V250LA20C - Harris Semiconductor - searchdatasheet.com

SEMICONDUCTOR

4-26

“C” III Series

Radial Lead Metal-Oxide Varistors

age transients in the AC power network can be detrimental

to the associated line equipment. Such transient occur-

rences may cause product failure and the subsequent faulty

operation of the electrical systems. This special version of

the Harris 14mm and 20mm LA series of metal oxide varis-

tors is also available with 10mm lead spacing, tape and reel,

and in a variety of crimped and trimmed lead forms.

Features

• Recognized as “Transient Voltage Surge Suppressors” to UL 1449;

File # E75961

• Recognized as “Transient Voltage Surge Suppressors” to CSA

C22.2, No. 1; File # LR91788

• High Energy Absorption Capability WTM . . . . . . . . 45J to 210J (2ms)

• High Peak Pulse Current Capability ITM . . . .6000A to 9000A (8/20µs)

• Wide Operating Voltage Range VM(AC)RMS . . . . . . . . . . . 130V to 320V

• Available in Tape and Reel for Automatic Insertion; Also Available

with Crimped and/or Trimmed Lead Styles

June1995

“C” III SERIES

Absolute Maximum Ratings For ratings of individual members of a series, see Device Ratings and Speciﬁcations chart

“C” III SERIES UNITS

Continuous:

Steady State AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130 to 320 V

Transients:

Single-Pulse Peak Current (ITM) 8/20µs Wave (See Figure 2) . . . . . . . . . . . . . . . . . . . . . . . . . . .

Single-Pulse Energy Range (WTM) 2ms Rectangular Wave . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6000 to 9000

45 to 210 A

Maximum Temporary Overvoltage of VM(AC), (5 Minutes Duration). . . . . . . . . . . . . . . . . . . . . . . . . . 130 (+25oC)

120 (+125oC) %

Operating Ambient Temperature Range (TA). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +85 oC

Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to +125 oC

Temperature Coefficient (αV) of Clamping Voltage (VC) at Specified Test Current. . . . . . . . . . . . . . <0.01 %/oC

Description

The expanded version of the LA series of metal-oxide varis-

tors, designation “C” III series, consists of AC line voltage

rated MOVs with extremely high current and energy han-

dling capabilities. This new “C” III series of MOVs was pri-

marily designed for the transient voltage surge suppressor

(TVSS) environment. They provide the increased level of

protection now deemed to be necessary for the transients

expected in this environment. The occurrence of high volt-

File Number 3540.3

4-27

Speciﬁcations “C” III Series

“C” III Series Ratings

MODEL

NUMBER DEVICE

MARKING

MAXIMUM RATINGS (+85oC)

CONTINUOUS TRANSIENT

MAXIMUM VRMS

VM(AC)

(V)

WITHSTANDING

ENERGY (2ms)

WTM ()

(J)

PEAK CURRENT (8/20µs)

ITM1 1 PULSE

(A) ITM2 2 PULSES

(A)

V130LA10C

V130LA20C

V130LA20CX325

130L10C

130L20C

130LA20CX325

130

6000

9000

5000

7000

V140LA10C

V140LA20C

V140LA20CX340

140L10C

140L20C

140L20CX340

140

100

6000

9000

5000

7000

V150LA10C

V150LA20C

V150LA20CX360

150L10C

150L20C

150L20CX360

150

110

6000

9000

5000

7000

V175LA10C

V175LA20C

V175LA20CX425

175L10C

175L20C

175L20CX425

175

120

6000

9000

5000

7000

V230LA20C

V230LA40C

V230LA40CX570

230L20C

230L40C

230L40X570

230

160

6000

9000

5000

7000

V250LA20C

V250LA40C

V250LA40CX620

250L20C

250L40C

250L40CX620

250

100

170

6000

9000

5000

7000

V275LA20C

V275LA40C

V275LA40CX680

275L20C

275L40C

275L40CX680

275

110

190

6000

9000

5000

7000

V300LA20C

V300LA40C

V300LA40CX745

300L20C

300L40C

300L40CX745

300

120

210

6000

9000

5000

7000

V320LA20C

V320LA40C 320L20C

320L40C 320

320 200

200 6000

9000 5000

7000

“C” III Series Speciﬁcations

MODEL

NUMBER

MODEL SIZE

DISC

DIAMETER

(mm)

SPECIFICATIONS (+25oC)

VARISTOR VOLTAGE AT

1mA DC TEST CURRENT

MAXIMUM CLAMPING

VOLTAGE

(8/20µs) DUTY CYCLE SURGE

RATING

VN MIN

(V) VN MAX

(V) VC

(V) Ip

(A)

