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Low to Medum Voltage, Radial Lead
ZA Varistor Series
The ZA Series of transient voltage surge suppressors are radial-lead
varistors (MOVs) designed for use in the protection of low and medium-
voltage circuits and systems. Typical applications include motor control,
telecom, automotive systems, solenoid, and power supply circuits to
protect circuit board components and maintain data integrity.
These devices are available in five model sizes: 5mm, 7mm, 10mm,
14mm and 20mm, and feature a wide VDC voltage range of 5.5V to 615V.
See ZA Series Device Ratings and Specifications table for part number
and brand information.
Features
•Wide Operating Voltage Range VM(AC)RMS . . . . . . . . . .4V to 460V
•DC Voltage Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5.5V to 615V
•No Derating Up to 85oCAmbient
•5Model Sizes Available . . . . . 5, 7, 10, 14, and 20mm
•Radial-Lead Package for Hard-Wired or Printed Circuit
Board Designs
•Available in Tape and Reel or Bulk Pack
•Standard Lead Form Options
AGENCY APPROVALS: Recognized under the components program of
Underwriters Laboratories. VDE certified.
AGENCY FILE NUMBERS: UL E135010, VDE 116895E.
®
V
DE
2
VARISTOR
PRODUCTS
Varistor Products
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ZA Varistor Series
Low to Medum Voltage, Radial Lead
Absolute Maximum Ratings For ratings of individual members of a series, see Device Ratings and Specifications chart.
Continuous:
Steady State Applied Voltage:
AC Voltage Range (VM(AC)RMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 to 460 V
DC Voltage Range (VM(DC)) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5.5 to 615 V
Transient:
Peak Pulse Current (ITM)
For 8/20µs Current Wave (See Figure 2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 to 6500 A
Single Pulse Energy Range (Note 1)
For 10/1000µs Current Wave (WTM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.1 to 52 J
Operating Ambient Temperature Range (TA)...............................................................-55 to85 oC
Storage Temperature Range (TSTG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -55 to125 oC
Temperature Coefficient (αV) of Clamping Voltage (VC)at Specified Test Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . <0.01 %/oC
Hi-Pot Encapsulation (Isolation Voltage Capability) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2500 V
(Dielectric must withstand indicated DC voltage for one minute per MIL-STD 202, Method 301)
Insulation Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1000 MΩ
CAUTION: Stresses above those listed in “Absolute Maximum Ratings” may cause permanent damage to the device. This is a stress only rating and operation of the device
at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Device Ratings and Specifications (Note 1)
ZA SERIES UNITS
PART
NUMBER
MODEL 
SIZE
DISC
DIA.(mm) BRAND
MAXIMUM RATING (85
o
C) SPECIFICATIONS (25
o
C)
CONTINUOUS TRANSIENT
VARISTOR VOLT-
AGE AT 1mA DC
TEST CURRENT
MAXIMUM 
CLAMPING 
VOLTAGE
8 x 20µs
TYPICAL
