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Varistor products, Radial leaded varistors > atmov series, Lv ultramo v – Littelfuse ATMOV Varistor Series User Manual

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Varistor Products

© 2014 Littelfuse, Inc.

Specifications are subject to change without notice.
Revised: 02/18/14

3

Radial Leaded Varistors > ATMOV Series

LV UltraMO

V

S

eries

Current Energy and Power Dissipation Ratings

100

90

80

70

60

50

40

30

20

10

0

-55

50

60

70

80

90

100 110

120 130 140 150

AMBIENT TEMPERATURE (

o

C)

PERCENT OF

RA

TED

VALUE

Figure 1A - Power Derating for Epoxy Coated

FIGURE 1. CURRENT, ENERGY AND POWER DERATING

CURVE

100

90

80
70

60

50
40

30

20

10

0

-55

50

60

70

80

90

100 110 120 130 140 150

AMBIENT TEMPERATURE (

o

C)

PERCENT OF

RA

TED

VALUE

Figure 1B - Power Derating for Phenolic Coated

t

1

t

2

100

50

0

O

1

TIME

PERCENT OF PEAK

VALUE

t

Peak Pulse Current Test Waveform for Clamping Voltage

0

1

= Virtual Origin of Wave

t = Time from 10% to 90% of Peak
t

1

= Virtual Front Time = 1.25 x t

t

2

= Virtual Time to Half-Value (Impulse Duration)

Example - For an 8/20

µs Current Waveform:

8µs = t

1

= Virtual Front Time

20µs = t

2

= Virtual Time to Half-Value

Figure 2: Peak Pulse Current Test Waveform for Clamping Voltage

For applications exceeding 85ºC ambient temperature,
the peak surge current and energy ratings must be
reduced as shown below.

For applications exceeding 125ºC ambient temperature,
the peak surge current and energy ratings must be
reduced as shown below.