3kA

(8/20µs)

# PULSES

750A

(8/20µs)

# PULSES

V130LA10C

V130LA20C

V130LA20CX325

184

228

220

340

325

100

120

V140LA10C

V140LA20C

V140LA20CX340

198

242

230

360

340

100

120

V150LA10C

V150LA20C

V150LA20CX360

212

268

243

395

360

100

120

V175LA10C

V175LA20C

V175LA20CX425

247

303

285

455

425

100

120

4-28

“C” III Series

FIGURE 1. CURRENT, ENERGY AND POWER DERATING

CURVE

100

-55 50 60 70 80 90 100 110 120 130 140 150

AMBIENT TEMPERATURE (oC)

PERCENT OF RATED VALUE

Power Dissipation Ratings

The metal oxide varistor is designed to absorb voltage

transients of relatively short durations, not continuous over

voltage. Therefore, unless transients occur in rapid

succession, a continuous power dissipation capability is

not an applicable design requirement for a varistor. Under

this condition, the average power dissipation required is

simply the energy (watt-seconds) per pulse times the

number of pulses per second. The power so developed

must be within the speciﬁcations shown on the Device

Ratings and Speciﬁcations table for the speciﬁc device.

The operating values of a MOV need to be derated at high

temperatures as shown in Figure 1. Because varistors only

dissipate a relatively small amount of average power they

are not suitable for repetitive applications that involve

substantial amounts of average power dissipation.

FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM

100

O1T

T1T2

TIME

PERCENT OF PEAK VALUE

O1 = Virtual Origin of Wave

T = Time From 10% to 90% of Peak

T1 = Virtual Front time = 1.25 •t

T2 = Virtual Time to Half Value (Impulse Duration)

Example: For an 8/20µs Current Waveform:

8µs = T1 = Virtual Front Time

20µs = T2 = Virtual Time to Half Value

V230LA20C

V230LA40C

V230LA40CX570

324

396

384

595

570

100

120

V250LA20C

V250LA40C

V250LA40CX620

354

429

413

650

620

100

120

V275LA20C

V275LA40C

V275LA40CX680

389

473

453

710

680

100

120

V300LA20C

V300LA40C

V300LA40CX745

420

517

490

775

745

100

120

V320LA20C

V320LA40C 14

20 462

462 565

565 850

850 50

100 10

20 80

120

NOTE: Average power dissipation of transients not to exceed 0.6W and 1W for model sizes 14mm and 20mm, respectively

“C” III Series Speciﬁcations (Continued)

MODEL

NUMBER

MODEL SIZE

DISC

DIAMETER

(mm)

SPECIFICATIONS (+25oC)

VARISTOR VOLTAGE AT

1mA DC TEST CURRENT

MAXIMUM CLAMPING

VOLTAGE

(8/20µs) DUTY CYCLE SURGE

RATING

VN MIN

(V) VN MAX

(V) VC

(V) Ip

(A)

3kA

(8/20µs)

# PULSES

750A

(8/20µs)

# PULSES

4-29

“C” III Series

Transient V-I Characteristics Curves

FIGURE 3. MAXIMUM CLAMPING VOLTAGE FOR V130LA10C

TO V320LA20C FIGURE 4. MAXIMUM CLAMPING VOLTAGE FOR V130LA20C

TO V320LA40C

FIGURE 5. MAXIMUM CLAMPING VOLTAGE FOR V130LA20CX325 TO V300LACX745

Pulse Rating Curves

FIGURE 6. REPETITIVE SURGE CAPABILITY FOR V130LA10C

TO V320LA20C FIGURE 7. REPETITIVE SURGE CAPABILITY FOR V130LA20C

TO V320LA40C

1,000

100

PEAK AMPERES (A)

MAXIMUM PEAK VOLTAGE (V)

V175LA10C

V150LA10C

V140LA10C

V130LA10C

MODEL SIZE = 14mm

TA = -55oC TO +85oC

130 TO 320VM(AC) RATING

10-2 10-1 100101102103104

10-3

2,000

500

300

200

V300LA20C

V275LA20C

V250LA20C

V230LA20C

V320LA20C

1,000

100

MAXIMUM PEAK VOLTAGE (V)

MODEL SIZE = 20mm

TA = -55oC TO +85oC

130 TO 320VM(AC) RATING

PEAK AMPERES (A)

10-2 10-1 100101102103104

10-3

V175LA20C

V150LA20C

V140LA20C

V130LA20C

V300LA40C

V275LA40C

V250LA40C

V230LA40C

V320LA40C

500

300

200

2,000

1,000

100

PEAK AMPERES (A)