CAPACI-
TANCE
f = 1MHzV
RMS
V
DC
ENERGY 10
x1000µs
PEAK 
CURRENT 
8 x 20µs
V
M(AC)
V
M(DC)
W
TM
I
TM
V
NOM 
MIN
V
NOM
MAX V
C
I
PK
C
(V) (V) (J) (A) (V) (V) (A) (pF)
V8ZA05 5 Z08 4 5.5 0.1 50 6 11 30 1 1400
V8ZA1 7 08Z1 4 5.5 0.4 100 6 11 22 2.5 3000
V8ZA2 10 08Z2 4 5.5 0.8 250 6 11 20 5 7500
V12ZA05 5 Z12 6 8 0.14 50 9 16 37 1 1200
V12ZA1 7 12Z1 6 8 0.6 100 9 16 34 2.5 2500
V12ZA2 10 12Z2 6 8 1.2 250 9 16 30 5 6000
V18ZA05 5 Z18 10 14 0.17 100 14.4 21.6 36 1 1000
V18ZA1 7 18Z1 10 14 0.8 250 14.4 21.6 36 2.5 2000
V18ZA2 10 18Z2 10 14 1.5 500 14.4 21.6 36 5 5000
V18ZA3 14 18Z3 10 14 3.5 1000 14.4 21.6 36 10 11000
V18ZA40 20 18Z40 10 14 80 (Note 2) 2000 14.4 
(Note 3)
21.6 37 20 22000
V22ZA05 5 Z22 14 18 0.2 100 18.7 26 43 1 800
V22ZA1 7 22Z1 14 18 0.9 250 18.7 26 43 2.5 1600
V22ZA2 10 22Z2 14 18 2 500 18.7 26 43 5 4000
V22ZA3 14 22Z3 14 18 4 1000 18.7 26 43 10 9000
V24ZA50 20 24Z50 14 18
(Note 4)
100 (Note 2) 2000 19.2 
(Note 3)
26 43 20 18000
V27ZA05 5 Z27 17 22 0.25 100 23 31.1 53 1 600
V27ZA1 7 27Z1 17 22 1  250 23 31.1 53 2.5 1300
V27ZA2 10 27Z2 17 22 2.5 500 23 31.1 53 5 3000
V27ZA4 14 27Z4 17 22 5 1000 23 31.1 53 10 7000
V27ZA60 20 27Z60 17 22 120 (Note 2) 2000 23
(Note 3)
31.1 50 20 13000
Varistor Products
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Low to Medum Voltage, Radial Lead
ZA Varistor Series
Device Ratings and Specifications (Note 1) (Continued)
V33ZA05 5 Z33 20 26 0.3 100 29.5 38 65 1 500
V33ZA1 7 33Z1 20 26 1.2 250 29.5 36.5 65 2.5 1100
V33ZA2 10 33Z2 20 26 3 500 29.5 36.5 65 5 2700
V33ZA5 14 33Z5 20 26 6 1000 29.5 36.5 65 10 6000
V33ZA70 20 33Z70 21 27 150 (Note 2) 2000 29.5
(Note 3)
36.5 58 20 13000
V36ZA80 20 36Z80 23 31 160 (Note 2) 2000 32
(Note 3)
40 63 20 12000
V39ZA05 5 Z39 25 31 0.3 100 35 46 79 1 500
V39ZA1 7 39Z1 25 31 1.2 250 35 43 79 2.5 1100
V39ZA3 10 39Z3 25 31 3 500 35 43 76 5 2700
V39ZA6 14 39Z6 25 31 6 1000 35 43 76 10 6000
V39ZA20 20 39Z20 25 31 20 2000 35 43 76 20 12000
V47ZA05 5 Z47 30 38 0.4 100 42 55 93 1 400
V47ZA1 7 47Z1 30 38 1.8 250 42 52 93 2.5 800
V47ZA3 10 47Z3 30 38 4.5 500 42 52 93 5 2000
V47ZA7 14 47Z7 30 38 8.8 1000 42 52 93 10 4500
V47ZA20 20 47Z20 30 38 23 2000 42 52 93 20 11000
V56ZA05 5 Z56 35 45 0.5 100 50 66 110 1 360
V56ZA2 7 56Z2 35 45 2.3 250 50 62 110 2.5 700
V56ZA3 10 56Z3 35 45 5.5 500 50 62 110 5 1800
V56ZA8 14 56Z8 35 45 10 1000 50 62 110 10 3900
V56ZA20 20 56Z20 35 45 30 2000 50 62 110 20 10000
V68ZA05 5 Z68 40 56 0.6 100 61 80 135 1 300
V68ZA2 7 68Z2 40 56 3 250 61 75 135 2.5 600
V68ZA3 10 68Z3 40 56 6.5 500 61 75 135 5 1500
V68ZA10 14 68Z10 40 56 13 1000 61 75 135 10 3300
V68ZA20 20 68Z20 40 56 33 2000 61 75 135 20 10000
V82ZA05 5 Z82 50 68 2 400 73 97 135 5 240
V82ZA2 7 82Z2 50 68 4 1200 73 91 135 10 500
V82ZA4 10 82Z4 50 68 8 2500 73 91 135 25 1100
V82ZA12 14 82Z12 50 68 15 4500 73 91 145 50 2500
V100ZA05 5 Z100 60 81 2.5 400 90 117 165 5 180
V100ZA3 7 100Z 60 81 5 1200 90 110 165 10 400
V100ZA4 10 100Z4 60 81 10 2500 90 110 165 25 900
V100ZA15 14 100Z15 60 81 20 4500 90 110 175 50 2000
PART
NUMBER
MODEL
SIZE
DISC
DIA. (mm) BRAND
