Varistors (ZNR Surge Absorber)
E type
Varistors (ZNR Surge Absorber) Type E is capable of handling larger surge
energy than Type D in applications to protect electronic equipment or
semiconductor devices from switching and induced lightning surges.
Features
●UL and CSA recognized components
●Very large surge withstanding capability with a compact size
●Direct mounting on boards like a power distribution board available
●Fast response to steep impulse voltage
●Low clamping voltage for better surge protection
●RoHS compliant
Recommended applications
●Transistor, diode, IC, thyristor or triac semiconductor protection
●Surge protection in industrial power plant operations
●Relay or electromagnetic valve surge absorption
●Surge absorption applications in broadcasting, communications devices, traffic/railroad,
agricultural facilities, waterworks
●Surge protection of automatic control devices for power distribution line
Related standards
Standard No.
Title
UL1449
Surge protective devices
CSA C22.2 No.269.5
Surge protective devices - Type 5 – Components
●Each type designation is not registered by Part Number.
Note : Ask our factory for Product Specification before use.
■ As for handling precautions and minimum quantity / Packing unit please see related information.
Explanation of part numbers
1
2
3
4
Ｅ
Ｒ
Ｚ
Ｃ
Product code
5
6
7
8
E
Ｋ
Type
Tolerance
Element size
9
10
11
Nominal varistor voltage
12
Design No.
―
General
Y
UL/CSA Recognized
Dimensions in mm (not to scale)
ISO
M4
4.3
24
Unit : mm
L
W
W
H
L
ERZC20EK□□□(Y)
48±1
42±1
39±1
ERZC32EK□□□(Y)
60±1
55±1
51±1
5
12
Part No.
H
ZNR
Part No.
Date code
14
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
14-Dec-20
E type / 20, 32 series (UL and CSA Recognized)
Ratings and characteristics (20 series)
●Operating temperature range : ‒40 to 85 ℃
Part No.
（UL/CSA
Recognized）
Type
designation
Varistor
voltage
at 1 mA
●Storage temperature range : ‒40 to 110 ℃
Maximum
allowable
voltage
Maximum
peak
current
Maximum
clamping
voltage
at 100 A
Maximum
energy
1 time
1 time
(2ms)
(8/20μs)
Rated
voltage
(UL/CSA)
(Ｖ)
Acrms
(Ｖ)
DC
(Ｖ)
(V)
(J)
（A）
ACrms (Ｖ)
200 (185 to 225)
130
170
340
80
8000
118
ERZC20EK201Y
20EK201U
ERZC20EK241Y
20EK241U
240 (216 to 264)
150
200
395
95
8000
136
ERZC20EK271Y
20EK271U
270 (247 to 303)
175
225
455
100
8000
159
ERZC20EK361Y
20EK361U
360 (324 to 396)
230
300
595
120
8000
209
ERZC20EK391Y
20EK391U
390 (351 to 429)
250
320
650
130
8000
227
ERZC20EK431Y
20EK431U
430 (387 to 473)
275
350
710
140
8000
250
ERZC20EK471Y
20EK471U
470 (423 to 517)
300
385
775
150
8000
272
ERZC20EK511Y
20EK511U
510 (459 to 561)
320
415
845
150
8000
291
ERZC20EK621Y
20EK621U
620 (558 to 682)
385
505
1025
160
8000
350
ERZC20EK681Y
20EK681U
680 (612 to 748)
420
560
1120
175
8000
381
ERZC20EK751Y
20EK751U
750 (675 to 825)
460
615
1240
190
8000
418
ERZC20EK781Y
20EK781U
780 (702 to 858)
485
640
1290
200
8000
440
ERZC20EK821Y
20EK821U
820 (738 to 902)
510
670
1355
215
8000
463
ERZC20EK911Y
20EK911U
910 (819 to 1001)
550
745
1500
240
8000
500
ERZC20EK102Y
20EK102U
1000 (900 to 1100)
625
825
1650
245
8000
568
ERZC20EK112Y
20EK112U
1100 (990 to 1210)
680
895
1815
250
8000
600
Ratings and characteristics (32 series)
●Operating temperature range : ‒40 to 85 ℃
Part No.