MAXIMUM PEAK VOLTAGE (V)

V175LA20CX425

V150LA20CX360

V140LA20CX340

V130LA20CX325

MODEL SIZE = 20mm

TA = -55oC TO +85oC

130 TO 300VM(AC) RATING

10-2 10-1 100101102103104

10-3

V300LA40CX745

V275LA40CX680

V250LA40CX620

V230LA40CX570

10,000

1,000

100

110 100 1,000 10,000

SURGE IMPULSE DURATION (µs)

RATED PEAK SURGE CURRENT (A)

10 12

102

103

104

INDEFINITE

SURGE

CAPABILITY

MODEL SIZE = 14mm

TA = -55oC TO +85oC

130 TO 320VM(AC) RATING

10,000

1,000

100

110 100 1,000 10,000

SURGE IMPULSE DURATION (µs)

RATED PEAK SURGE CURRENT (A)

103

104

INDEFINITE

SURGE

CAPABILITY

MODEL SIZE = 20mm

TA = -55oC TO +85oC

130 TO 320VM(AC) RATING

102

4-30

“C” III Series

Tape and Reel Speciﬁcation

SYMBOL DESCRIPTION

MODEL SIZE

14mm 20mm

P Pitch of Component 25.4 ± 1.0

P0Feed Hole Pitch 12.7 ± 0.2

P1Feed Hole Center to Pitch 2.60 ± 0.7

P2Hole Center to Component

Center 6.35 ± 1.0

F Lead to Lead Distance 7.50 ± 0.8

h Component Alignment 2.00 Max

W Tape Width 18.25 ± 0.75

W0Hold Down Tape Width 6.00 ±

0.3 12.0 ±

0.3

W1Hole Position 9.125 ± 0.625

W2Hold Down Tape Position 0.5 Max

H Height From Tape Center

To Component Base 19.0 ± 1.0

H0Seating Plane Height 16.0 ± 0.5

H1Component Height 40 Max 46.5

Max

D0Feed Hole Diameter 4.0 ± 0.2

t Total Tape Thickness 0.7 ± 0.2

L Length of Clipped Lead 12.0 Max

p Component Alignment 3o Max

Tape and Reel Data

• Conforms to ANSI and EIA Speciﬁcations

• Can be supplied to IEC publication 286-2

• Radial devices on tape and reel are supplied with either

crimped leads, straight leads, or under-crimped leads.

Tape and Reel Ordering Information

• Crimped leads are standard on LA types supplied in tape

and reel and are denoted by the model letter “T”. Also, in

tape and reel, model letter “S” denotes straight leads and

letter “U” denotes special under-crimped leads.

Example:

Shipping Quantity

Package Outline Dimensions

STANDARD

MODEL CRIMPED

LEADS STRAIGHT

LEADS

UNDER

CRIMP

LEADS

V130LA20C V130LT20C V130LS20C V130LU20C

DEVICE

SIZE

QUANTITY PER REEL

“T” REEL “S” REEL “U” REEL

14mm 500 500 500

20mm 500 500 500

SYMBOL

VARISTOR MODEL SIZE

14mm 20mm

MIN MAX MIN MAX

A 13.5

(0.531) 20

(0.787) 17.5

(0.689) 26.5

(1.043)

ØD 13.5

(0.531) 17

(0.669) 17.5

(0.689) 23

(0.906)

e 6.5

(0.256) 8.5

(0.335) 6.5

(0.256) 8.5

(0.335)

e1 1.5

(0.059) 3.5

(0.138) 1.5

(0.059) 3.5

(0.138)

E-

5.6

(0.220) -

-5.6

(0.220)

Øb 0.76

(0.030) 0.86

(0.034) 0.76

(0.030) 0.86

(0.034)

Dimensions are in millimeters (inches)

NOTE: 10mm lead spacing also available. See additional lead style

options.

4-31

“C” III Series

Additional Lead Style Options

Radial lead types can be supplied with combination pre-

formed crimp and trimmed leads. This option is supplied to

the dimensions shown below.

*Seating plane interpretation per IEC-717

• To order this crimped and trimmed lead style, the standard

radial type model number “LA” is changed to the model

number “LC”. This option is supplied in bulk only.

Example:

• For 10 ± 1mm lead spacing on 20mm units only; append

standard model numbers by adding “X10” sufﬁx.