MAXIMUM RATING (85
o
C) SPECIFICATIONS (25
o
C)
CONTINUOUS TRANSIENT
VARISTOR VOLT-
AGE AT 1mA DC
TEST CURRENT
MAXIMUM
CLAMPING
VOLTAGE
8x 20µs
TYPICAL
CAPACI-
TANCE
f= 1MHzV
RMS
V
DC
ENERGY 10
x1000µs
PEAK
CURRENT
8x 20µs
V
M(AC)
V
M(DC)
W
TM
I
TM
V
NOM
MIN
V
NOM
MAX V
C
I
PK
C
(V) (V) (J) (A) (V) (V) (A) (pF)
2
VARISTOR
PRODUCTS
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ZA Varistor Series
Low to Medum Voltage, Radial Lead
Device Ratings and Specifications (Note1) (Continued)
V120ZA05 5 Z120 75 102 3 400 108 138 205 5 140
V120ZA1 7 120Z 75 102 6 1200 108 132 205 10 300
V120ZA4 10 120Z4 75 102 12 2500 108 132 200 25 750
V120ZA6 14 120Z6 75 102 22 4500 108 132 210 50 1700
V120ZA20 20 120Z20 75 102 33 6500 108 132 210 100 1500
V150ZA05 5 Z150 92 127 4 400 135 173 250 5 120
V150ZA1 7 Z051 95 127 8 1200 135 165 250 10 250
V150ZA4 10 150Z4 95 127 15 2500 135 165 250 25 600
†
V150ZA8 14 150Z8 95 127 20 4500 135 165 250 50 1400
V150ZA20 20 150Z20 95 127 45 6500 135 165 250 100 1000
V180ZA05 5 Z180 110 153 5 400 162 207 295 5 100
V180ZA1 7 180Z 115 153 10 1200 162 198 300 10 200
V180ZA5 10 180Z5 115 153 18 2500 162 198 300 25 500
V180ZA10 14 180Z10 115 153 35 4500 162 198 300 50 1100
V180ZA20 20 180Z20 115 153 52 6500 162 198 300 100 2400
V205ZA05 5 Z205 130 170 5.5 400 184 226 340 5 100
†
V220ZA05 5 Z220 140 180 6 400 198 253 360 5 90
†
V240ZA05 5 Z240 150 200 7 400 216 264 395 5 80
†
V270ZA05 5 Z270 175 225 7.5 400 243 311 455 5 70
†
V330ZA05 5 Z330 210 275 9 400 297 380 540 5 60
†
V360ZA05 5 Z360 230 300 9.5 400 324 396 595 5 55
†
V390ZA05 5 Z390 250 330 10 400 351 449 650 5 50
†
V430ZA05 5 Z430 275 369 11 400 387 495 710 5 45
†
V470ZA05 5 Z470 300 385 12 400 420 517 775 5 35
†
V620ZA05 5 Z620 385 505 13 400 558 682 1025 5 33
†
V680ZA05 5 Z680 420 560 14 400 610 748 1120 5 32
V715ZA05 5 Z715 440 585 15.5 400 643 787 1180 5 31
V750ZA05 5 Z750 460 615 17 400 675 825 1240 5 30
NOTES:
1. Average power dissipation of transients not to exceed 0.2W, 0.25W, 0.4W, 0.6W or 1W for model sizes 5mm, 7mm, 10mm, 14mm and 20mm,
respectively.
2. Energy rating for impulse duration of 30ms minimum to one half of peak current (auto load dump).
3. 10mA DC test current.
4. Also rated to withstand 24V for 5 minutes.
5. Higher voltages available, contact Littelfuse.
†
Also recognized to UL1449, “Transient Voltage Surge Suppressors” File #E75961.
PART
NUMBER
MODEL
SIZE
DISC
DIA. (mm) BRAND
MAXIMUM RATING (85
o
C) SPECIFICATIONS (25
o
C)
CONTINUOUS TRANSIENT
VARISTOR VOLT-
AGE AT 1mA DC
TEST CURRENT
MAXIMUM
CLAMPING
VOLTAGE
8 x 20µs
TYPICAL
CAPACI-
TANCE
f = 1MHzV
RMS
V
DC
ENERGY 10
x1000µs
PEAK
CURRENT
8 x 20µs
V
M(AC)
V
M(DC)
W
TM
I
TM
V
NOM
MIN
V
NOM
MAX V
C
I
PK
C
(V) (V) (J) (A) (V) (V) (A) (pF)
Varistor Products
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Low to Medum Voltage, Radial Lead
ZA Varistor Series
Power Dissipation Ratings
Should transients occur in rapid succession, 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. 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 of
average power dissipation.