（UL/CSA
Recognized）
Type
designation
Varistor
voltage
at 1 mA
●Storage temperature range : ‒40 to 110 ℃
Maximum
allowable
voltage
Maximum
peak
current
Maximum
clamping
voltage
at 200 A
Maximum
energy
1 time
1 time
(2ms)
(8/20μs)
Rated
voltage
(UL/CSA)
(Ｖ)
Acrms
(Ｖ)
DC
(Ｖ)
(V)
(J)
（A）
ACrms (Ｖ)
ERZC32EK201Y
32EK201U
200 (185 to 225)
130
170
340
210
25000
118
ERZC32EK241Y
32EK241U
240 (216 to 264)
150
200
395
240
25000
136
ERZC32EK271Y
32EK271U
270 (247 to 303)
175
225
455
255
25000
159
ERZC32EK361Y
32EK361U
360 (324 to 396)
230
300
595
325
25000
209
ERZC32EK391Y
32EK391U
390 (351 to 429)
250
320
650
350
25000
227
ERZC32EK431Y
32EK431U
430 (387 to 473)
275
350
710
400
25000
250
ERZC32EK471Y
32EK471U
470 (423 to 517)
300
385
775
405
25000
272
ERZC32EK511Y
32EK511U
510 (459 to 561)
320
415
845
405
25000
291
ERZC32EK621Y
32EK621U
620 (558 to 682)
385
505
1025
415
25000
350
ERZC32EK681Y
32EK681U
680 (612 to 748)
420
560
1120
450
25000
381
ERZC32EK751Y
32EK751U
750 (675 to 825)
460
615
1240
500
25000
418
ERZC32EK781Y
32EK781U
780 (702 to 858)
485
640
1290
520
25000
440
ERZC32EK821Y
32EK821U
820 (738 to 902)
510
670
1355
545
25000
463
ERZC32EK911Y
32EK911U
910 (819 to 1001)
550
745
1500
600
25000
500
ERZC32EK102Y
32EK102U
1000 (900 to 1100)
625
825
1650
620
25000
568
ERZC32EK112Y
32EK112U
1100 (990 to 1210)
680
895
1815
640
25000
600
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
14-Dec-20
E type / 20, 32 series
Ratings and characteristics (20 series)
●Storage temperature range : ‒40 to 110 ℃
●Operating temperature range : ‒40 to 85 ℃
Part No.
Varistor
voltage
at 1 mA
Maximum
allowable
voltage
Maximum
clamping
voltage
at 100 A
Rated
power
Maximum
energy
(2ms)
Maximum
peak current
(8/20 μs)
1 time
2 times
Typical
capacitance
(Reference)
at 1 kHz
(Ｖ)
Acrms
(Ｖ)
DC
(Ｖ)
(V)
(W)
(J)
（A）
（A）
(pF)
ERZC20EK201
200 (185 to 225)
130
170
340
0.8
80
8000
5000
2300
ERZC20EK241
240 (216 to 264)
150
200
395
0.8
95
8000
5000
1500
ERZC20EK271
270 (247 to 303)
175
225
455
0.8
100
8000
5000
1400
ERZC20EK361
360 (324 to 396)
230
300
595
0.8
120
8000
5000
1300
ERZC20EK391
390 (351 to 429)
250
320
650
0.8
130
8000
5000
1200
ERZC20EK431
430 (387 to 473)
275
350
710
0.8
140
8000
5000
1000
ERZC20EK471
470 (423 to 517)
300
385
775
0.8
150
8000
5000
950
ERZC20EK511
510 (459 to 561)
320
415
845
0.8
150
8000
5000
930
ERZC20EK621
620 (558 to 682)
385
505
1025
0.8
160
8000
5000
900
ERZC20EK681
680 (612 to 748)
420
560
1120
0.8
175
8000
5000
850
ERZC20EK751
750 (675 to 825)
460
615
1240
0.8
190
8000
5000
800
ERZC20EK781
780 (702 to 858)
485
640
1290
0.8
200
8000
5000
800
ERZC20EK821
820 (738 to 902)
510
670
1355
0.8
215
8000
5000
700
ERZC20EK911
910 (819 to 1001)
550
745
1500
0.8
240
8000
5000
700
ERZC20EK102
1000 (900 to 1100)
625
825
1650
0.8
245
8000
5000
400
ERZC20EK112
1100 (990 to 1210)
680
895
1815
0.8
250
8000
5000
350
Ratings and characteristics (32 series)
●Operating temperature range : ‒40 to 85 ℃
Part No.
