Attach_07_VAFB_Electrical_Material_Specifications_Part3.pdf

JUNE 2006 OHIO BRASS – AIKEN, SC

31-�

POWER SYSTEMS, INC.

©Copyright 2006 Hubbell/Ohio Brass • 1850 Richland Avenue East • Aiken, SC 29801 NOTE: Because Hubbell has a policy of continuous product improvement, we reserve the right to change design and specifications without notice.

Warranty - Material Hubbell Power Systems, Inc. warrants all products sold by it to be merchantable (as such term is defined in the Uniform Commercial Code) and to be free from defects in material and workmanship. Buyer must notify the Company promptly of any claim under this warranty. The Buyer’s exclusive remedy for breach of this warranty shall be the repair or replacement, F.O.B.

factory, at the Company’s option, of any product defective under the warranty which is returned to the Company within one year from the date of shipment. NO OTHER WARRANTY, WHETHER

EXPRESS OR ARISING BY OPERATION OF LAW, COURSE OF DEALING, USAGE OF

TRADE OR OTHERWISE IMPLIED, SHALL EXIST IN CONNECTION WITH THE COMPANY’S

PRODUCTS OR ANY SALE OR USE THEREOF. The Company shall in no event be liable for any loss of profits or any consequential or special damages incurred by Buyer. The Company’s warranty shall run only to the first Buyer of a product from the Company, from the Company’s distributor, or from an original equipment manufacturer reselling the Company’s product, and is non-assignable and non-transferable and shall be of no force and effect if asserted by any per-son other than such first Buyer. This warranty applies only to the use of the product as intended by Seller and does not cover any misapplication or misuse of said product.

Warranty - Application

Hubbell Power Systems, Inc. does not warrant the accuracy of and results from product or system performance recommendations resulting from any engineering analysis or study. This applies regardless of whether a charge is made for the recommendation, or if it is provided free of charge.

Responsibility for selection of the proper product or application rests solely with the purchaser. In the event of errors or inaccuracies determined to be caused by Hubbell Power Systems, Inc. , its liability will be limited to the re-performance of any such analysis or study.

Table of Contents Page

Warranty ..........................................................................................31-2 Introduction ......................................................................................31-3 PDV/PVR Distribution Surge Arresters ............................................31-3

Alloy ESP Housing .......................................................................31-3 Basic Construction .......................................................................31-3 Benefits ........................................................................................31-3

Tests Verify PDV/PVR Arrester Design............................................31-4 Full Scale Fault Current Tests ......................................................31-4 Design Test Report Summary ......................................................31-4 Optima Design Improvements .....................................................31-4

DynaVar PDV/PVR Selection Considerations .............................................................31-5 Temporary Overvoltage ...................................................... 31-5, 31-6

Mounting Hardware Optional Attachments ...................................................................31-7 How to Specify a 7000 Code Suffix .............................................31-7 Tightening Torques for PDV/PVR Arrester Fasteners ..................31-7 Options Table ...............................................................................31-7

PDV/PVR Electrical Characteristics ................................................31-8 Insulation Coordination ....................................................................31-9

PDV/PVR

Dimensions ................................................................................31-10 Leakage Distances ....................................................................31-10 Dimension Diagrams..................................................................31-10

Typical Mounting Configurations and Hardware ............................................................................31-11

PDV Optima Testaments ...............................................................31-12

FA461019RA029 - ATTACHMENT 07

JUNE 2006

31-3

OHIO BRASS – AIKEN, SC

POWER SYSTEMS, INC.

Basic Construction

In the PDV/PVR arresters, the Varistors are locked in place with tightly wound layers of fiberglass filament impregnated with epoxy resin. The arrester housing is made from our proprietary blend of ESP silicone alloy. In addition to ESP’s exceptional performance as an insulator material, ESP’s properties have been confirmed in a series of performance tests which include tracking resistance, contamination, aging, and seal design.

The PDV/PVR arresters can be used with all standard mounting arms and brackets. They come with all the necessary fasteners, isolators, and terminal attachments. A specially designed glass-filled polyester insulating bracket, with integrated disconnector, along with optional mounting brackets such as the cross arm or transformer bracket, enable mounting the arrester in a way which best suits each individual customer.

Below is a typical cross section view of one of our distribution type arresters.

Cutaway View of Typical PDV/PVR Unit

Introduction

The PDV-100 arrester was introduced in 1986 as the very first U.S. non-ceramic arrester for heavy duty applications. Now, 18 years and 15 million arresters later, we are pleased to introduce the newest addition to the Ohio Brass arrester family, the PDV-100 Optima.

Ohio Brass offers a full line of polymer arresters for distribution voltages. The newest in the line, the PDV-100 Optima, adds all the benefits of a heavy duty distribution arrester, combined with a new disconnector which improves system reliability and increases TOV capability. The PVR targets cable applications where low discharge voltages promote longer cable life.

The PDV-65 is our normal duty arrester offering cost effective protection.

The PDV-100 Optima joins an impressive list of advances that Ohio Brass has brought to arrester technology since it began making arresters in 1950.

Improvements in design, such as the Optima have increased protective margins and durability. More important in terms of dollars and service reliability, Ohio Brass arresters have generated substantial savings for utilities. On the following pages are additional benefits and capabilities of our arresters.

Benefits of the NEW PDV-100 Optima

• Improved Isolator Reliability

• Patented Isolator Design Good Down to One Amp

Operation

• Saves Utilities Money and Improves System Reliability

• New Universal Protective Cap

• Higher 60 Hz TOV Capability

• Field Proven Sealing System

Stainless Steel Terminal Stud

Stainless Steel Cap

End Terminal

Live Silicone Interface

Alloy ESP Rubber Housing

Metal Oxide Varistor

Belleville Washer

Epoxy-Fiberglass Wrap

Metal Oxide Varistor

POWER SYSTEMS, INC.

Tests Verify PDV/PVR Arrester Design Full Scale Fault Current Tests Short circuit design tests were performed on PDV65, PDV100 Optima, and PVR arresters in accordance with Section 8.18 of IEEE C62.11-2004 Standard. Eight arresters of each type were tested. Per the standard, four samples were tested at the claimed high current withstand capability. Two of these samples were assembled with internal fuse wires. The other two were good arresters which were subjected to an overvolt-age condition, which failed the arrester (with a weak source).

The arrester was immediately subjected to the claimed high current fault current. Two additional arresters were subjected to fault currents approximately half of the claimed high current value. The fault current duration for all high current tests was 12 cycles. Finally, two arresters were subjected to a nominal 600 amp, 1 second fault current test. All test arresters were 17 kV MCOV, the longest single module configuration used for each arrester type. Tests were performed at full voltage (17 kV rms).