FIGURE 1. CURRENT, ENERGY AND POWER DERATING 
CURVE
100
90
80
70
60
50
40
30
20
10
0
-55 50 60 70 80 90 100 110 120 130 140 150
AMBIENT TEMPERATURE (
o
C)
PERCENT OF RATED VALUE
FIGURE 2. PEAK PULSE CURRENT TEST WAVEFORM
100
90
50
10
O
1
T
T
1
T
2
TIME
PERCENT OF PEAK VALUE
O
1
= Virtual Origin of Wave
T = Time From 10% to 90% of Peak
T
1
= Virtual Front time = 1.25 • t
T
2
= Virtual Time to Half Value (Impulse Duration)
Example: For an 8/20µs Current Waveform:
8µs = T
1
= Virtual Front Time
20µs = T
2
= Virtual Time to Half Value
FIGURE 3. CLAMPING VOLTAGE FOR V8ZA05 - V68ZA05
600
500
400
300
200
100
90
80
70
60
50
40
30
20
MAXIMUM PEAK VOLTS (V)
PEAK AMPERES (A)
10
-2
10
-1
10
0
10
1
10
2
10
3
MAX CLAMPING VOLTAGE
MODEL SIZE 5mm
8 TO 68V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
10
V68ZA05
V56ZA05
V47ZA05
V39ZA05
V33ZA05
V27ZA05
V22ZA05
V18ZA05
V12ZA05
V8ZA05
10
-3
FIGURE 4. CLAMPING VOLTAGE FOR V82ZA05 - V330ZA05
2000
1000
500
200
MAXIMUM PEAK VOLTS (V)
PEAK AMPERES (A)
0.01 0.1 1 10 100 1000
100
0.0010.0001
V330ZA05
V270ZA05
V240ZA05
V220ZA05
V205ZA05
V180ZA05
V150ZA05
V120ZA05
V100ZA05
V82ZA05
MAX CLAMPING VOLTAGE
MODEL SIZE 5mm
82 TO 330V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
Transient V-I Characteristics Curves
2
VARISTOR
PRODUCTS
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ZA Varistor Series
Low to Medum Voltage, Radial Lead
Transient V-I Characteristics Curves (Continued)
FIGURE 5. CLAMPING VOLTAGE FOR V360ZA05 - V750ZA05 FIGURE 6. CLAMPING VOLTAGE FOR V8ZA1 - V68ZA2
FIGURE 7. CLAMPING VOLTAGE FOR V82ZA2 - V180ZA1 FIGURE 8. CLAMPING VOLTAGE FOR V8ZA2 - V68ZA3
FIGURE 9. CLAMPING VOLTAGE FOR V82ZA4 - V180ZA5 FIGURE 10. CLAMPING VOLTAGE FOR V18ZA3 - V68ZA10
3000
2000
1000
500
MAXIMUM PEAKVOLTS (V)
PEAK AMPERES (A)
0.01 0.1 1 10 100 10000.0010.0001
V750ZA05
V715ZA05
V680ZA05
V620ZA05
V470ZA05
V430ZA05
V390ZA05
V360ZA05
MAX CLAMPING VOLTAGE
MODEL SIZE 5mm
360 TO 750V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
500
400
300
200
100
90
80
70
60
50
40
30
20
10
MAXIMUM PEAKVOLTS (V)
10
-3
10
-2
10
-1
10
0
10
1
10
2
10
3
MAXIMUM CLAMPING VOLTAGE
8 TO 68V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
PEAK AMPERES (A)
V68ZA2
V56ZA2
V47ZA1
V39ZA1
V33ZA1
V27ZA1
V22ZA1
V12ZA1
V18ZA1
V8ZA1
MODEL SIZE 7mm
MAXIMUM PEAKVOLTS (V)
PEAK AMPERES (A)
10
-2
10
-1
10
0
10
1
10
2
10
3
10
-3
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 7mm
82 TO 180V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
4,000
3,000
2,000
1,000
900
800
700
600
500
400
300
200
100
10
4
V180ZA1
V150ZA1
V120ZA1
V100ZA3
V82ZA2
500
400
300
200
100
90
80
70
60
50
40
30
20
10
MAXIMUM PEAKVOLTS (V)
10
-3
10
-2
10
-1
10
0
10
1
10
2
10
3
PEAK AMPERES (A)
V68ZA3
V56ZA3
V47ZA3
V39ZA3
V33ZA2
V27ZA2
V22ZA2
V18ZA2
V8ZA2
V12ZA2
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 10mm
8 TO 68V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
MAXIMUM PEAKVOLTS (V)
PEAK AMPERES (A)
10
-2
10
-1
10
0
10