Varistor
voltage
at 1 mA
●Storage temperature range : ‒40 to 110 ℃
Maximum
allowable
voltage
Maximum
clamping
voltage
at 200 A
Rated
power
Maximum
energy
(2ms)
Maximum
peak current
(8/20 μs)
1 time
2 times
Typical
capacitance
(Reference)
at 1 kHz
(Ｖ)
Acrms
(Ｖ)
DC
(Ｖ)
(V)
(W)
(J)
（A）
（A）
(pF)
200 (185 to 225)
130
170
340
1.2
210
25000
20000
5500
ERZC32EK241
240 (216 to 264)
150
200
395
1.2
240
25000
20000
5000
ERZC32EK271
270 (247 to 303)
175
225
455
1.2
255
25000
20000
4200
ERZC32EK361
360 (324 to 396)
230
300
595
1.2
325
25000
20000
3500
ERZC32EK391
390 (351 to 429)
250
320
650
1.2
350
25000
20000
3000
ERZC32EK431
430 (387 to 473)
275
350
710
1.2
400
25000
20000
2500
ERZC32EK471
470 (423 to 517)
300
385
775
1.2
405
25000
20000
2500
ERZC32EK511
510 (459 to 561)
320
415
845
1.2
405
25000
20000
2400
ERZC32EK621
620 (558 to 682)
385
505
1025
1.2
415
25000
20000
2200
ERZC32EK681
680 (612 to 748)
420
560
1120
1.2
450
25000
20000
2100
ERZC32EK751
750 (675 to 825)
460
615
1240
1.2
500
25000
20000
2000
ERZC32EK201
ERZC32EK781
780 (702 to 858)
485
640
1290
1.2
520
25000
20000
1900
ERZC32EK821
820 (738 to 902)
510
670
1355
1.2
545
25000
20000
1800
ERZC32EK911
910 (819 to 1001)
550
745
1500
1.2
600
25000
20000
1700
ERZC32EK102
1000 (900 to 1100)
625
825
1650
1.2
620
25000
20000
1000
ERZC32EK112
1100 (990 to 1210)
680
895
1815
1.2
640
25000
20000
800
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
14-Dec-20
E type / 20 series
Typical characteristics
Voltage vs. Current
(ERZC20EK201(Y) to ERZC20EK511(Y))
Max.Leakage
Current
2000
Max.Clamping Voltage
ERZC20EK511(Y)
ERZC20EK471(Y)
ERZC20EK391(Y)
ERZC20EK361(Y)
Voltage (V)
1000
900
800
700
600
500
ERZC20EK271(Y)
ERZC20EK241(Y)
ERZC20EK201(Y)
400
300
200
100
90
80
70
60
50
Test current waveform
10–6 to 10–3 A: Direct current
10–1 to 104 A: 8/20 μs
40
30
10-6
10-5
10-4
10-3
10-2
10-1
100
Current (A)
101
102
103
104
105
(ERZC20EK621(Y) to ERZC20EK112(Y))
Max.Leakage
Current
4000
Max.Clamping Voltage
ERZC20EK112(Y)
ERZC20EK102(Y)
ERZC20EK911(Y)
ERZC20EK821(Y)
ERZC20EK781(Y)
ERZC20EK751(Y)
ERZC20EK681(Y)
ERZC20EK621(Y)
3000
Voltage (V)
2000
1000
900
800
700
600
500
400
Test current waveform
10–6 to 10–3 A: Direct current
10–1 to 104 A: 8/20 μs
300
200
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
Current (A)
Impulse derating curve (Relation be tween impulse width and surge, repetitively)
(ERZC20EK201(Y) to ERZC20EK271(Y))
2 times：5 min. interval
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
10000
8000
6000
4000
(ERZC20EK361(Y) to ERZC20EK681(Y))
10000
8000
6000
4000
2 times：5 min. interval
