester housing, and the fault disconnector.

19. The apparatus of claim 18 wherein the

arrester housing is arranged to form a seal with respect

to the mounting bracket and the second end cap.

20. The apparatus of claim 18 further compris-

ing a fastener arranged to fasten the surge arresting

element, the first and second end caps, the arrester

housing, and the fault disconnector to the mounting

bracket so that mounting bracket is clamped between the

second end cap and the fastener.

21. The apparatus of claim 20 wherein the

arrester housing is arranged to be wedged between the

mounting bracket and the second end cap when the mounting

bracket is clamped between the second end cap and the

fastener so as to form a seal .

22. The apparatus of claim 20 wherein the

mounting bracket has first and second recesses, wherein

the first recess is formed by a wall of the mounting

bracket, wherein the wall is tapered, wherein the second

recess is arranged to receive a flange of the second end

cap, and wherein the arrester housing is arranged to be

wedged between the tapered wall of the mounting bracket

and the flange of the second end cap when the mounting bracket is clamped between the second end cap and the

fastener so as to form a seal .

23. The apparatus of claim 18 wherein the

second end cap has first and second ends, wherein the

first end is in electrical engagement with the surge

arresting element, and wherein the second end of the

second end cap is recessed to form the disconnector hous┬¼

ing.

24. The apparatus of claim 11 wherein the

surge arresting element comprises a plurality of surge

arresting elements.

25. A surge arrester comprising:

arrester elements, the arrester elements being

arranged to conduct in the event of a surge;

an arrester housing that houses the arrester

elements;

a mounting bracket that supports the arrester

elements and the arrester housing; and, a fastener that clamps the arrester elements

and the arrester housing to the mounting bracket so that

the arrester housing is wedged between the mounting

bracket and the arrester elements in order to form a seal

for the arrester elements.

26. The surge arrester of claim 25 wherein the

arrester elements comprise an end cap, wherein the end

cap has first and second ends, wherein the first end is

in electrical engagement with another of the arrester

elements, and wherein the second end of the second end

cap is recessed to form a disconnector housing.

27. The surge arrester of claim 26 further

comprising a fault disconnector, wherein the fault

disconnector is arranged to be in electrical series with

the arrester elements, wherein the fault disconnector is

arranged to disconnect the arrester elements from an

electrical line in the event of a fault, and wherein the

fault disconnector is housed within the disconnector

housing formed by the end cap.

28. The surge arrester of claim 25 wherein the

mounting bracket has first and second recesses, wherein

the first recess is formed by a wall of the mounting

bracket, wherein the second recess is arranged to receive

a flange of one of the arrester elements, and wherein the

arrester housing is arranged to be wedged between the

wall of the mounting bracket and the flange of the one

arrester element when the arrester elements and the ar┬¼

rester housing are clamped to the mounting bracket.

29. The surge arrester of claim 28 wherein the

wall is tapered, and wherein the arrester housing is ar-

ranged to be wedged between the tapered wall of the

mounting bracket and the flange of the one arrester ele-

ment when the arrester elements and the arrester housing

are clamped to the mounting bracket .

30. The surge arrester of claim 28 wherein the

arrester elements comprise an end cap, wherein the end

cap has first and second ends and the flange, wherein the

first end is in electrical engagement with another of the arrester elements, and wherein the second end of the

second end cap is recessed to form a disconnector hous┬¼

ing.

31. The surge arrester of claim 30 further

comprising a fault disconnector, wherein the fault

disconnector is arranged to be in electrical series with

the arrester elements, wherein the fault disconnector is

arranged to disconnect the arrester elements from an

electrical line in the event of a fault, and wherein the

fault disconnector is housed within the disconnector

housing formed by the end cap.

32. The surge arrester of claim 25 wherein the

arrester elements comprise an arrester block and first

and second end caps .

33. The surge arrester of claim 32 wherein the

arrester block comprises more than one arrester block.

34. The surge arrester of claim 25 wherein the

mounting bracket has a recess, wherein the recess is

formed by a wall of the mounting bracket, and wherein the

arrester housing is arranged to be wedged between the

wall of the mounting bracket and one of the arrester

elements .

35. The surge arrester of claim 34 wherein the

one of the arrester elements is an end cap.

36. The surge arrester of claim 35 wherein the

end cap houses a fault disconnector.

37. A surge arrester comprising:

a plurality of surge arresting elements, where-

in a first of the surge arresting elements is arranged to

be electrically connected to a first electrical line,

wherein a second of the surge arresting elements is ar-

ranged to conduct in the presence of a surge, and wherein

a third of the surge arresting elements forms a

disconnector housing;

an arrester housing arranged to house the

plurality of surge arresting elements so that the

disconnector housing is accessible from an exterior of

the arrester housing; and,

a fault disconnector arranged to electrically

connect the third of the surge arresting elements to a

second electrical line, wherein the fault disconnector is

arranged to disconnect the surge arresting elements from

the second electrical line in the event of a fault, and

wherein the fault disconnector is housed within the

disconnector housing.

38. The surge arrester of claim 37 wherein the

arrester housing is a polymeric housing.

39. The surge arrester of claim 37 wherein the

arrester housing is a porcelain housing.

40. A surge arrester comprising:

arrester elements, the arrester elements being

arranged to conduct in the event of a surge;

an arrester housing that houses the arrester

elements;

a mounting bracket that supports the arrester

elements and the arrester housing; and,

a threadless fastener, wherein the threadless

fastener is arranged to attach the arrester elements and

the arrester housing to the mounting bracket so that the

arrester elements and the arrester housing are supported

by the mounting bracket .

41. The surge arrester of claim 40 wherein the

threadless fastener is a snap ring.