1
10
2
10
3
10
-3
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 10mm
82 TO 180V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
4,000
3,000
2,000
1,000
900
800
700
600
500
400
300
200
100
10
4
V180ZA5
V150ZA4
V120ZA4
V100ZA4
V82ZA4
600
500
400
300
200
100
90
80
70
60
50
40
30
20
10
-3
10
-2
10
-1
10
0
10
1
10
2
10
3
PEAK AMPERES (A)
MAXIMUM PEAKVOLTS (V)
V68ZA10
V56ZA8
V47ZA7
V39ZA6
V33ZA5
V27ZA4
V22ZA3
V18ZA3
MAXIMUM CLAMPING VOLTAGE
18 TO 68V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
MODEL SIZE 14mm
Varistor Products
84
www.littelfuse.com
Low to Medum Voltage, Radial Lead
ZA Varistor Series
Transient V-I Characteristics Curves (Continued)
FIGURE 11. CLAMPING VOLTAGE FOR V82ZA12 - V180ZA10 FIGURE 12. CLAMPING VOLTAGE FOR V18ZA40 - V36ZA80
FIGURE 13. CLAMPING VOLTAGE FOR V39ZA20 - V180ZA20
Transient V-I Characteristics Curves 
(Continued)
MAXIMUM PEAKVOLTS (V)
PEAK AMPERES (A)
10
-2
10
-1
10
0
10
1
10
2
10
3
10
-3
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 14mm
82 TO 180V
N(DC)
RATING
T
A
= -55
o
C TO 85
o
C
4,000
3,000
2,000
1,000
900
800
700
600
500
400
300
200
100
10
4
V180ZA10
V150ZA8
V120ZA6
V100ZA15
V82ZA12
300
200
100
90
80
70
60
50
40
30
20
MAXIMUM PEAKVOLTS (V)
PEAK AMPERES (A)
10
-2
10
-1
10
0
10
1
10
2
10
3
10
-3
10
4
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 20mm
18 TO 36V
N(DC)
RATING
T
A
=-55
o
CTO 85
o
C
V36ZA80
V33ZA70
V27ZA60
V24ZA50
V18ZA40
10
-3
10
-2
10
-1
10
0
10
1
10
2
10
4
10
3
1,000
500
300
200
30
PEAK AMPERES (A)
MAXIMUM PEAKVOLTS (V)
V56ZA20
V47ZA20
V39ZA20
MAXIMUM CLAMPING VOLTAGE
MODEL SIZE 20mm
T
A
= -55
o
C TO 85
o
C
39 TO 180V
M(AC)
RATING V180ZA20
V150ZA20
V120ZA20
100
50
V68ZA20
Pulse Rating Curves 
FIGURE 14. SURGE CURRENT RATING CURVES FOR V8ZA05 FIGURE 15. SURGE CURRENT RATING CURVES FOR 
V12ZA05 - V68ZA05
50
20
10
5
2
1
0.5
0.2
0.1
SURGE CURRENT (A)
20 100 1,000 10,000
IMPULSE DURATION (µs)
1
10
10
2
2
10
3
INDEFINITE
10
4
10
5
10
6
MODEL SIZE 5mm
V8ZA05
100
50
20
10
2
1
0.5
0.2
0.1
SURGE CURRENT (A)
20 100 1,000 10,000
IMPULSE DURATION ( µs)
INDEFINITE
10
4
10
5
10
6
MODEL SIZE 5mm
V12ZA05 - V68ZA05
110
10
2
2
10
3
2
VARISTOR
PRODUCTS
Varistor Products
85 www.littelfuse.com
ZA Varistor Series
Low to Medum Voltage, Radial Lead
Pulse Rating Curves (Continued)
FIGURE 16. SURGE CURRENT RATING CURVES FOR
V82ZA05 - V750ZA05
FIGURE 17. SURGE CURRENT RATING CURVES FOR
V8ZA1 - V12ZA1
FIGURE 18. SURGE CURRENT RATING CURVES FOR
V18ZA1 - V68ZA2
FIGURE 19. SURGE CURRENT RATING CURVES FOR
V82ZA2 - V180ZA1
FIGURE 20. SURGE CURRENT RATING CURVES FOR
V8ZA2 - V127ZA2
FIGURE 21. SURGE CURRENT RATING CURVES FOR
V18ZA2 - V68ZA3
50
20
10
5
2
1
0.5
0.2
SURGE CURRENT (A)
20 100 1,000 10,000
IMPULSE DURATION (µs)
1
10
10
2
210
3
INDEFINITE
10
4
10
5
10
6
MODEL SIZE 5mm
V82ZA05 - V750ZA05
500
200
100
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
10
10
2
2
10
3
INDEFINITE
10
4
10
5
10
6
200
100
50
20
10
5
2
1
0.5
0.2
MODEL SIZE 7mm
V8ZA1 - V12ZA1