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
2000
2000
1000
800
600
1000
800
600
400
1000
800
600
400
400
200
100
80
60
40
Impulse Current（A)
2000
Impulse Current（A)
Impulse Current（A)
10000
8000
6000
4000
200
100
80
60
40
100
80
60
40
20
20
10
8
6
4
10
8
6
4
10
8
6
4
2
2
2
1
100
1000
Impulse Width（μs）
10000
20
100
1000
10000
2 times：5 min. interval
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
200
20
1
20
(ERZC20EK751(Y) to ERZC20EK112(Y))
1
20
Impulse Width（μs）
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
100
1000
10000
Impulse Width（μs）
14-Dec-20
E type / 32 series
Typical characteristics
Voltage vs. Current
(ERZC32EK201(Y) to ERZC32EK511(Y))
Max.Leakage
Current
2000
Max.Clamping Voltage
ERZC32EK511(Y)
ERZC32EK471(Y)
ERZC32EK431(Y)
ERZC32EK391(Y)
ERZC32EK361(Y)
1000
900
800
700
600
ERZC32EK271(Y)
ERZC32EK241(Y)
ERZC32EK201(Y)
500
Voltage (V)
400
300
200
100
90
80
70
60
Test current waveform
10–6 to 10–3 A: Direct current
10–1 to 104 A: 8/20 μs
50
40
30
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
Current (A)
(ERZC32EK621(Y) to ERZC32EK112(Y))
Max.Leakage
Current
2000
Max.Clamping Voltage
ERZC32EK511(Y)
ERZC32EK471(Y)
ERZC32EK431(Y)
ERZC32EK391(Y)
ERZC32EK361(Y)
1000
900
800
700
600
ERZC32EK271(Y)
ERZC32EK241(Y)
ERZC32EK201(Y)
500
Voltage (V)
400
300
200
100
90
80
70
60
Test current waveform
10–6 to 10–3 A: Direct current
10–1 to 104 A: 8/20 μs
50
40
30
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
Current (A)
Impulse derating curve (Relation be tween impulse width and surge, repetitively)
(ERZC32EK201(Y) to ERZC32EK271(Y))
20000
20000
2 times：5 min. interval
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
10000
8000
6000
(ERZC32EK751(Y) to ERZC32EK112(Y))
2 times：5 min. interval
20000
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
10000
8000
6000
4000
2000
2000
2000
1000
800
600
1000
800
600
1000
800
600
200
100
80
60
40
4000
Impulse Current（A)
400
400
200
100
80
60
40
400
200
100
80
60
40
20
20
20
10
8
6
4
10
8
6
4
10
8
6
4
2
20
100
1000
Impulse Width（μs）
10000
2
2 times：5 min. interval
up to 10 times：2 min. interval
up to 106 times : 10 sec. interval
10000
8000
6000
4000
Impulse Current（A)
Impulse Current（A)
(ERZC32EK361(Y) to ERZC32EK681(Y))
20
100
1000
10000
2
20
Impulse Width（μs）
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
100
1000
10000
Impulse Width（μs）
14-Dec-20
E type
Performance characteristics
Characteristics
Test methods / Description
Specifications
Electrical measurements (initial/after tests) shall be conducted at temperature of 5 to 35
℃, relative humidity of maximum 85 %.
