Silicon Carbide Varistors - Zinc Oxide MOV’s

SiC Disk Varistors | SiC Rod and Tube Varistors | MOV / Zinc Oxide (ZnO) Varistor  | Silicon Carbide Varistors with Leads | Si-Metal Ceramic Composite Resistors | ZnO Block Varistors

About Silicon Carbide Varistors Our Silicon carbide varistors are made from about 90% silicon carbide of different grain sizes and 10% ceramic binder and additives. The raw material is formed into various varistors geometric dimensions and then sintered under specific atmospheric and ambient conditions at a high temperature. A layer of brass is then flame sprayed on as an electrical contact. Other standard metallized contacts include Aluminum, Copper, Nickel and Silver. In the case of disks, an electrical connection is created by clamping a metal plate to each side of the disk using tie rod. Large assemblies in the case of disks are fashioned using metal plates with tab connections on each side of these disks to create series and parallel stacks of disks to provide appropriate overvoltage protection for high power. Smaller disks simply have tinned copper wires soldered to the brass layer and can be further processed to include a dielectric coating. Geometries are manufactured to suite the electric values required by varying the OD, ID, thickness and length. Our manufacturing process yields good voltage dependences and high energy absorption. Key features of Silicon Carbide Varistors Self-Healing. Used in Air/ Oil/ SF6 Environments. Configurable into Single or Modular Assemblies. Extremely High Ampacity. High Surge Energy Rating. 100% Active Material. Repeatable Non-Linear Characteristic. High Voltage Withstand. Essentially Non-Inductive. SiC Disk Varistors Below is a list of our standard diameter disks 37, 45, 60, 80, 95, and 150mm: Energy absorption per disk ranges up to 122,290J allowing disk assemblies with extremely high energy absorption ratings in the tens of Mega-Joules. Mechanical Parameters Description Abbreviation Range Outside Diameter Do 40 to 150 mm Inside Diameter Di 10 to 30 mm Length L 2 to 25 mm Disk Specifications 150mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 150 21 7.6 250 227 45.2 48130 350 1000 50 405 to 495 1000 5 150 21 10 838 348 59.5 62940 160 1110 50 585 to 715 1000 5 150 21 12.7 400 440 75.6 79600 50 1200 50 810 to 990 1000 5 150 21 12.7 435 478 75.6 79600 100 1350 50 900 to 1100 1000 5 150 21 19 480 528 113.2 114780 150 1500 50 990 to 1210 1000 5 150 21 7.6 1 1 45.2 49680 15000 280 500 50 to 60 25000 3 150 21 7.6 21 19 45.2 49680 30000 700 500 150 to 200 25000 4 150 21 7.6 250 227 45.2 49680 350 1150 50 405 to 495 1000 5 150 21 7.6 275 250 45.2 49680 200 1500 50 250 15 to 45 5 150 21 10 18 17 59.5 65880 30000 440 500 50 to 70  25000 3 150 21 10 383 348 59.5 64960 160 1800 50 585 to 715 1000 5 150 21 12.7 27 24 75.6 82160 30000 950 500 200 to 250 25000 3 150 21 12.7 200 181 75.6 82160 500 1700 50 440 to 660 500 4 150 21 12.7 463 421 75.6 82160 100 2500 50 810 to 990 1000 5 150 21 12.7 602 547 75.6 82160 100 2750 50 900 to 1100 1000 5 150 21 15 2 2 89.3 98180 30000 500 500 80 to 120 25000 3 150 21 15 5 5 89.3 96810 10000 850 500 200 to 250 25000 3 150 21 15 9 8 89.3 96810 10000 1500 500 320 to 440 25000 3 150 21 15 11 10 89.3 96810 10000 1700 500 380 to 570 25000 3 150 21 15 13 12 89.3 96810 10000 2150 500 440 to 660 25000 3 150 21 19 331 301 113.2 122290 1000 2600 50 440 to 660 500 4 150 21 19 23 21 90.5 122290 10000 1800 500 855 to 1045 25000 3 150 21 19 662 602 113.2 122290 150 3400 50 990 to 1210 1000 4   95mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 95 30 10 100 91 37.7 23340 5000 1050 200 100 100 to 200 3 95 30 10 120 109 37.7 23340 5000 1250 200 120 85 to 170 3 95 30 10 150 137 37.7 23340 5000 1450 200 150 65 to 130 3 95 30 10 180 164 37.7 23340 200 850 20 180 55 to 110 4 95 30 10 220 200 37.7 23340 200 1050 20 220 45 to 90 4 95 30 10 270 246 37.7 23340 200 1250 20 270 35 to 70 5 95 30 10 330 300 37.7 23340 200 1450 20 330 30 to 60 5 95 30 25 330 300 94.3 57660 1000 2200 20 330 30 to 60 3 95 30 25 390 355 94.3 57660 500 2500 20 3690 25 to 50 4 95 30 25 470 428 94.3 57660 500 2800 20 470 20 to 40 4 95 30 25 560 509 94.3 57660 50 3100 20 560 18 to 36 4 95 30 25 680 619 94.3 57660 50 3400 20 680 15 to 30 5 95 30 25 820 746 94.3 57660 50 3700 