Example:

• For other lead style variations to the above, please contact

Harris Semiconductor Power Marketing

SYMBOL

VARISTOR MODEL SIZE

14mm 20mm

MIN MAX MIN MAX

A - 24.5

(0.96) -31

(1.22)

LTRIM 2.41

(0.095) 4.69

(0.185) 2.41

(0.095) 4.69

(0.185)

NOTE: Dimensions are in millimeters (inches)

STANDARD MODEL ORDER AS

V130LA20C V130LC20C

STANDARD MODEL ORDER AS

V130LA20C V130LA20CX10

The Origins of Surge Overvoltages

There are a wide variety of transient overvoltage

environments, each with radically different levels of

exposure. Transients may be caused by lightning, which can

inject very high currents into the electrical system, or by

switching transients. Lightning strikes usually occur to the

primary transmission lines with resulting coupling to the

secondary line through mutual inductive or capacitive

coupling. Even a lightning hit that misses the primary AC line

can induce substantial voltage onto the primary conductors,

triggering lightning arresters and thus creating transients.

Switching transients, while of a lower magnitude than light-

ning, occur more frequently and thus are of a greater threat

to the AC system. Switching transients may result from fuse

blowing, capacitor bank switching, fault clearing or grid

switching.

Field studies and laboratory investigation of residential and

industrial low power AC voltage systems have shown that

the amplitude of a transient is proportional to the rate of its

occurrence, i.e. lower magnitude transients occur most

often. Governing bodies, in particular IEC, UL, IEEE and

ANSI have established guidelines on the transient

environment one may expect to encounter in a low voltage

AC power system. Table 1 reﬂects the surge voltages and

currents deemed to represent the indoor environment.

LOCATION CATEGORY TRANSIENT WAVEFORM/

MAGNITUDE

A Long Branch Circuits

and Outlets 0.5µs

100kHz 6kV

200A

B Major Feeders and

Short Branch Circuits 1.2/50µs

8/20µs6kV

3kA

0.5µs

100kHz 6kV

500A

4-32

“C” III Series

“C” III MOV Series

The new “C” III series of Harris radial MOVs represent the

third generation of improvements in device performance and

characteristics. The technology effort involved in the devel-

opment of this new series concentrated on extending the

existing performance and capability of the Harris second

generation of metal oxide varistors.

The characteristics of greatest importance for a metal oxide

varistor in an AC surge environment are the peak current,

energy handling, repetitive surge and temporary over-volt-

age capabilities. The focus of the design effort was on

improving these characteristics and therefore offering the

maximum protection presently available to the end user.

The new “C” III series are designed to survive the harsh

environments of the AC low-power indoor environment.

Their much improved surge withstand capability is well in

excess of the transients expected in the AC mains environ-

ment. Further design rules for the development of the “C” III

series included considerations of the expected steady state

operating conditions and the repetitive surge environment.

Investigation of the AC low-power indoor environment show

that most transients occur where the power enters the build-

ing and at major feeders and short branch circuits. Surges

recorded at this service entrance, location Category B from

C62.41-1992, may be both oscillatory and unidirectional in

nature. The typical “lightning surge” has been established as

a 1.2/50µs voltage wave and a 8/20µs current wave. A short

circuit current of 3000A and open circuit voltage 6000V are

the expected worst case transients at this location.

TEST REFERENCE

STANDARD TEST

CONDITIONS TEST

RESULTS

Surge

Current UL 1449

IEEE/ANSI

C62.41

9000A

(8/20µs)

1 Pulse

0/165

IEC 1051 7000A

(8/20µs)

2 Pulses

0/105

3000A

(8/20µs)

20 Pulses

0/75

750A

(8/20µs)

120 Pulses

0/65

Surge

Energy UL 1449

IEEE/ANSI

C62.41

IEC 1051

90J

(2ms)

1 Pulse

0/125

Operating

Life Mil-Std-202

Method 204D 125oC, 1000

Hours, Rated

Bias Voltage

0/180

Temporary

Overvoltage N/A 120% Maxi-

mum Rated

Varistor

Voltage For 5

minutes

0/70

The further into the facility one goes, the lower the magni-

tude of the transients encountered. ANSI/IEEE C62.41 dif-

ferentiates between the service entrance and the interior of a

facility. Per this speciﬁcation, the internal location or long

branch circuits and outlets are classiﬁed as Location Cate-

gory A. The transients encountered here have oscillatory

waveshapes with frequency ranges from 5kHz to 500kHz;

with 100kHz deemed most common. Transients of the mag-

nitude of 500A are expected in this location.

Reliability Performance of “C” III Series

The electrical ratings of the “C” III series of MOVs are con-

servatively stated. Samples of these devices have been

tested under additional stresses, over and above those

called out in the datasheet. The results of this testing show

an enhanced device performance.