The voltage betwen two terminals with the specified measuring current CmA DC applied
is called VC or VCmA. The measurement shall be made as fast as possible to avoid heat
affection.
The maximum sinusoidal wave voltage (rms) or the maximum DC
voltage that can be applied continuously.
The maximum voltage between two terminals with the specified
standard impulse current (8/20 μs).
Standard test
condition
Varistor voltage
Maximum
allowable voltage
Clamping voltage
Rated power
The maximum power that can be applied within the specified ambient temperature.
The maximum energy within the varistor voltage change of ±10 % when one impulse of 2
ms is applied.
The maximum current within the varistor voltage change of ±10 %
２times with the standard impulse current (8/20 μs) applied two times with an interval of 5
Maximum
minutes.
peak current
The maximum current within the varistor voltage change of ±10 %
１time
with the standard impulse current (8/20 μs) applied one time.
Temperature
Vc at 70 ℃ - Vc at 20 ℃
1
× 100(%/℃)
coefficient of varistor
×
50
Vc
at
20
℃
voltage
―
To meet the
specified value
Electrical
Maximum energy
The change of VC shall be measured after the impulse current listed below is applied
10000 times continuously with the interval of 10 seconds at room temperature.
Mechanical
Impulse life
Withstanding voltage
(Body insulation)
Robustness of
terminations
(Tensile)
Vibration
200 A (8/20 μs)
Series 32
300 A (8/20 μs)
The commercial frequency voltage of AC 2.5 kV shall be applied between terminals and
the bottom of the unit for one minute.
After gradually applying the load of 49 N (5 kgf) and keeping the
unit fixed for 10 seconds in an axial direction, the terminal shall be visually examined for
any damage.
After repeadly applying a single harmonic vibration (amplitude:
0.75 mm): double amplitude: 1.5 mm with 1 minute vibration frequency cycles (10 Hz to
55 Hz to 10 Hz) to each of three
perpendicular directions for 2 hours. Thereafter, the damage of the
terminals is visually examined.
The specimen shall be subjected to 110±3 ℃ for 500 hours
in a thermostatic bath without load and then stored at room
temperature and humidity for one to two hours. Thereafter, the change of Vc shall be
measured.
Dry heat/ High
temperature
storage
Environmental
Series 20
Step
Temperature (℃）
1
-25
2
0
-3
Period (minutes)
30
Room Temp.
3
85
4
+3
..0
Room temp.
0 to ‒0.05 %/ ℃ max.
ΔV1 mA/V1 mA ≦±10%
No remarkable damage
ΔV1 mA/V1 mA ≦ ±5 %
+3
..0
3 max.
30
+3
..0
3 max.
The temperature cycle shown below shall be repeated five times and then stored at room
temperature and humidity for one to two hours. The change of Vc and mechanical
damage shall be examined.
After being continuously applied the Maximum Allowable Voltage
Dry heat load/
at 85±5 ℃ for 500 hours, the specimen shall be stored at room
High temperature
temperature and humidity for one to two hours. Thereafter, the change of Vc shall be
load
measured.
The specimen shall be subjected to 40±2 ℃, 90 to 95 %RH for 1000 hours without load
Damp heat/Humidity
and then stored at room temperature and humidity for one to two hours. Thereafter, the
(Steady state)
change of Vc shall be measured.
Temperature cycle
ΔV1 mA/V 1mA ≦ ±5 %
ΔV1 mA/V1 mA ≦ ±10 %
ΔV1 mA/V1 mA ≦ ±5 %
Minimum quantity / Packing unit
Product
“ZNR”
Transient/surge
absorbers
Part number
Minimum quantity
/ Packing unit
Packing quantity
in carton
General product
ERZC□□EK□□□
5
100
UL and CSA recognized
ERZC□□EK□□□Y
5
100
Series / Type
E type
Carton (about)
L×W×H (mm)
380×405×85
380×405×85
Part No., quantity and country of origin are designated on outer packages in English.