Successful performance was demonstrated when the ep-oxy-fiberglass wrapped arrester modules burned through to relieve internal pressures associated with the fault current arcing. In all cases, the arrester remained intact, except at the high current levels which caused polymer housing fragmenta-tion, which is acceptable.

The following table summarizes the claimed short circuit capabilities for the arresters.

Arrester Type

PDV 65

PDV 65

PDV 65

PDV 100 Optima PDV 100 Optima PDV 100 Optima

PVR

PVR

PVR

Short Circuit Test Duration-Sec.

.20

.20 1.0 .20 .20 1.0 .20 .20 1.0

PDV/PVR Design Test Report Summary The PDV-100 Optima and PDV-65 arresters have been tested in accordance with IEEE Standard C62.11-2004 for metal-ox-ide surge arresters. There is no standard for PVR arresters so they were tested per the heavy duty requirement.

The PDV-100 Optima/PVR meet or exceed all the require-ments for heavy-duty distribution arrester designs. The PDV- 65 meets or exceeds all requirements for normal duty surge arresters.

The table below summarizes the capabilities of these designs.

Heavy Duty PDV-100 Optima +Riser Pole PVR

2 - 100 kA Discharges

20 - 250A x 2000 µsec Discharges

20 - 10 kA plus 2 - 40 kA Discharges

Test

High Current- Short Duration Low Current

Long Duration Duty Cycle

Normal Duty

PDV-65

2 - 65 kA Discharges

20 - 75A x 2000 µsec Discharges

22 - 5 kA Discharges

Short Circuit Test Current Arms

15,000 7,500

20,000 10,000

20,000 10,000

The above is merely a summary of a portion of the design tests performed on PDV/PVR arresters. Contact your Ohio Brass sales representative for complete test reports on these two arresters.

PDV-100 Optima Design Improvements

The new Ohio Brass PDV-100 Optima incorporates a redesigned disconnector and a new line end protective cap.

Both of these are aimed at improving the overall system reliability.

Improved Disconnector Reliability

Historically distribution class surge arresters were installed with a ground lead disconnecting device. The purpose of this component is to allow a failed (shorted) arrester to automatically disconnect from the line. This allowed the line to quickly be returned to service and also provided a visual indication to crews as to which arrester had failed and needed to be replaced.

Occasionally under conditions that allowed a low fault current to flow through the arrester - damage will occur to the disconnector’s internal grading resistor. When this condition occurs the disconnector will not operate. With the introduction of polymer arrester designs this situation was aggravated since it was nearly impossible to identify a failed arrester from the ground and the circuit would be locked out.

The PDV-100 Optima design incorporates a patented capacitor-graded Optima disconnector into the insulated bracket attached to the base end of the arrester.

The following curve shows that the low current end of the detonation range for the capacitor-graded Optima disconnector has been extended from 20 amps down to 1 amp. This assures proper disconnector operation even at very low fault current levels.

Laboratory testing has confirmed that the electrical integrity of the capacitor-graded Optima disconnector is not affected by exposure to prolonged TOV conditions or 100 kA lightning duty. In the unlikely event of arrester failure, it does ensure proper detonation of the disconnector, separating the arrester ground lead and preventing lockout from occurring.

New Universal PDV 100 Optima Protective Cap

The new Optima line end protective cap is designed for single or thru connection lead wires. Each side of the cap has webbed fingers which prevent accidental contact with the arrester top end hardware by wildlife.-

OHIO BRASS – AIKEN, SC

POWER SYSTEMS, INC.

Effectively Grounded

Neutral Circuits

2.55

7.65 7.65 8.4 8.4 12.7 15.3

15.3 22.0

Maximum 2.54 4.4 5.08 7.26 12.7 13.2

13.97 14.52 22.0 24.2 24.34 26.4 36.5

Nominal 2.4

4.16 4.8 6.9 12.0 12.47 13.2 13.8 20.78 22.86 23.0 24.94 34.5

Impedance Grounded and Ungrounded Circuits

2.55 5.1 5.1 7.65 12.7

15.3 22.0 22.0 22.0

Arrester MCOV-kVSystem L-L Voltage kV

NORMALLY RECOMMENDED DYNAVAR PDV/PVR

MCOV FOR VARIOUS SYSTEM VOLTAGES

Selection of arrester size is based upon the maximum continuous operating voltage (MCOV) that is applied across the arrester in service (line-to-ground). For ar-resters on effectively grounded systems, this is normal-ly the maximum line-to-ground voltage -- e.g., 7.65 kV on a 12.47 kV multi-grounded system. For ungrounded or impedance-grounded systems, the MCOV should be at least 90 percent of maximum phase-to-phase voltage. Smaller arresters than shown may be used, contact your Ohio Brass representative for details.

For convenience, the data shown in this catalog in-cludes the traditional duty-cycle voltage rating associ-ated with the MCOV of each arrester.

The selection of the actual type will be primarily gov-erned by the insulation being protected.

Selection Considerations

MOV arresters by nature are voltage sensitive devices.

At normal line to ground voltages, the arrester is en-ergized at its MCOV (Maximum Continuous Operating Voltage) and conducts very little current. During distur-bances on the system, the arrester can see elevated voltages and therefore higher 60Hz current through the unit. The magnitude and duration of the system-gener-ated temporary over voltage (TOV) that the arrester can withstand is best expressed graphically. The two curves on the next page shows the TOV capability ver-sus time for OB distribution style arresters. The PDV-

Temporary Overvoltage

100 Optima demonstrates an improved TOV capability.

The capacitance-based isolator as in a PDV-Optima improves the TOV capability while increasing the reli-ability of disconnector function. The PDV-100 Optima technology results in a family of TOV curves that are a function of voltage rating of the arrester. Curves for other ratings can be found in our design test report on-line at http://www.hubbellpowersystems.com. Contact your HPS representative for more information on this new technology.

POWER SYSTEMS, INC.

OHIO BRASS – AIKEN, SC

POWER SYSTEMS, INC.

*Must be ordered in conjunction with codes 7000, 7060 or 7070.

Procedure (Example) To obtain the 7000 code suffix number for a 10 kV duty cycle rated PDV-65 arrester equipped with a line ter-minal, wire clamp, insulating base bracket, NEMA crossarm hanger for a 4 x 5 crossarm and a ground lead isolator with terminal nut, follow this procedure:

Step 1 - The catalog number (page 8) of the basic 10 kV PDV-65 arrester is 217259.

Step 2 - The 72XX code in the table below specifies the top terminal and wire clamp.