The series of stress tests to which the units were subjected

are a combination of electrical, environmental and mechani-

cal tests. A summary of the reliability tests performed on the

“C” III series are described in Table 2

AC Bias Reliability

The “C” III series of metal oxide varistors was designed for

use on the AC line. The varistor is connected across the AC

line and is biased with a constant amplitude sinusoidal volt-

age. It should be noted that the deﬁnition of failure is a shift

in the nominal varistor voltage (VN) exceeding ±10%.

Although this type of varistor is still functioning normally after

this magnitude of shift, devices at the lower extremities of VN

tolerance will begin to dissipate more power.

Because of this possibility, an extensive series of statistically

designed tests were performed to determine the reliability of

the “C” III type of varistor under AC bias combined with high

levels of temperature stress. To date, this test has generated

over 50,000 device hours of operation at a temperature of

+125oC, although only rated at +85oC. Changes in the nomi-

nal varistor voltage, measured at 1mA, of less than 2% have

been recorded (Figure 8).

Transient Surge Current/Energy

Capability

The transient surge rating serves as an excellent ﬁgure of

merit for the “C” III suppressor. This inherent surge handling

capability is one of the new “C” III suppressor’s best fea-

tures. The enhanced surge absorption capability results from

improved process uniformity and enhanced construction.

The homogeneity of the raw material powder and improved

control over the sintering and assembly processes are con-

tributing factors to this improvement.

In the low power AC mains environment, industry governing

bodies (UL, IEC, NEMA and IEEE) all suggest that the worst

case surge occurrence will be 3kA. Such a transient event

may occur up to ﬁve times over the equipment life time

(approximately 10 years). While the occurrences of ﬁve 3

4-33

“C” III Series

kiloamps transients is the required capability, the conserva-

tively rated, repetitive surge current for the “C” III series is 20

pulses for the 20mm units and 10 pulses for the 14mm

series.

As a measure of the inherent device capability, samples of

the 20mm V130LA20C devices were subjected to a worst

case repetitive transient surges test. After 100 pulses, each

of 3kA, there was negligible change in the device character-

istics. Changes in the clamping voltage, measured at 100

amps, of less than 3% were recorded (Figure 9). Samples of

the 14mm Series V175LA20C were subjected to repetitive

surge occurrences of 750A. Again, there was negligible

changes in any of the device characteristics after 250 pulses

(Figure 10). In both cases the inherent device capability is

far in excess of the expected worst case scenario.

Terms and Descriptions

Rated AC Voltage (VM(AC)RMS)

This is the maximum continuous sinusoidal voltage which

may be applied to the MOV. This voltage may be applied at

any temperature up to the maximum operating temperature

of +85oC.

Maximum Non-Repetitive Surge Current (ITM)

This is the maximum peak current which may be applied for

an 8/20µs impulse, with rated line voltage also applied, with-

out causing device failure. (See Figure 2)

Maximum Non-Repetitive Surge Energy (WTM)

This is the maximum rated transient energy which may be

dissipated for a single current pulse at a speciﬁed impulse

and duration (2ms), with the rated VRMS applied, without

causing device failure.

Nominal Voltage (VN(DC))

This is the voltage at which the device changes from the off

state to the on state and enters its conduction mode of oper-

ation. This voltage is characterized at the 1mA point and has

speciﬁed minimum and maximum voltage levels.

Clamping Voltage (VC)

This is the peak voltage appearing across the MOV when

measured at conditions of speciﬁed pulse current amplitude

and speciﬁed waveform (8/20µs)

FIGURE 8. HIGH TEMPERATURE OPERATING LIFE 125oC

FOR 1000 HOURS AT RATED BIAS

FIGURE 9. TYPICAL REPETITIVE SURGE CURRENT CAPA-

BILITY OF “C” III SERIES MOVs

FIGURE 10. TYPICAL REPETITIVE SURGE CURRENT CAPA-

BILITY OF “C” III SERIES MOVs

300

250

200

150

1000 100 200 300 400 500 600 700 800 900 1000 1100

TIME (HOURS)

VNOM AT 1mA (V)

V130LA20C

500

450

400

350

3000 102030405060708090100110120

NUMBER OF SURGES

(RATED FOR 20 SURGES)

CLAMPING VOLTAGE AT 3kA

V130LA20C

3kA (8/20µs)

600

550

500

450

400

350

3000 50 100 150 200 250 300

NUMBER OF SURGES

(RATED FOR 80 SURGES)

CLAMPING VOLTAGE AT 750A

V175LA20C

750A (8/20µs)