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Varistor Products

High Energy Industrial

Power Dissipation Ratings

Should transients occur in rapid succession, the average power

dissipation result 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 must be derated as shown

in Figure 1.

Transient V-I Characteristics Curves

FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM

100

90

50

10

T

TIME

T = Time From 10% to 90% of Peak

Example: For an 8/20µs Current Waveform:

1000

10000

0.001

0.01

0.1

1

10

100

10000

100000

TMOV34S

TA = -55 C to 85C

Current - AMPS

Voltage

Volts

V751

V681

V661

V571

V551

V511

V391

V351 V331 V321

V271

V251 V201 V181

V151

V141

V111

V131

V301

V481

V441

V421

100

1000

HB34, HF34 and HG34 Varistor Series

FIGURE 3. CLAMPING VOLTAGE FOR HB34, HF34 and HG34 SERIES