20 820 12 to 24 5 95 30 25 920 837 94.3 57660 50 4000 20 920 11 to 22 5   80mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 80 20 7 232 211 22.1 9900 100 1100 10 220 4 to 12 5 80 20 10 18 16 31.5 16910 10000 390 100 24 340 to 450 3 80 20 10 94 85 31.5 16910 10000 850 100 50 20 to 40 3 80 20 10 80 73 31.5 16910 1000 340 10 80 20 to 40 4 80 20 10 150 137 31.5 16910 1000 630 10 150 20 to 40 4 80 20 10 170 155 31.5 16910 1000 850 10 200 35 to 70 4 80 20 10 220 200 31.5 16910 1000 1050 10 220 24 to 36 4 80 20 10 275 250 31.5 16910 100 1400 10 250 15 to 30 4 80 20 10 308 280 31.5 16910 100 1400 10 365 30 to 50 5 80 20 10 400 364 31.5 16910 100 1700 10 400 12 to 24 5 80 20 10 400 364 31.5 16910 100 1500 10 500 30 to 50 5 80 20 10 350 319 31.5 16910 100 1400 10 500 50 to 100 5 80 20 10 580 528 31.5 16910 100 2200 10 600 10 to 20 5 80 20 10 700 637 31.5 16910 10 3400 100 700 10 to 20 5 80 20 10 700 637 31.5 16910 10 3900 100 700 10 to 20 5 80 20 20 28 26 62.2 32990 15000 900 100 50 150 to 300 3 80 20 20 28 25 62.2 32990 15000 1500 100 75 50 to 100 3 60mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 60 10 2 24 22 3.7 990 100 135 5 36 to 54 100 4 60 10 2 27 25 3.7 990 100 180 5 28 to 42 10 4 60 10 2 33 30 3.9 1020 100 230 5 36 to 54 10 4 60 10 2 38 35 3.9 1020 100 260 5 44 to 66 10 5 60 10 2 49 45 3.9 1020 100 310 5 55 to 81 10 5 60 10 2 66 60 3.9 1020 100 390 5 76 to 114 10 5 60 10 4 82 75 5.8 1480 100 490 5 100 to 150 10 5 60 10 4 104 95 5.8 1480 90 620 5 128 to 192 10 6 60 10 4 115 105 5.9 1520 70 710 5 144 to 216 10 6 60 10 4 132 120 5.9 1520 50 820 5 176 to 264 10 6 60 10 5 154 140 5.9 1520 40 930 5 200 to 300 10 6 60 10 5 176 160 5.9 1520 30 1050 5 240 to 360 10 6 60 10 7 220 200 6.6 1670 20 1300 5 208 to 312 1 6 60 10 7 264 240 6.6 1670 12 1600 5 256 to 384 1 6 60 10 7 297 270 9.9 2470 8 1800 5 320 to 480 1 7 60 10 7 396 360 9.9 2470 4 1750 2 440 to 660 1 7 60 10 7 420 380 9.9 2470 2.5 1900 2 480 to 720 1 7 45mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 45 15 3 21 19 5.3 1600 100 115 5 56 85 to 170 3 45 15 3 25 23 5.3 1600 100 145 5 68 70 to 140 3 45 15 3 47 42 5.3 1600 100 180 5 68 60 to 120 3 45 15 6 68 62 10.7 3100 100 280 5 68 61 to 120 3 45 15 6 82 75 10.7 3100 100 340 5 82 50 to 100 3 45 15 6 100 91 10.7 3100 100 470 5 100 40 to 80 4 45 15 6 120 109 10.7 3100 100 560 5 120 30 to 60 4 45 15 6 150 137 10.7 3100 100 690 5 150 25 to 50 4 45 15 6 180 164 10.7 3100 100 820 5 180 22 to 45 4 45 15 6 330 300 10.7 3100 50 1600 2 330 12 to 24 4 45 15 15 180 164 26.8 7640 100 1000 5 180 22 to 45 3 45 15 15 220 200 26.8 7640 100 1250 5 220 18 to36 3 45 15 15 270 246 26.8 7640 50 1500 5 270 15 to30 3 45 15 15 330 300 26.8 7640 50 1750 5 330 12 to 24 4 45 15 15 390 355 26.8 7640 50 2150 5 390 10 to 20 4 45 15 15 470 428 26.8 7640 50 2400 5 470 8.5 to 17 4 37mm Disks OD ID Thickness Continuous Operating Voltage Max Power Dissipation Max. Energy Absorbtion Max. Pulse Current (80/20us) Typical Production  Level Varistor V/A Exponent mm mm mm Vdc Vrms W J A Peak A Peak Avg A Vdc/Vac mAdc/mAac 1/β 37 10.5 2 26 24 5.6 2080 200 190 10 36 to 54 100 4 37 10.5 2 33 30 5.6 2080 200 220 10 28 to 42 10 4 37 10.5 2 38 35 6.3 2320 200 260 10 36 to 54 10 4 37 10.5 2 49 45 6.3 2320 200 310 10 44 to 66 10 5 37 10.5 2 55 50 6.3 2320 200 370 10 55 to 81 10 5 37 10.5 4 77 70 6.3 2320 200 460 10 76 to 114 10 5 37 10.5 4 93 85 9.2 3280 150 650 10 100 to 150 10 5 37 10.5 4 115 105 9.2 3280 100 790 10 128 to 192 10 6 37 10.5 4 121 110 9.2 3280 80 920 10 144 to 216 10 6 37 10.5 5 143 130 9.2 3280 60 1050 10 176 to 264 10 6 37 10.5 5 165 150 9.2 3280 40 1250 10 200 to 300 10 6 37 10.5 5 198 180 9.9 3520 30 1450 10 240 to 360 10 6 37 10.5 7 231 210 9.9 3520 20 1700 10 208 to 312 1 6 37 10.5 7 275 250 9.9 3520 15 1800 10 256 to 384 1 6 37 10.5 7 330 300 9.9 3520 8 1800 5 320 to 480 1 7 37 10.5 7 430 390 11.3 4000 4 1800 2 440 to 660 1 7 37 10.5 7 460 420 11.3 4000 2 2000 2 480 to 720 1 7 Electrical Parameters Item Range Operating Temperature Range -40 to 150°C TCV (Typical Temperature Coefficient of Voltage) -0.12 to 0.18 %/°C TCI (Typical Temperature Coefficient Current) 0.5 to 0.8 %/°C Specific Heat Capacity Approximately 2 J/cm³/°C Thermal Conductivity 0.07 W/cm² . °C/cm Inductance nH’s (non-inductive) Disk U/I Characteristic Curves