Step 3 - The 7X2X code specifies the insulating base bracket and 4 x 5 NEMA crossarm hanger.

Step 4 - The 7XX4 code specifies the ground lead isolator, terminal nut and nut.

Step 5 - Combine the three suffix digits following the 7 in their correct order gives us the suffix code: 7224.

Step 6 - Order the arrester by complete catalog number 2172597224.

For all PDV-100 Optima Arresters:

The 73XX code will be the only one with a cap. The 74XX code is not available since the Optima only has one cap style which is the newest design.

7XX3

Isolator, Nut, Ground Strap Washer

7XX2*

Nut, Washers & Threaded Terminal Nut

7XX1*

3/8” Stud (No Option)

7XX6*

Ground Strap, Nut, Washers & Threaded Terminal Nut

7XX5

Isolator, Nut, Protective Cap (2 Slot), Washer & Threaded Terminal Nut

7XX4

Isolator, Nut, Washer & Threaded Terminal Nut

7XX7*

Nut, Washers & Threaded Terminal Nut

TABLE C LOWER TERMINAL HARDWARE

7X0X No Bracket No Isolator

7X1X Insulated Base Bracket with Isolator

7X3X Insulated Base Bracket with Isolator and Transformer Bracket

7X2X Insulated Base Bracket with Isolator & NEMA 4x5 X-Arm Bracket

7X5X Insulated Base Bracket with Isolator & NEMA 6x6 X-Arm Bracket

7X6X Metal Base Mounting Strap

7X4X Insulated Base Bracket with Isolator and NEMA Angle Bracket

7X7X Metal Base Mounting Strap and NEMA 4x5 X-Arm Bracket

TABLE B MOUNTING HARDWARE

71XX

3/8” Stud (No Option)

72XX

Nut & Wire Clamp

73XX

Nut, Wire Clamp & Protective Cap (One Slot)

74XX

Nut, Wire Clamp & Protective Cap (One Hole)

75XX

Nut, Wire Clamp, Protective Cap (One Slot), & 18” Wire Lead

TABLE A TOP TERMINAL HARDWARE

Recommended Tightening Torque 20 foot pounds 20 foot pounds 20 foot pounds

Fastener 3⁄8 inch line terminal 3⁄8 inch ground terminal 1⁄2 inch fastener connecting base bracket to crossarm or transformer sidewall bracket

76XX

Flipper Fuse Assembly Nut & Wire Clamp

77XX

Nut, Wire Clamp, 3-Piece Protective Cap

RECOMMENDED TIGHTENING TORQUES FOR

PDV ARRESTER FASTENERS

How to Specify a 7XXX Suffix Hardware Code

Notes:

1. The ground isolator identified in codes 7003, 7004 and 7005 is an integral part of the insulating base bracket. The color for the insulating base bracket/ground lead isolator as-sembly is ANSI-70 gray.

2. Code 7030 identifies the insulating base bracket/trans-former mounting bracket combination. The transformer mounting bracket used in code 7030 is Ohio Brass part num-ber 2730664004 (≤ 8.4 kV MCOV) and 2730254004 (≥ 10.2 kV MCOV). A drawing of the 273066 bracket is in-cluded on page 11 to assist in applying this arrester. Contact your HPS representative for further information.

3. All terminals are solderless, clamp type, suitable for con-ductor sizes from No. 6 AWG solid to No. 2 AWG stranded.

If the spacing of the mounting holes on mounting brackets listed are not suitable for the intended application, other mounting brackets are available and in these cases, the HPS sales representative should be consulted.

FA461019RA029 - ATTACHMENT 07

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POWER SYSTEMS, INC.

8/20 Maximum Discharge Voltage - kV

8/20 Maximum Discharge Voltage - kV

1.5 kA

9.8 19.5 26.0 27.0 33.8 43.1 50.1 54.5 67.7 76.9 83.9 104.0

3 kA

10.3 20.5 28.0 29.5 36.3 46.3 53.8 58.5 72.7 82.6 90.2 112.0

5 kA

11.0 22.0 30.0 31.5 38.5 49.0 57.0 62.0 77.0 87.5 95.5 120.0

10 kA

12.3 24.5 33.0 36.0 42.8 54.4 63.3 68.9 85.5 97.2 106.1 132.0

20 kA

14.3 28.5 39.0 41.5 49.0 62.4 72.6 79.0 98.1 111.5 121.7 156.0

40 kA

18.5 37.0 50.5 53.0 59.7 76.0 88.4 96.1 119.4 135.6 148.0 202.0

Unit Cata-log

Number

217253 217255 217258 217259 217560 213263 213265 213267 217570 213272 213274 217579

0.5 µsec 5kA Maximum

IR-kV(1)

12.5 25.0 33.5 36.0 42.4 54.0 62.8 68.3 84.9 96.4 105.2 134.0

500 A Switching Surge Maximum IR-kV(2)

8.5 17.0 23.0 24.0 31.3 39.9 46.4 50.5 62.7 71.2 77.7 92.0

Rated Voltage kV

MCOV

kV

2.55 5.1

7.65 8.4 10.2 12.7 15.3 17.0 19.5 22.0 24.4 29.0

Normal Duty DynaVar PDV-65

Riser-Pole DynaVar PVR

1.5 kA

8.0 15.9 23.3 25.4 30.3 38.5 45.4 51.1 61.3 68.8 75.7 97.9

3 kA

8.5 17.0 24.9 27.1 32.3 41.1 48.4 54.5 65.5 73.4 80.7 97.0

5 kA

9.0 18.0 26.4 28.8 34.2 43.5 51.3 57.8 69.3 77.8 85.5 102.7

10 kA

9.9 19.8 29.0 31.6 37.6 47.8 56.4 63.5 76.2 85.5 94.0 112.9

20 kA

11.1 22.3 32.6 35.6 42.3 53.8 63.5 71.4 85.7 96.2 105.8 127.0

40 kA

13.2 26.5 38.8 42.3 50.3 64.0 75.5 85.0 102.0 114.4 125.8 151.1

Rated Voltage kV

Unit Catalog Number

213703 213705 213708 213709 213710 213713 213715 213717 213720 213722 213724 213729

0.5 µsec 10kA Maximum

IR-kV (1)