※ Please contact local sales office about packing specifications.
Design and specifications are each subject to change without notice. Ask factory for the current technical specifications before purchase and/or use.
Should a safety concern arise regarding this product, please be sure to contact us immediately.
14-Dec-20
Guidelines and precautions regarding the
technical information and use of our products
described in this online catalog.
■ If you want to use our products described in this online catalog for applications requiring special
qualities or reliability, or for applications where the failure or malfunction of the products may directly
jeopardize human life or potentially cause personal injury (e.g. aircraft and aerospace equipment,
traffic and transportation equipment, combustion equipment, medical equipment, accident prevention,
anti-crime equipment, and/or safety equipment), it is necessary to verify whether the specifications of
our products fit to such applications. Please ensure that you will ask and check with our inquiry desk
as to whether the specifications of our products fit to such applications use before you use our products.
■ The quality and performance of our products as described in this online catalog only apply to our
products when used in isolation. Therefore, please ensure you evaluate and verify our products under
the specific circumstances in which our products are assembled in your own products and in which our
products will actually be used.
■ If you use our products in equipment that requires a high degree of reliability, regardless of the
application, it is recommended that you set up protection circuits and redundancy circuits in order
to ensure safety of your equipment.
■ The products and product specifications described in this online catalog are subject to change for
improvement without prior notice. Therefore, please be sure to request and confirm the latest product
specifications which explain the specifications of our products in detail, before you finalize the design
of your applications, purchase, or use our products.
■ The technical information in this online catalog provides examples of our products' typical operations
and application circuits. We do not guarantee the non-infringement of third party's intellectual property
rights and we do not grant any license, right, or interest in our intellectual property.
■ If any of our products, product specifications and/or technical information in this online catalog is to
be exported or provided to non-residents, the laws and regulations of the exporting country,
especially with regard to security and export control, shall be observed.
■ The switchover date for compliance with the RoHS Directive/REACH Regulations varies depending
on the part number or series of our products.
■ When you use the inventory of our products for which it is unclear whether those products are
compliant with the RoHS Directive/REACH Regulation, please select "Sales Inquiry" in the website
inquiry form and contact us.
We do not take any responsibility for the use of our products outside the scope of the
specifications, descriptions, guidelines and precautions described in this online catalog.
16-Apr-21
c
Varistors (ZNR Surge Absorber)
Handling Precautions (E, CK,SC type)
1. Safety precautions
In case that a Varistors (ZNR Surge Absorber) (hereafter referred to as the ZNR, or product name) is used,
if an abnormality takes place because of peripheral conditions of the ZNR(material, environments, power
source conditions, circuit conditions, etc. in equipment design), fire, electric shock, burn, or product failure
may be occur. The precautions for this product are described below, understand the content thoroughly
before usage. For more questions, contact us.
If there's any uncertainty/doubt/products safety items, please contact us. When a dogma shall be occurred
about safety for this products, be sure to inform us rapidly, operate your technical examination.
2. Precautions to be strictly observed
2.1 Confirmation of performance ratings
Use the ZNR within its rated range of performance such as the Max. allowable voltage, withstanding surge
current, withstanding energy, impulse life(surge life), average pulse power, and operating temperature range.
If used outside the range, the ZNR can be degrade and have element fracture, which may result in smoking
and ignition.
2.2 To avoid accidents due to unexpected phenomena, take the following measures
・ Across-the-line use
When the ZNR is used across a line, put a current fuse in series with the ZNR (Refer to Table 1).
・ Use between line to ground
(1) If the case that the ZNR is used between a line to the ground, the short-circuit of the ZNR may not
blow the current fuse because of grounding resistance, which may cause smoking and ignition of the
ZNR’s exterior resin.
As the measure against it, install an earth leakage breaker on the power supply side of the ZNR
position. If no earth leakage breaker is installed, use a thermal fuse together wth a current fuse in
series. (Refer to Table 1.)