Shielding Effect of Magnetic Field at 50Hz

Thickness of grain-oriented Si (Silicon) steel in the above chart corresponds to one layer of M6 or approximately three layers of M4. For toroidal transformer magnetic shielding is applied to the OD of the transformer. When Si steel is used it is the same as the transformer core material. M6, which is 0.35 mm thick, or M4 which is 0.27 mm thick (3 layers are applied), which equals 0.81mm approximating 0.7mm in the above chart.

Shielding effect of DC magnetic field

Applications

Nanocrystalline Magnetic Shielding has an extremely good weight to noise suppression ratio, making it an excellent choice to mitigate the magnetic noise generated from inductors in electronic devices, which are easily affected by magnetic fields or fluctuating magnetic fields. It is also used for magnetic shielding of buildings adjacent to power lines or power distribution installations.

Nanocrystalline EMI Suppressor Sheet

Halogen-free noise suppression sheet with flame retardance composed of high performance nanocrystalline soft magnetic material. The nanocrystalline material is powered and bonded together with resin and formed into sheets. These sheets have high suppression effect on radiation noise and feature excellent complex relative permeability, resulting in high suppression of radiation noise in the range from 0.1 to 10 GHz.

Sheets are flexible and easy to handle, punch and cut in various shapes. They can even be applied to curved surfaces.

Applications

Highly effective in suppression of radiation noise and cross-talk noise in multilayered circuit boards in various electronic devices, flexible flat cables or on the internal or external surface of a chassis containing digital devices.

Specifications

Ferrite EMI Suppressor Sheet

Thin 0.05 to 0.1mm flexible ferrite EMI suppressor sheets are polymer sheets filled with soft magnetic materials, which offer the highest magnetic permeability of 185µ' at 3MHz and applicable frequency range 100MHz to 6GHz. These are offered in standard roll widths of 210mm x 297mm and come in Halogen Free versions.

Ferrite EMI Suppressor Film

High frequency noise suppressing thin flexible polymer sheets filled with soft magnetic materials. Permeability at 3MHz ranges from 20µ’ to 50µ’ and appliable frequency range 100MHz to 3GHz. Standard thickness of 0.05 to 0.1mm which are offered in standard roll widths of 210mm x 297mm.

These also come in Halogen Free versions.

RF Induction Sheet

A series of flexible soft magnetic materials, which are designed to enhance communication distance of NFC systems and to improve power transfer efficiency of wireless power charging systems. Permeability at 13.56MHz ranges from 25µ’ to 55 µ’ with thickness of 0.1 to 1.0mm. Standard rolls are 210mm wide with lengths up to 15 meters.

Typical applications for RF Induction Sheets are used to increase communication distance of NFC systems (near field communication) or to enhance power transfer efficiency of WPCs (wireless power chargers).

Microwave Absorber

Thin 0.05 to 0.1mm flexible ferrite EMI suppressor sheets are polymer sheets filled with soft magnetic materials, which offer the highest magnetic permeability of 185µ' at 3MHz and applicable frequency range 100MHz to 6GHz. These are offered in standard roll widths of 210mm x 297mm and come in Halogen Free versions.

These can be used for Electronic Toll Collection to improve ETC communication environments (5.8 GHz), reduce RCS of military vessels (8-12 GHz) or for Collaboration Detection and Prevention Systems, to reduce internal (cavity) resonance by isolating antennas from ground plane reflections (24, 77 GHz).