10.6 21.3 31.2 34.0 40.4 51.4 60.6 68.3 81.9 91.9 101.1 121.4

500 A Switching Surge Maximum IR-kV(2)

7.6 15.3 22.4 24.4 29.0 36.9 43.5 49.0 58.8 65.9 72.5 87.0

MCOV

kV

2.55 5.1

7.65 8.4 10.2 12.7 15.3 17.0 19.5 22.0 24.4 29.0

Heavy Duty PDV-100 Optima

Electrical Characteristics

Rated 0.5 µsec 500 A Voltage MCOV Catalog 10kA Maximum Switching Surge kV kV Number IR-kV(1) Maximum IR-kV(2) 1.5 kA 3 kA 5 kA 10 kA 20 kA 40 kA

03 02.55 221603 9.9 6.6 7.2 7.8 8.2 9.1 10.4 12.3 06 5.1 221605 20.0 13.3 14.6 15.7 16.6 18.3 21.0 24.8 09 7.65 221608 26.8 17.8 19.5 21.0 22.2 24.5 28.1 33.2 10 8.4 221609 29.5 19.6 21.5 23.1 24.4 27.0 31.0 36.6 12 10.2 221610 35.5 23.6 25.9 27.9 29.4 32.5 37.3 44.0 15 12.7 221613 44.2 29.4 32.2 34.7 36.7 40.5 46.5 54.8 18 15.3 221615 53.4 35.5 38.9 41.9 44.3 48.9 56.1 66.2 21 17.0 221617 60.7 40.3 44.3 47.6 50.3 55.6 63.8 75.3 24 19.5 221620 70.9 47.1 51.7 55.6 58.7 64.9 74.4 87.9 27 22.0 221622 78.6 52.2 57.3 61.7 65.2 72.0 82.6 97.5 30 24.4 221624 88.5 58.7 64.5 69.4 73.3 81.0 92.9 110.0 36 29.0 221629 105.0 69.7 76.5 82.4 87.0 96.1 110.0 130.0

8/20 Maximum Discharge Voltage - kV

All Ohio Brass Arresters are fully compliant with ANSI/IEEE C62.11 Standard

(1) Maximum discharge voltage for a 10-kA impulse current wave which produces a voltage wave cresting in 0.5 µs. This can be used for coordination where front-of-wave sparkover was formerly used.

(2) Based on a 500A surge of 45-µs time to crest.

FA461019RA029 - ATTACHMENT 07

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OHIO BRASS – AIKEN, SC

POWER SYSTEMS, INC.

Fig. 1

PDV-100

METAL-OXIDE ARRESTER INSULATION COORDINATION

34.5 kV System

Fig. 2

PDV-65

METAL-OXIDE ARRESTER INSULATION COORDINATION

34.5 kV System

Insulation Coordination These electrical characteristics are used to determine protective margins for insulation levels in use.

These two figures illustrate a 34.5 kV effectively ground-ed system, 150 kV BIL, protected with 22 kV MCOV Type PDV arresters.

Figure 1 shows equipment protected with a PDV-100 arrester Catalog Number 213722 and Figure 2 shows the same equipment protected with a PDV-65 arrester Catalog Number 213272.

The protective margins are calculated using the following formula:

Insulation Level Arrester Discharge Voltage( - 1 x 100 = % Margin)

The insulation levels are obtained from the manufacturer of the equipment being protected. The arrester discharge voltages are obtained from the table on page 8.

For example, the protective margin for the BIL is deter-mined by first finding the arrester discharge voltage at the impulse current level selected. In this example, the 10 kA discharge current is used as representative of typical lightning stroke currents discharged through the arrester. The 10 kA 8/20 discharge voltage of catalog number 213722 is 85.5 kV. The percent protective mar-gin using the formula is:

( 150 kV

85.5 kV - 1 x 100 =75 percent.)

The protective margins for other impulse currents are found in a similar fashion. In the case of the PDV-65 ar-rester, the 10 kA 8/20 discharge voltage of the arrester is

97.2 kV. This results in a protective margin of 54 percent.

These examples include many simplifying assumptions.

Not included are the effects of faster rates of current rise on the discharge voltage, reduced insulation levels due to various factors, and line and ground leads.

For example, if the effect of lead length was included in the calculations and 1.6 kV per foot of lead length added to the discharge voltage of the arrester. With two feet of line lead and two feet of ground lead, 6.4 kV is added to the published discharge voltage of the arrester. There-fore, the discharge voltage of the PDV-100 is effectively

91.9 kV, resulting in a reduction of protective margin to 63 percent at 10 kA. In the case of the PDV-65 arrester, the 97.2 kV discharge voltage of the arrester is added to the 6.4 kV from the leads resulting in equipment seeing

103.6 kV reducing the protective margin to 44.7 percent.

The chopped wave strength of the insulation being pro-tected is typically coordinated with the .5 µsec discharge voltage of the surge arrester. The heavy duty PDV-100 uses a 10 kA current while the PDV-65 catalog value is for a 5 kA peak current.

The switching surge insulation level of the equipment is coordinated with the 500 ampere switching discharge voltage of the surge arrester.

The effects of faster rates of rise and of reduced insulation strength due to aging effects would result in further reduced pro-tective margins.

Industry standards recommend minimum margins of 20 percent for the chopped wave and BIL levels and 15 percent for switching surge protection.

Time to Voltage Crest in Microseconds

Time to Voltage Crest in Microseconds

C re st V o lt ag e in k

V

.1 1 10 100 1000 1000060Hz

C re st V o lt ag e in k

V

.1 1 10 100 1000 1000060Hz

31-10

POWER SYSTEMS, INC.