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
10
10
2
2
10
3
INDEFINITE
500
200
100
50
20
10
2
1
0.5
0.2
10
4
10
5
10
6
5
MODEL SIZE 7mm
V18ZA1 - V68ZA2
2,000
1,000
200
100
50
20
10
5
1
2
500
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
2
10
10
2
10
4
10
5
10
6
10
3
INDEFINITE
MODEL SIZE 7mm
V82ZA2 - V180ZA1
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
10
10
2
2
10
3
INDEFINITE
500
200
100
50
20
10
2
1
0.5
0.2
10
4
10
5
10
6
5
MODEL SIZE 10mm
V8ZA2 - V12ZA2
1,000
500
100
50
20
10
5
1
2
200
20
SURGE CURRENT (A)
1
2
10
5
10
6
10
4
INDEFINITE
MODEL SIZE 10mm
V18ZA2 - V68ZA3
100 1,000 10,000
IMPULSE DURATION (µs)
10
2
10
3
Varistor Products
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Low to Medum Voltage, Radial Lead
ZA Varistor Series
Pulse Rating Curves (Continued)
FIGURE 22. SURGE CURRENT RATING CURVES FOR
V82ZA4 - V180ZA5
FIGURE 23. SURGE CURRENT RATING CURVES FOR
V18ZA3 - V68ZA10
FIGURE 24. SURGE CURRENT RATING CURVES FOR
V82ZA12 - V180ZA10
FIGURE 25. SURGE CURRENT RATING CURRENT FOR
V18ZA40 - V68ZA20
F
5,000
2,000
1,000
500
200
100
50
20
10
5
2
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
10
10
2
2
10
3
INDEFINITE
10
4
10
5
10
6
MODEL SIZE 10mm
V82ZA4 - V180ZA5
200
100
50
20
10
5
1
2
20 100 1,000 10,000
IMPULSE DURATION (µ
SURGE CURRENT (A)
1
2
10
10
2
INDEFINITE
1,000
500
5,000
2,000
200
100
50
20
10
5
2
500
20 100 1,000 10,000
IMPULSE DURATION (µs)
SURGE CURRENT (A)
1
2
10
10
4
10
5
10
6
10
3
INDEFINITE
1,000 10
2
MODEL SIZE 14mm
V82ZA12 - V180ZA10
2,000
200
100
50
20
10
5
2
500
20 100 1,000 10,000
IMPULSE DURATION (µ
SURGE CURRENT (A)
1
2
10
1,000
10
2
10
3
10
4
10
5
INDEFINITE
URGE CURRENT (A)
5,000
10,000
2,000
500
100
20
1
1,000
200
50
1
1
2
10
10
2
10
3
10
4
10
5
10
6
INDEFINITE
MODEL SIZE 20mm
V120ZA20 - V180ZA20
TRATING CURVES FOR
V 5
FIGURE 23. SURGE CURRENT RATING CURVES FOR
V18ZA3 - V68ZA10
F
1,000 10,000
I E DURATION ( µs)
10
4
10
5
10
6
MODEL SIZE 10mm
V82ZA4 - V180ZA5
200
100
50
20
10
5
1
2
20 100 1,000 10,000
IMPULSE DURATION ( µs)
SURGE CURRENT (A)
1
2
10
10
2
10
4
10
5
10
6
10
3
INDEFINITE
1,000
500
MODEL SIZE 14mm
V18ZA3 - V68ZA10
10
4
10
5
10
6
10
3
10
2
MODEL SIZE 14mm
V82ZA12 - V180ZA10
2,000
200
100
50
2
500
2
GE CURRENT (A)
1
2
10
1,000
10
2
10
3
10
4
10
5
10
6
MODEL SIZE 20mm
V18ZA40 - V68ZA20
1
2
VARISTOR
PRODUCTS
Varistor Products
87 www.littelfuse.com
ZA Varistor Series
Low to Medum Voltage, Radial Lead
NOTE: If pulse ratings are exceeded, a shift of VN(DC)(at specified current) of more then ±10% could result. This type of shift, which normally results in a decrease of VN(DC),
mayresult in the device not meeting the original published specifications, but does not prevent the device from continuing to function, and to provide ample protection.
Pulse Rating Curves (Continued)
FIGURE 24. SURGE CURRENT RATING CURVES FOR
V82ZA12 - V180ZA10
FIGURE 25. SURGE CURRENT RATING CURRENT FOR
V18ZA40 - V68ZA20
FIGURE 26. SURGE CURRENT RATING CURVES FOR V120ZA20 - V180ZA20
