100

1000

10000

10000

0.001

0.01

0.1

1

10

100

1000

10000

100000

Maximum Clamping Voltage

HA40 Series

110 to 750V AC Rating

TA = -55 C to 85C

Current - (A)

V751

V571

V551

V511

V481

V441

V421

V391

V351

V111

V131

V141

V151

V681

V331

V321

V301

V271

V251

V201

V181

V661

93

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Varistor Products

2

HA Varistor Series

High Energy Industrial

Power Dissipation Ratings

Should transients occur in rapid succession, the average power dissipa-

tion 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. Furthermore, the operating values need to be

derated at high temperatures as shown in Figure 1. Because varistors

can only dissipate a relatively small amount of average power they are,

therefore, not suitable for repetitive applications that involve substantial

amounts for average power dissipation.

Transient V-I Characteristics Curves

100

90

80

70

60

50

40

30

20

10

0

-55

50

60

70

80

90

100

110

120

130

140 150

FIGURE 1. CURRENT, ENERGY AND POWER DERATING

CURVE

FIGURE 2. PEAK PULSE CURRENT WAVEFORM

100

90

50

10

T

TIME

T = Time From 10% to 90% of Peak

Example: For an 8/20µs Current Waveform:

100

1000

10000

0.001

0.01

0.1

1

10

100

1000

10000

100000

Current (A)

TA = -55 C to 85C

V681CA32

V751CA32

V481CA32

V441CA32

V421CA32

V391CA32

V571CA32

V661HA32

V551CA32

V511CA32

V301CA32

V331CA32

V321CA32

V351CA32

V271CA32

V251CA32

V201CA32

V181CA32

V151CA32

V141CA32

V131CA32

C111CA32

Maximum Clamping Voltage

HA32 Series

110 to 750V AC Rating

FIGURE 3. MAXIMUM CLAMPING VOLTAGE (V111HA32 - V751HA32)

FIGURE 4. MAXIMUM CLAMPING VOLTAGE (V111HA40 - V751HA40)

Current (A)