Mounting Clearance (1) Approx. Net Weights

Unit with Insulating Base

Bracket and NEMA Bracket pounds 5.4 5.8 6.3 6.3 6.8 8.1 8.1 8.7

10.8 11.3 11.7 12.8

Unit with Insu-lating

Base Bracket pounds

2.9 3.3 3.8 3.8 4.3 5.6 5.6 6.2 8.3 8.7 9.2

10.3

Unit Only pounds 1.9 2.3 2.8 2.8 3.3 4.6 4.6 5.2 7.0 7.4 7.9 9.0

Center Line to Ground inches

3.4 4.2 5.5 6.5 7.5 8.0 10.0 11.0 12.0 14.5

Center Line to

Center Line inches

5.4 6.2 7.5 8.5 9.5 10.0 12.0 13.0 14.0 16.5

Leakage Distance Terminal to Base inches

8.5 11.3 14.4 14.4 17.0 25.2 25.2 28.1 36.5 39.6 42.2 50.4

“X” Overall Height inches

6.8 7.6 8.7 8.7 9.3 11.6 11.6 12.4 15.3 16.4 16.9 19.3

MCOV

kV

2.55 5.1 7.65 8.4 10.2 12.7 15.3 17.0 19.5 22.0 24.4 29.0

Rated Voltage kV

Mounting Clearance (1) Approx. Net Weights

Unit with Insulating Base

Bracket and NEMA Bracket pounds 6.0 6.0 6.0 6.0

10.3 10.3 10.3 10.3 12.5 12.5 12.5 15.8

Unit with Insu-lating

Base Bracket pounds

3.5 3.5 3.5 3.5 6.7 6.7 6.7 6.7

10.0 10.0 10.0 13.3

Unit Only pounds 2.6 2.6 2.6 2.6 5.6 5.6 5.6 5.6 8.9 8.9 8.9

12.2

Center Line to Ground inches

3.2 3.8 4.1 5.7 6.7 7.7 8.2 10.2 11.2 11.8 14.4

Center Line to

Center Line inches

4.8 5.6 5.8 7.5 8.5 9.5 13.6 16.2

Leakage Distance Terminal to Base inches

15.4 15.4 15.4 15.4 15.4 25.0 25.0 25.0 30.8 40.4 40.4 46.2

“X” Overall Height inches

9.4 9.4 9.4 9.4 9.4 12.4 12.4 12.4 14.7 17.8 17.8 20.8

MCOV

kV

2.55 5.1

7.65 8.4 10.2 12.7 15.3 17.0 19.5 22.0 24.4 29.0

Rated Voltage kV

Riser Pole DynaVar PVR

(1) Center line to center line is equivalent to phase-to-phase; center line to ground is equivalent to phase-to-ground. These are recommended minimum clearances only and as such are not intended to take precedence over existing construction codes or specifications.

For appropriate packed weight, add 0.5 lb. per arrester.

Mounting Clearance (1) Approx. Net Weights

Unit with Insulating Bracket, Isolator and NEMA Bracket pounds 5.8 6.6 6.6 6.6

6.8 8.0 8.6 8.6 9.9 12.1 12.1 13.3

Unit with Insu-lating

Base Bracket pounds

3.3 4.1 4.1 4.1 4.3 5.5 6.1 6.1

7.4 9.6 9.6 10.8

Unit Only pounds 2.3 3.1 3.1 3.1 3.3 4.5 5.1 5.1

6.1 8.3 8.3 9.5

Center Line to Ground inches

3.0 3.3 3.8 4.0 5.3 6.3 7.2 7.7 9.6 10.5 11.5 14.0

Center Line to

Center Line inches

5.0 5.3 5.8 6.0 7.3 8.3 9.2 9.7 11.6 12.5 13.5 16.0

Leakage Distance Terminal to Base inches

8.0 15.4 15.4 15.4 15.4 26.0 26.0 26.0 30.8 52.0 52.0 52.0

MCOV

kV

2.55 5.1 7.65 8.4 10.2 12.7 15.3 17.0 19.5 22.0 24.4 29.0

Rated Voltage kV

“X” Overall Height inches

7.0 9.4 9.4 9.4 9.4 12.4 12.4 12.4 14.7 21.1 21.1 21.1

Normal Duty DynaVar PDV-65

Heavy Duty DynaVar PDV-100 Optima

FA461019RA029 - ATTACHMENT

user Highlight This MCOV rating is to be used on North Vandenberg ONLY! Part Number 213710-7324 user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight user Highlight This MCOV rating is to be used on South Vandenberg ONLY! Part Number 213715-7324 user Note Marked set by user

31-11

OHIO BRASS – AIKEN, SC

POWER SYSTEMS, INC.

Typical Mounting Configurations and Hardware

PDV-100 Optima Catalog No. 2137157314

PDV-65

Catalog No. 2172657224

Transformer Mounting Part No. 2730664004

Standard Mounting Brackets

PVR

Catalog No. 2216157233

Crossarm Mounting Part No. 2734563001

FA461019RA029 - ATTACHMENT 07

user Cross-Out Use stainless steel mounting bracket in the ADSCO stainless section

31-1�

POWER SYSTEMS, INC.

Duty Cycle (kv) MCOV (kV) Original PDV-100 PDV-100 Optima 3 2.55 217602 213703 6 5.1 217605 213705 9 7.65 217608 213708 10 8.4 217609 213709 12 10.2 213510 213710 15 12.7 213613 213713 18 15.3 213615 213715 21 17 213617 213717 24 19.5 213520 213720 27 22 213622 213722 30 24.4 213624 213724 36 29 213629 213729

Fuse Specifications

Information compiled by: TSgt Russell Wells

TSgt Rus se ll W ell s

GENERAL

Kearney™ fuse links can be applied to a variety of applications requiring overcurrent protection of distribution systems and equipment. When proper-ly coordinated with other overcurrent protective devices, sectionalizing to isolate faulted feeder branches or equipment can be accomplished.

Kearney fuse links are available in a variety of types offering a wide selection of operating characteristics.

The links incorporate low melting temperature elements, captive wash-ers, high-resistance strain wires, color-coded high strength tubes, and Hi-Cor® corrosion resistant cables.

The low temperature melting tin elements enhance overload capability by guaranteeing non-damageability of the fuse tubes. These elements are capable of absorbing vibration as well as thermal shock due to current surges and heating and cooling throughout the daily load cycle. They can be further distinguished by their years of superb service proven by lab TCC verification of aged fuse links.

Consult your Cooper sales represen-tative for more details.

The fuse links meet the latest version of ANSI C37.42 and NEMA SG2.1 standards for fuse links.

The following are the types of fuse links offered:

■ Type K

■ Type T

■ Type 200 (N)

■ Type KS

■ Type QA

■ Type X

■ Secondary Indicating Fuses

■ Under-oil Fuses

INTERNAL

CONSTRUCTION

All Kearney fuse links are designed with low melting temperature element components of either tin or solder filled dual element construction. Each element material shipment from our supplier is accompanied with a certifi-cation of quality and composition. The diameter is verified in incoming inspection. Low melting temperature fuse links Types K, T, 200, X and KS have exceptional overload capability.

They are designed to carry 150% of their continuous current rating contin-uously without damage to the fuse link itself or to the cutout fuseholder in which they are installed. (Care should be exercised so that the current rating of the cutout is not exceeded.)

SINGLE TIN ELEMENT

Links using pure tin elements have a precision gauged strain wire crimped in parallel to provide tension loading properties. The tin element is soldered into position providing the industry’s best possible electrical connection between the element and its terminals.

The low melting temperature of the tin

Fusing Equipment

Kearney™ Fuse Links

Electrical Apparatus

K-SEC 030

1September 1999 • Supersedes 4/99 Printed in U.S.A.

Figure 1.

Fuse link packaging ensures proper selection and application.

Figure 2.

Internal construction features.