5,000
2,000
200
100
50
20
10
5
2
500
20 100 1,000 10,000
IMPULSE DURATION ( µs)
SURGE CURRENT (A)
1
2
10
10
4
10
5
10
6
10
3
INDEFINITE
1,000 10
2
MODEL SIZE 14mm
V82ZA12 - V180ZA10
2,000
200
100
50
20
10
5
2
500
20 100 1,000 10,000
IMPULSE DURATION ( µs)
SURGE CURRENT (A)
1
2
10
1,000
10
2
10
3
10
4
10
5
10
6
INDEFINITE
MODEL SIZE 20mm
V18ZA40 - V68ZA20
10,0001,000100
20
IMPULSE DURATION ( µs)
SURGE CURRENT (A)
5,000
10,000
2,000
500
100
20
10
2
1,000
200
50
1
5
1
2
10
10
2
10
3
10
4
10
5
10
6
INDEFINITE
MODEL SIZE 20mm
V120ZA20 - V180ZA20
Varistor Products
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ZA Varistor Series
Low to Medum Voltage, Radial Lead
Tape and Reel Specifications
5and 7mm Devices 10, 14 and 20mm Devices
2
VARISTOR
PRODUCTS
Varistor Products
89 www.littelfuse.com
Tape and Reel Data
•Conforms to ANSI and EIA specifications
•Can be supplied to IEC Publication 286-2
• Radial devices on tape are supplied with
crimped leads, straight leads, or under-
crimped leads
NOTE: Leads are offset by Dim e1
SYMBOL PARAMETER
MODEL SIZE
5mm 7mm 10mm 14mm 20mm
P Pitch of Component 12.7 ±1.0 12.7 ±1.0 25.4 ±1.0 25.4 ±1.0 25.4 ±1.0
P
0
Feed Hole Pitch 12.7 ±0.2 12.7 ±0.2 12.7 ±0.2 12.7 ±0.2 12.7 ±0.2
P
1
Feed Hole Center to Pitch 3.85 ±0.7 3.85 ±0.7 8.85 ±0.7 8.85 ± ±0.7 8.85 0.7
P
2
Hole Center to Component Center 6.35 ±1.0 6.35 ±1.0 12.7 ±0.7 12.7 ±0.7 12.7 ±0.7
FLead to Lead Distance 5.0 ±1.0 5.0 ±1.0 7.5 ±1.0 7.5 ±1.0 7.5 ±1.0
hComponent Alignment 2.0 Max 2.0 Max 2.0 Max 2.0 Max 2.0 Max
WTape Width 18.0 + 1.0
18.0 - 0.5
18.0 + 1.0
18.0 - 0.5
18.0 + 1.0
18.0 - 0.5
18.0 + 1.0
18.0 - 0.5
18.0 + 1.0
18.0 - 0.5
W
0
Hold Down Tape Width ±
12.0 0.3
±
12.0 0.3
±
12.0 0.3
±
12.0 0.3
±
12.0 0.3
W
1
Hole Position 9.0 + 0.75
9.0 - 0.50
9.0 + 0.75
9.0 - 0.50
9.0 + 0.75
9.0 - 0.50
9.0 + 0.75
9.0 - 0.50
9.0 + 0.75
9.0 - 0.50
W
2
Hold Down Tape Position 0.5 Max 0.5 Max 0.5 Max 0.5 Max 0.5 Max
HHeight from Tape Center to
Component Base
18.0 + 2.0
18.0 - 0.0
18.0 + 2.0
18.0 - 0.0
18.0 + 2.0
18.0 - 0.0
18.0 + 2.0
18.0 - 0.0
18.0 + 2.0
18.0 - 0.0
H
0
Seating Plane Height 16.0 ±0.5 16.0 ±0.5 16.0 ±0.5 16.0 ±0.5 16.0 ±0.5
H
1
Component Height 29.0 Max 32.0 Max 36.0 Max 40.0 Max 46.5 Max
D
0
Feed Hole Diameter 4.0 ±0.2 4.0 ±0.2 4.0 ±0.2 4.0 ±0.2 4.0 ±0.2
t Total Tape Thickness 0.7 ±0.2 0.7 ±0.2 0.7 ±0.2 0.7 ±0.2 0.7 ±0.2
U Under-crimp Width 8.0 Max
p Component Alignment 3
o
Max 3
o
Max 3
o
Max 3
o
Max 3
o
Max
NOTE: Dimensions are in mm.
8.0 Max 8.0 Max 8.0 Max 8.0 Max
Low to Medum Voltage, Radial Lead
ZA Varistor Series
Varistor Products
90
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Low to Medum Voltage, Radial Lead
ZA Varistor Series
Mechanical Dimensions
Tape and Reel Ordering Information
Crimped leads are standard on ZA types supplied in tape and reel and
are denoted by the model letter “T”. Model letter “S” denotes straight
leads and letter “U” denotes special under-crimped leads.