(2) If the case that the ZNR is used between a live part to metal case, an electric shock may develop at a
short shortcircuit of the ZNR ; hence, ground the metal case to the ground or keep it from the human body.
・ In the event of fracture of the ZNR, its pieces may scatter ; hence, put the case or cover of the set product
in place.
・ Do not install the ZNR near combustible substances(polyvinyl chloride wires, resin moldings, etc.).
If it is difficult to do, install a nonflammable cover.
2.3 The live part shall be equipped with a protective cover for preventing electric shock.
2.4 If ZNR is shorted out and happen smoke or ignition, please cut provided current to ZNR immediately.
3. Application notes
3.1 Pay attention to the following items to avoid the shortened life and failure of the ZNR
3.1-1 Circuit conditions
(1) Select a ZNR of which the maximum voltage including fluctuations in source voltage allows for the
(2) In cases that surges are intermittently applied at short intervals (for example, in the case that the voltage
of the noise simulator test is impressed), do not cause them to exceed the ZNR's rated pulse power.
(3) Select a ZNR recommended in Table 1.
① Across-the-Line Use
Because the primary line voltage temporarily rises due to load unbalance of separately wired loads, short
circuit between the live line and the neutral line or LC resonance at switching for a capacitate load, ZNR
with * are recommended for AC100V or AC120V applications.
② Line to ground Use
・ When DC500V insulation resistance test of the circuits employing ZNR is conducted, the ZNR shall be
removed after getting approval from the customer, or the ZNR ** with the Maximum Allowable voltage
exceeding to the test voltage shall be applied.
・ When AC1000V dielectric with standing test is conducted, ZNR shall be removed after getting approval
from the customer according to the relevant regulations, or the ZNR *** with the Maximum Allowable
voltage exceeding to the test voltage shall be applied.
● Recommendation fuse
Series
Current fuse
(Line - Line)
Thermal. fuse
(Line - Ground )
ERZC20EK□□□(□)
ERZC32EK□□□(□)
ERZVS34C□□□
ERZC□□CK□□□W
10 A max.
20 A max.
20 A max.
20 A max.
100 to 120 ℃ 5 A
100 to 120 ℃ 10 A
100 to 120 ℃ 10 A
100 to 120 ℃ 10 A
◆ Fuses shall use rated voltages ap pro pri ate for circuits.
◆ Finally, confi rm that the secondary disaster does not occur even if the ZNR mounted on equipment breaks.
◆ Set a thermal fuse to get high thermal conductivity with ZNR.
14-Dec-20
c
Varistors (ZNR Surge Absorber)
The recommended fuse position is shown in Table.1, "Example of ZNR application", however, if the
load current of protected equipment is larger than that of the above recommended fuse rated current,
install a current fuse at the position shown below.
Current fuse
Protected
equipment
Power source side
ZNR
Table 1 Example of ZNR application
Across-the-Line use
Use between Line to ground
DC/AC
Single-phase
DC/AC
Single-phase
fuse
fuse
ZNR1
ZNR1
Protected
Equipment
Protected
Equipment
Connections example
ZNR2
Thermal coupling
AC 3-phase
Thermal fuse
AC 3-phase
fuse
fuse
ZNR3
ZNR3
Protected
Equipment
Protected
Equipment
ZNR4
Thermal coupling
Selection Examples
ZNR
Nominal
line voltage
[AC]
Part Number of ZNR
E, CK, SC type
201
241
271
100 V
120 V
ZNR 1
ZNR 3
200 V
to 220 V
ZNR
ERZC□□EK
ERZC□□CK
ERZVS34C
241
271*
Nominal
line voltage
[AC]
E, CK, SC type
471
511
821 and more **
ERZC□□EK
ERZC□□CK
ERZVS34C
ZNR 2
ZNR 4
471
511
Part Number of ZNR
100 V
to 220 V
240 V
240 V
Thermal fuse
Regarding the part
applying to AC
withstanding
voltage test, please
ask us.