1. Tin element (in parallel with high strength strain wire to ensure mechanical strength of fuse).

2. Solder coil and tin element.

3. Body terminals made of pure copper.

4. Screw terminal.

5. High burst strength tube with fish paper liner.

4 1 3 5

4 1 3 5

4 2 3 5

4 2 3 5

This product was compiled by:

TSgt Russell C. Wells Vandenberg AFB, California se ll W ell s allows all of the fuse link components to operate at a lower temperature while providing long term reliable time-current characteristics (TCC).

DUAL ELEMENT

There are two dual element designs.

The dual element design for 1 and 2 A K, X, T, 200 (N), and QA link assem-blies is composed of a heater coil mounted around a solder pot that is soldered to a fuse element. Type KS and X links above 2 A have two wire elements in series which are axially inserted into a soldered coil.

Dual element links which use solder coils are mechanically crimped to the body and screw terminals. The elements are inserted into the coil and meticulously gauged to assure that active element lengths are main-tained. The soldering process then permanently sets the active elements to the proper TCC curve and guarantees positive electrical continuity.

Dual elements allow the fuse to respond as low temperature single element fuses for long time overloads, yet have superior lightning surge with-stand capability. Both types of links have up to 26 times more surge with-stand capability than single element fuse links.

FINAL CONSTRUCTION

After passing in-process QA checks, high strength color coded tubes are swaged to both the single and dual element fuse links. A unique self lock-ing washer and button is attached to the screw terminal. Every fuse link is axial pull tested to verify mechanical strength before packaging in the Kearney unique “lineman friendly” pull-tab fuse packs.

FUSE LINK SELECTION

Type K Kearney Type K fuse links meet the ANSI/NEMA requirements for a “fast” fuse. The nominal speed ratio of Type K fuse links is 7. Type K fuse links are well suited where “fast” time-current characteristics are desired such as for capacitor protection.

Type 200 (N) Kearney Type 200 fuse links are classified as “medium” speed fuses, with a nominal speed ratio of 10.

Type 200 fuse links provide more surge withstand capability than Type K links, and provide good coordination possibilities with relays and reclosers.

Type QA Kearney Type QA fuse links are classified as “medium” speed fuse links with a nominal speed ratio of 10.

Type QA fuse links will carry 100% of the rated current continuously without damage, and provide good coordina-tion possibilities with relays and reclosers.

Type T Kearney Type T fuse links meet the ANSI/NEMA requirements for a “slow” fuse link. The nominal speed ratio of Type T fuse links is 12. Type T fuse links provide slower time-current characteristics than Types K, 200, and QA, and coordinate well with relays and reclosers.

Kearney™ Fuse Links

Figure 3.

Fuse link features.

REMOVABLE BUTTONS

Allow fuse links to be used in all open and enclosed cutouts, including cutouts with arc-shortening rods.

CAPTIVE WASHER

Will not fall off prior to or during installation.

(Can be removed for use where 1/2” but-ton or no button is required.)

SWAGED FERRULE

Extends around fuse link tube to ensure single end expulsion on low fault currents.

HI-COR® CABLE

Has corrosion-resistant coating that extends the life of small cable. Used on all fuse links through 30 A.

AMPERE SIZE

Marked on top of screw terminal, so that it can be seen after the fuse link is installed in a fuseholder.

IDENTIFICATION

Fuse link type, ampere size and date of manufacture marked on periphery of screw terminal.

FUSE LINK TYPE

Marked on length of tube to aid in identification of fuse type.

COLOR CODE

High bust strength tube color coded for each fuse link to minimize the potential of installing wrong fuse link type.

SPRING

On all fuse links through 25 A to aid in clearance of low level faults by ejecting the fuse cable and creating a positive element separation.

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

Type KS Kearney Type KS fuse links employ dual element construction which gives the Type KS high surge withstand capability, and a nominal speed ratio of 20. Classified as “very slow” fuse links, the Type KS has greater surge current withstand capability than the Type T, and is a good choice for line fusing and transformer protection.

Type X Kearney Type X fuse links are specially designed for transformer protection.

Type X fuse links employ dual element construction, which allows the time-current characteristic to be carefully shaped to closely match the ANSI loading curve for transformers while providing excellent surge withstand to avoid nuisance blowing from lightning and switching surges. The nominal speed ratio of the Type X is 32.

PACKAGING

All fuse links are packed in individual cartons for the maximum protection and ease of use. Cartons are perforated for easy opening. Fuse links can be removed with gloves on. Fuse Link Type and Ampere Ratings are clearly marked on the carton. The print will not smear or run.

Five Pack Sleeves: Fuse Link Type and Ampere Rating are clearly marked on box front and end of cartons.

Individual cartons are tabbed so that remaining fuses stay securely in the carton as others are removed.

Overcartons: All fuse links 100 A and below are packed in protective over-cartons 25 per box. Catalog Number, Fuse Link Type, Ampere Rating, and Date of Manufacture are marked on the label for ease of selection.

COMPARATIVE MELTING

SPEED RATIO CHART

Electrical equipment such as transform-ers, switches, relays, and conductors are exposed to various levels of current during normal operation. Generally, electrical devices can withstand high currents for a short period of time and low current for longer periods of time without thermal or mechanical damage.

The ability to withstand various levels of current for various periods of time is referred to as time-current characteristics.

Coordination of power systems involves the selection of fuse links to protect equipment with various time-current characteristics while coordinating with reclosers, circuit breakers, sectionalizers, relays, and other fuses. Kearney offers six types of fuse links with a wide range of time-current characteristics (refer to Table 1).

The speed ratio of all fuse link sizes 100 A and below is the ratio between the current that melts the fuse in

0.1 seconds to the current that melts the fuse in 300 seconds. The higher the ratio, the slower the speed of melting.

For fuses rated above 100 A, the speed ratio is between the melting currents at 0.1 second and 600 seconds.

K-SEC 030

Single Element Dual Element

Designation Fast Medium Slow Very Slow Extra Slow

Type K 200, QA T KS X

Speed Ratio 6-8 7-11 10-13 20 32

Figure 4.

This chart compares the six speed ratios available with standard fuse link types which are fully adaptable to various coordination needs.

TABLE 1

Speed Ratio

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

Kearney™ Fuse Links

Figure 5.

Fit-All® cable fuse links.

* “L” dimension extends to the end of the fuse leader.