42. The surge arrester of claim 40 wherein the

arrester elements includes an end cap, and wherein the

threadless fastener engages the end cap in order to at-

tach the arrester elements and the arrester housing to

the mounting bracket.

43. The surge arrester of claim 42 wherein the

end cap has a first end electrically coupled to another

of the arrester elements and a second end protruding

through the mounting bracket, and wherein the threadless

fastener engages the second end of the end cap.

44. The surge arrester of claim 43 wherein the

second end of the end cap has a groove, and wherein the

threadless fastener engages the groove in the second end

of the end cap.

45. The surge arrester of claim 44 wherein the

threadless fastener is a snap ring.

46. The surge arrester of claim 40 wherein the

arrester elements comprise an arrester block and first

and second end caps .

47. The surge arrester of claim 46 wherein the

arrester block comprises more than one arrester block.

48. The surge arrester of claim 46 wherein the

arrester block has first and second ends, wherein the

first end cap is electrically coupled to the first end of

the arrester block, wherein the second end cap is elec-

trically coupled to the second end of the arrester block,

and wherein the threadless fastener engages the second

end cap in order to attach the arrester elements and the

arrester housing to the mounting bracket.

49. The surge arrester of claim 48 wherein the

second end cap has a first end electrically coupled to

the arrester block and a second end protruding through

the mounting bracket, and wherein the threadless fastener

engages the second end of the second end cap.

50. The surge arrester of claim 49 wherein the

second end of the second end cap has a groove, and where-

in the threadless fastener engages the groove in the

second end of the second end cap.

51. The surge arrester of claim 50 wherein the

threadless fastener is a snap ring.

52. The surge arrester of claim 48 wherein the

arrester block comprises first and second arrester block-

s, wherein each of the first and second arrester blocks

has first and second ends, wherein the first end cap is

electrically coupled to the first end of the first ar-

rester block, and wherein the second end cap is electri-

cally coupled to the second end of the second arrester

block.

53. The surge arrester of claim 40 wherein the

mounting bracket has a recess, wherein the recess is

formed by a wall of the mounting bracket, and wherein the

arrester housing is arranged to be wedged between the wall of the mounting bracket and one of the arrester

elements when the threadless fastener attaches the ar-

rester elements and the arrester housing to the mounting

bracket .

54. The surge arrester of claim 53 wherein the

one of the arrester elements is an end cap, wherein the

end cap has a first end electrically coupled to another

of the arrester elements and a second end protruding

through the mounting bracket, and wherein the threadless

fastener engages the second end of the end cap in order

to attach the arrester elements and the arrester housing

to the mounting bracket.

55. The surge arrester of claim 54 wherein the

second end of the end cap has a groove, wherein the

threadless fastener is a snap ring, and wherein the snap

ring engages the groove in the second end of the end cap.

56. The surge arrester of claim 40 wherein the

mounting bracket has first and second recesses, wherein the first recess is formed by a wall of the mounting

bracket, wherein the second recess is arranged to receive

a flange of one of the arrester elements, and wherein the

arrester housing is arranged to be wedged between the

wall of the mounting bracket and the flange of the one

arrester element when the arrester elements and the ar┬¼

rester housing are attached to the mounting bracket .

57. A surge arrester comprising:

arrester elements, the arrester elements being

arranged to conduct in the event of a surge;

an arrester housing that houses the arrester

elements, the arrester housing having an integrally form-

ed O-ring; and,

an electrically conductive connector cooperat-

ing with the integrally formed O-ring to form a seal

between an interior of the arrester housing and an

exterior of the arrester housing, wherein the electri-

cally conductive connector is arranged to be electrically

coupled to one of the arrester elements .

58. The surge arrester of claim 57 wherein the

electrically conductive connector has a flange forming a

recess, and wherein the recess receives the O-ring.

59. The surge arrester of claim 57 wherein the

arrester housing has an opening through which the

electrically conductive connector extends, wherein the

opening has first and second ends and is circumscribed by

a wall extending between the first and second ends and

defining the opening, wherein the integrally formed O-

ring is integrally formed around the wall, and wherein

the electrically conductive connector has an annular

groove that receives the O-ring to form the seal.

60. The surge arrester of claim 57 further

comprising a mounting bracket that supports the arrester

elements and the arrester housing.

61. The surge arrester of claim 60 further

comprising a fastener that clamps the arrester elements

and the arrester housing to the mounting bracket so that

the arrester housing is wedged between the mounting

bracket and one of the arrester elements in order to form

a seal for the arrester elements.

62. The surge arrester of claim 61 wherein the

electrically conductive connector has a flange forming a

recess, and wherein the recess receives the O-ring.

63. The surge arrester of claim 60 wherein the

mounting bracket has a recess, wherein the recess is

formed by a wall of the mounting bracket, and wherein the

arrester housing is arranged to be wedged between the

wall of the mounting bracket and one of the arrester

elements.

64. The surge arrester of claim 63 wherein the

electrically conductive connector has a flange forming a

recess, and wherein the recess receives the O-ring.

65. The surge arrester of claim 60 wherein the

mounting bracket has first and second recesses, wherein

the first recess is formed by a wall of the mounting

bracket, wherein the second recess is arranged to receive

a flange of one of the arrester elements, and wherein the

arrester housing is arranged to be wedged between the

wall of the mounting bracket and the flange of the one

arrester element when the arrester elements and the ar┬¼

rester housing are clamped to the mounting bracket.

66. The surge arrester of claim 65 wherein the

wall is tapered, and wherein the arrester housing is ar-

ranged to be wedged between the tapered wall of the

mounting bracket and the flange of the one arrester ele-

ment when the arrester elements and the arrester housing

are clamped to the mounting bracket .