511
821 and more **
Regarding the part
applying to AC
withstanding
voltage test, please
ask us.
14-Dec-20
c
Varistors (ZNR Surge Absorber)
3.1-2 Operating environments
(1) The ZNR is designed and manufactured for application in general purpose electronic devices.
The ZNR shall not be exposed to the weather, except for usage inside unit.
(2) Do not use the ZNR in places exposed to temperatures beyond the operating temperature range, such as places
exposed to sunlight and vicinities of heating equipment.
(3) Do not use the ZNR in places exposed to high temperatures and high humidity, such as places exposed directly
to rain, wind, dew condensation, and vapor.
(4) Do not use the ZNR in dusty and salinity environment and atmospheres polluted by corrosive gases, in liquids
such as water, oil, chemical, organic solvent.
3.1-3 Processing conditions
(1) Do not wash the ZNR by such solvents(thinner, acetone, etc.) as its exterior resin deteriorates.
(2) Do not apply a strong vibration or shock (by falling, etc.) to the ZNR, cracking to its exterior resin and element
may occur. and element may occur.
(3) When coating the ZNR with resin(including molding), do not use such resin.
(4) Do not bend the ZNR lead wires at the position close to its ZNR exterior resin, or apply external force to the
position.
(5) When soldering the ZNR lead wires, follow the recommended condition and do not melt the solder and insulating
materials constituting the ZNR.
(6) Keep the wiring of the ZNR as short and straight as possible.
3.1-4 Long-term storage
(1) Do not store the ZNR under high temperature and high humidity. Store it indoor environment at a temperature
up to 40 ℃ and at humidity below 75 %RH, and use it within two years.
Before using the ZNR that has been stored for a long period(two years or longer), confirm the solderability.
(2) Avoid atmospheres full of corrosive gases (hydrogen sulfide, sulfurous acid, chlorine, ammonia, etc.).
(3) Avoid direct sunlight and dew condensation.
4. Notices
・ In cases that the ZNR is used in equipment (aerospace equipment, medical equipment, etc.) requiring extremely
high reliability, ask us for selection of part No., and protection coordination, etc. in advance.
・ There is possibility that the ZNR will unexpectedly smoke or ignite because of abnormal rise of the circuit voltage
and invasion of excessive surge.
・ To prevent that accident from spreading over the equipment and not to expand the damage, use multiplex protection
such as the adoption of frame-retardant materials for housing parts and structural parts.
・ We don’t bear any responsibility for product malfunction or abnormal conditions which caused by using beyond
the descriptions in this product specification.
・ Package marking includes the product number, quantity, and country of origin. As a rule, country of origin should
be indicated in English.
5. Applicable laws and regulations , others
・ This product not been manufactured with any ozone depleting chemical controlled under the Montreal Protocol.
・ Specified brominated flame retardants (including PBB (polybromobiphenyl) and PBDE (polybromodiphenyl
ether)) are not intentionally used in the components of this product.
・ This product comply with RoHS(Restriction of the use of certain Hazardous Substance in electrical and electronic
equipment) (DIRECTIVE 2011/65/EU and 2015/863/EU).
・ All the materials used in this part are registered material under the Law Concerning the Examination and
Regulation of Manufacture, etc. of Chemical Substance.
・ If you need the notice by letter of “A preliminary judgement on the Laws of Japan foreign exchange and Foreign
Trade Control”, be sure to let us know.
・ These products are not dangerous goods on the transportation as identified by UN(United nations) numbers
or UN classification.
6. Others
・ As to the disposal of ZNR, check the method of disposal in each country or origin where the ZNR are incorporated
in your products to be used.
・ The technical information in this specification provides example of our products’ typical operations and application
circuit. We do not guarantee the non-infringement of third party’s intellectual property rights and we do not grant
any license, right or interest in our intellectual property.
14-Dec-20
工商网监
湘ICP备2023018690号