TABLE 2

Fit-All® Cable Fuse Links

Catalog Numbers

Current Rating Type X Type KS Type 200 Type QA Type K Type T

1/3 41033

1/2 41050

3/4 41075

1 41100 21001 11001 6413-2T 31001 51001

1 1/4 41125

1 1/2 41150

2 41200 21002 11002 6414-2T 31002 51002

2 1/2 41250

2 3/4 41275

3 21003 11003 6415-2T 31003 51003

3 1/2 41350

4 41400

5 21005 11005 6416-2T

5 1/2 41550

6 31006 51006

7 41007 21007 11007 6417-2T

8 31008 51008

10 41010 21010 11010 6418-2T 31010 51010

12 31012 51012

15 41015 21015 11015 6419-2T 31015 51015

20 21020 11020 6420-2T 31020 51020

25 21025 11025 6421-2T 31025 51025

30 21030 11030 6422-2T 31030 51030

40 21040 11040 6423-2T 31040 51040

50 21050 11050 6424-2T 31050 51050

60 6425-2T

65 21065 11065 31065 51065

75 6426-2T

80 21080 11080 31080 51080

100 21100 11100 6427-2T 31100 51100

125 21125 11125 6428-2T

140 31140 51140

150 21150 11150 6429-2T

175 11175 6724-2T

200 21200 11200 6725-2T 31200 51200

CATALOG INFORMATION B

A

D

C

L*

F

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

Current Rating (A) Fuse Link Types A* B* C* D* F* L*

1/2 to 2 X, KS, T, K, 200, QA 1/2” 3/4” 5 3/8” .269” 1 1/8” 23”

2 1/2 to 15 X 1/2' 3/4" 5 3/8” .305” 1 1/8” 23”

3 to 20 K 1/2' 3/4" 5 3/8” .305” 1 1/8" 23”

3 to 25 200, QA, KS, T 1/2' 3/4" 5 3/8” .305” 1 1/8" 23”

25 to 50 K 1/2' 3/4" 5 3/8” .305” N/A 23”

30 to 50 T, KS, 200 1/2" 3/4" 5 3/8” .305” N/A 23”

30 to 60 QA 1/2" 3/4" 5 3/8” .305” N/A 23”

65 to 100 K, T, KS, 200 3/4” 5 3/8” .396” N/A 23”

75 to 150 QA 3/4” 5 3/8” .396” N/A 23”

125 to 200 KS, 200 1” 6 3/8” .500” N/A 23”

140 to 200 K,T 1” 6 3/8” .500” N/A 23”

175 to 200 QA 1” 6 3/8” .500” N/A 23”

Catalog Numbers

Current Rating Type X Type KS Type 200 Type QA Type K Type T

1/3 42033

1/2 42050

3/4 42075

1 42100 22001 12001 6813 32001 52001

1 1/4 42125

1 1/2 42150

2 42200 22002 12002 6814 32002 52002

2 1/2 42250

2 3/4 42275

3 22003 12003 6815 32003 52003

3 1/2 42350

4 42400

5 22005 12005 6816

5 1/2 42550

7 42007 22007 12007 6817 32006 52006

8 32008 52008

10 42010 22010 12010 6818 32010 52010

12 32012 52012

15 42015 22015 12015 6819 32015 52015

20 22020 12020 6820 32020 52020

25 22025 12025 6821 32025 52025

30 22030 12030 7482 32030 52030

40 22040 12040 7483 32040 52040

50 22050 12050 7484 32050 52050

TABLE 3

Fit-All Fuse Link Dimensions

TABLE 4

Trip-O-Link Fuse Link Ordering Information

Figure 6.

Trip-o-Link fuse links.

K-SEC 030

*See Figure 5 8 1/2"

WARNING: Electrical shock from live electrical lines or energized equipment can cause serious bodily injury or death if persons or con-ductive materials they are using contact them. The time-current response of these fuse links will not protect against human injury from electrical shock.

Appropriate safeguards must be used when working on or near or bringing any conductive object on or near live electrical power lines or energized equipment.

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

INDICATING TYPE

TUBULAR SECONDARY

FUSES

Indicating type tubular secondary fuses protect transformers and capacitors from secondary overloads and faults. Each secondary fuse has a spring locked red plastic flag which springs out from the cartridge when the fuse link melts, indicating an outage.

Fuses are available with insulated or non-insulated leads. UNIVERSAL ADAPTER

ASSEMBLIES

This universal adapter assembly will adapt Fit-All fuse links for use in the cutouts that have bolt-type cable con-nections to connect the upper as well as the lower cable. Note from the table that only five sizes are required to adapt to any type fuse.

TABLE 5

Ordering Information for Indicating Type Tubular Secondary Fuses

Figure 7.

Tubular secondary fuses.

Figure 8.

Universal Adapter assemblies.

Catalog Numbers Current Tinned Insulated

Rating (A) Leads Leads

10 8316 8316-5 15 8317 8317-5 20 8318 8318-5 25 8319 8319-5 30 8320 8320-5 40 8321 8321-5 50 8322 8322-5 60 8323 8323-5 75 8324 8324-5 100 8325 8325-5 125 8326 8326-5 150 8327 — 175 8328 — 200 8329 — 300 11405 —

TABLE 6

U-Adapter Assemblies*

For Types KS, X, K ,T and 200 Fuses

Current Rating (A) Catalog Number

1 /3-25 14036 30-50 14036-1 65-100 14036-2 125-150 14036-3 175-200 14036-4

TABLE 7

U-Adapter Assemblies*

For Type QA Fuse

Current Rating (A) Catalog Number

1 -25 14037 30-50 14037-1 60-100 14037-2 125-150 14037-3 175-200 14037-4

* 10" length for all ampere ratings * 10" length for all ampere ratings

Kearney™ Fuse Links

– Flag in operated position

– Flag in operational position

DUAL ELEMENT WEAK

LINKS

Kearney Dual Element Weak Link (DEWL) Under-Oil Fuses are available in the following ratings: 5 kV, 8.3 kV, 15 kV, 23 kV; 5 thru 70 A. They can be sized for complete fault response, including secondary cable dig-ins.

Following are features of the Kearney Weak Link:

■ Closely approximates ANSI safe loading curve for transformers when used to monitor transformer loads.

■ Clears at 145°C, preventing thermal runaway conditions.

■ Differentiates between load and fault outages permitting accurate field troubleshooting analysis.

■ Has high surge withstand capability.

■ Ideal for establishing composite fusing with back-up current limiting fuses.

■ Has superior sensitivity when compared with a secondary breaker.

■ Slower T/C characteristics permit use of lower ampere rated line fuses.

■ Extremely economical.

■ Common fusing system for all kVA ratings.

The Kearney line of Dual Element Fuses has been expanded to trans-former Weak Links. This design has a slower speed ratio than the single element types and more nearly approximates the slope of the ANSI safe loading curve for transformers.