Example:
STANDARD 
MODEL
CRIMPED 
LEADS
STRAIGHT 
LEADS
UNDER-
CRIMPED 
LEADS
V18ZA3 V18ZT3 V18ZS3 V18ZU3
SHIPPING QUANTITY
SHIPPING QUANTITY
SIZE
RMS
(MAX)
VOLTAGE
QUANTITY PER REEL
“T”REEL “S” REEL “U” REEL
5mm All 1000 1000 1000
7mm All 1000 1000 1000
10mm All 500 500 500
14mm < 300V 500 500 500
14mm ≥300V 500 500 400
20mm < 300V 500 500 500
20mm ≥300V 500 500 400
SYM-
BOL
VOLTAGE
MODEL
VARISTOR MODEL SIZE
5mm 7mm 10mm 14mm 20mm
MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX
A All -
-
10
(0.394)
-
-
12
(0.472)
-
-
16
(0.630)
-
-
20
(0.787)
-
-
26.5
(1.043)
ø
D All -
-
7
(0.276)
-
-
9
(0.354)
-
-
12.5
(0.492)
-
-
17
(0.669)
-
-
23
(0.906)
e All 4
(0.157)
6
(0.236)
4
(0.157)
6
(0.236)
6.5
(0.256)
8.5
(0.335)
6.5
(0.256)
8.5
(0.335)
6.5
(0.256)
(Note 6)
8.5
(0.335)
(Note 6)
e
1
V8ZA-
V56ZA
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
V68ZA-
V100ZA
1.5
(0.059)
3.5
(0.138)
1.5
(0.059)
3.5
(0.138)
1.5
(0.059)
3.5
(0.138)
1.5
(0.059)
3.5
(0.138) (0.059) (0.138)
1.5 3.5
V120ZA-
V180ZA
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
1
(0.039)
3
(0.118)
1
(0.038)
3
(0.118) (0.038) (0.118)
V205ZA-
V750ZA
1.5
(0.059)
3.5
(0.138)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
E V8ZA-
V56ZA
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
V68ZA-
V100ZA
-
-
5.6
(0.220)
-
-
5.6
(0.220)
-
-
5.6
(0.220)
-
-
5.6
(0.220)
-
-
5.6
(0.220)
V120ZA-
V180ZA
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
-
-
5
(0.197)
V205ZA-
V750ZA
-
-
5.6
(0.220)
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
ø
b All 0.585
(0.023)
0.685
(0.027)
0.585
(0.023)
0.685
(0.027)
0.76
(0.030)
0.86
(0.034)
0.76
(0.030)
0.86
(0.034)
0.76
(0.030)
0.86
(0.034)
NOTES: Dimensions in millimeters, inches in parentheses.
6. 10mm ALSO AVAILABLE; See Additional Lead Style Options.
7. V24ZA50 and V24ZC50 only supplied with lead spacing of 6.35mm ±0.5mm (0.25 ±0.0196)
Dimension E = 5.85 min. Does not apply to T&R parts.
13
2
VARISTOR
PRODUCTS
Varistor Products
91 www.littelfuse.com
ZA Varistor Series
Low to Medum Voltage, Radial Lead
Additional Lead Style Options
Radial lead types can be supplied with combination preformed crimp and
trimmed leads. This option is supplied to the dimensions shown.
•To order this crimped and trimmed lead style, standard radial type
model numbers are changed by replacing the model letter “ZA” with
“ZC”. This option is supplied in bulk only.
Example:
For crimped leads without trimming and any varitions to the above,
contact Littelfuse.
•For 10/±1mm lead spacing on 20mm diameter models only; append stan-
dard model numbers by adding “X10”.
Example:
*SEATING PLANE INTERPRETATION PER IEC-717
CRIMPED AND TRIMMED LEAD
STANDARD CATALOG
MODEL ORDER AS:
V18ZA3 V18ZC3
VARISTOR
VARISTOR NOMINAL
VOLTAGE (V
NOM
)
(One, Two or Three Digits)
SERIES DESIGNATOR/
LEAD STYLE DESIGNATOR
ZC= Crimped and Clipped
ZS= Straight
ZT = Crimped
ZU= Under Crimped
V XXX ZA XX
RELATIVE ENERGY INDICATOR
(One or Two Digits)
Ordering Information
ZA series Varistors are shipped standard in bulk pack with straight leads
and lead spacing outlined in the package dimensions on page 4-13.
Contact your Littelfuse sales representative to discuss the non-standard
options outlined below.
ZA series varistors for Hi-Temperature operating conditions:
•Phenolic Coated ZA Series devices are available with improved maxi-
mum operating maximum temperature 125°C.
•These devices also have improved temperature cycling performance
capability.
•Ratings and Specifications are as per standard ZA Series except Hi-
Pot encapsulation Isolation Voltage Capability = 500V.
•To order: add X1347 to part number (e.g. V22ZA3X1347)
•Marked identifier will contain 'P' to denote Phenolic.
•These devices are not UL, CSA, VDE or CECC certified.
•Contact factory for further details.
SYMBOL
VARISTOR MODEL SIZE
5mm 7mm 10mm 14mm 20mm
MIN MAX MIN MAX MIN MAX MIN MAX MIN MAX
A-
-
13.0 
(0.512)
-
-
15
(0.591)
-
-
19.5 
(0.768)
-
-
22.5 
(0.886)
-
-
29.0 
(1.142)
L
TRIM
2.41 
(0.095)
4.69 
(0.185)
2.41 
(0.095)
4.69 
(0.185)
2.41 
(0.095)
4.69 
(0.185)
2.41 
(0.095)
4.69 
(0.185)
2.41 
(0.095)
4.69 
(0.185)
NOTE: Dimensions in millimeters, inches in parentheses.
STANDARD CATALOG
MODEL ORDER AS:
V18ZA40 V18ZA40X10