This characteristic lends itself well when sizing fuses to monitor transformer loads and performs a function similar to a secondary breaker.

The DEWL is designed to have a high surge current withstand capability.

The user is not forced to increase the desired ampere rating as a result of high magnetizing inrush currents or lightning surges. As a matter of interest, some users choose a safe minimum fuse size which is capable of sensing secondary dig-ins for direct buried aluminum cables. The industry recognizes that this is not feasible with secondary breakers and conventional weak links.

The slower DEWL characteristic per-mits minimum upstream fusing where coordination of series devices might otherwise be difficult. As is indicated later, the slow speed of the DEWL TC curves combines best with the fast speed of the current-limiting fuses to form a desirable composite fusing scheme. This provides a minimum crossover area for positive fuse selec-tion and enables the weak link to sense faults external to the transformer and low internal faults. Since most faults are external, only the inexpensive weak link need be replaced, preserving the integrity of the back up current-limiting fuse.

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

One of the two elements in the DEWL is a eutectic metal which will melt at 145°C. Therefore, if the transformer top oil temperature reaches this level the fuse will melt and operate. This is beneficial since this temperature would be indicative of a possible thermal runaway condition.

In an effort to simplify the determination of the DEWL fuse’s overload capability, a family of curves was developed (Figure 9). They show the loading effects on top oil temperatures which in turn affects the fuse loading char-acteristic. The transformer loading curves assume a preload condition of 90°C top oil and the overload conditions were extracted from curves used for secondary breaker calibrations.

The values may be conservative since the fuse curves are plotted to minimum, the fuse may not physically be located exactly near the top oil hot spot and most transformers would generally have a lower preload condition. The curves were plotted for long term overload limit capability 15± hours from which a short term overload limit can easily be determined. The NELPA load cycle with a 3 hour peak is considered a short term overload condition.

The DEWL is available in the conven-tional style weak link fiberglass rein-forced “Horn Fiber” lined tube or the bay-o-net style with “Teflon” tube. The fuses are available in sizes 5 through 70 A at maximum voltages of 5, 8.3, 15 and 23 kV. The standard DEWL interrupting capability is 3.5 kA @ 8.3 kV, 2 kA @ 15.5 kV, 1.0 kA @ 23 kV, and the bay-o-net type performs at the bay-o-net rating.

LOADING GUIDE

Purpose To provide a simplified means for determining the upper limit of cyclic loading for all DEWL types in a varying oil ambient temperature environment.

Curves Transformer overload curves (increasing slope) effecting top oil temperatures superimposed on the DEWL melting curves (decreasing slope) in a variable top oil temperature environment.

Application

■ Locate transformer full load current on the 1 PU loading ordinate and follow along appropriate loading curve (interpolate) to the point of intercept on the appropriate DEWL curve - Read the long term (LT) 15± hour peak loading cycle limit by dropping vertically from this point.

■ Short term (ST) 3 hour peak loading cycle limit may be calculated from the (LT) values as follows:

ST = 1 + 2 (LT-1)

■ May safely add one tenth PU to LT obtained for padmounts 1Ø/3Ø respectively 25/75, 37/112, 50/150 and dual ratio or tap changer type units due to their relatively large tank size.

Note: Any thermal runaway is pre-vented because the DEWL will melt and clear for 145°C oil temperatures.

10 12 14

PER UNIT LOADING LT

16 18

14012010080604020

#70°

#60°

#50°

#35°

#30°

#25°

#15°

#12°

#8°

#6° #5°

FU

LL

L O

A D

C U

R R

E N

T

A M

P E

R E

S

P R

IM

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R Y

C U

R R

E N

T C

U R

R E

N T

A

M P

E R

E S

*PARALLEL FUSES TOP OIL TEMP __ °C

K-SEC 030

Figure 9.

Loading Guide for all DEWL Types, all voltages.

This product was compiled by:

TSgt Russell C. Wells Vandenberg AFB, California

FA461019RA029 - ATTACHMENT

se ll W ell s

TWO FUSE SYSTEM

COORDINATION

Expulsion fuses have advantages at low fault current levels but have great limitations at high fault current levels.

Conversely, current-limiting fuses have limitations at low faults but enormous advantages at high fault current levels.

The two fuse system combines the best of both for the first truly “full range” system fault protection. This benefit applies even if system faults increase in the future. A pressure relief device is complimentary to the fuse protection system.

Figure 10 illustrates a typical distribu-tion system. If only a current-limiting fuse were used, full coordination could not be obtained with upstream devices. Adding a DEWL fuse provides an effective composite protective curve. This indicates how the “Back-up CLF” can be used effectively with existing expulsion fusing schemes without upsetting system coordination.

The back-up fuse only operates for fault conditions at and beyond the intercept of the expulsion and CLF curves. Since most faults are of a low magnitude the inexpensive expulsion fuse will clear and leave the CLF intact for operation at high fault currents. It should be understood that the back-up fuse can be used with any expulsion fuse whether in a cutout or a weak link. The text will make reference to the Dual Element Weak Link (DEWL) since more applications will fall in this category.

Selective crossing of the composite two fuse curves provides additional benefits. Figure 10 shows a cross-over current value (TC/DEWL and MM/CLF) which is greater than the Let-Thru Current of a bolted secondary fault.

Access under these conditions is not necessary since a CLF operation would indicate a serious internal fault requiring a transformer replacement in any case.

This now permits locking the CLF in the transformer, the least cost approach.

Since the fuse is not influenced by overvoltages due to possible secondary delta load, the CLF voltage rating for three phase application is a L-G value, an additional cost savings.

(Note, however, that the expulsion fuse must have a L-L voltage rating because of the secondary influence).

Recommended fusing combinations are available in the tables in this section.

The selections are for use with Kearney's DEWL and oil immersible back-up CLF. Recommendations are made for both padmount and pole mount units; the pole mount CLF sizes are slightly larger to protect against damage from lightning surges.

Figure 10.

100 A back-up current-limiting oil immersible fuse.

Kearney™ Fuse Links

This product was compiled by:

TSgt Russell C. Wells se ll W ell s

ORDERING INFORMATION

AND DIMENSIONS

K-SEC 030

Catalog Max. Ampere Dimensions (inches) Number kV Ratings X Y Z

8.3 and 15 kV

124084-13 NA 3-7/8 4-7/16 3-3/4

124084-14 15.5 NA

124084-15 NA

124084-16 NA

Note: NA-Not Applicable (See 124030 TC Curves)

Catalog Max. Ampere ** Number kV Ratings

124080-5 5 124080-6 6 124080-8 22 8 124080-12 12 124080-15 15

124080…