U.S. Resistor utilizes 2 different base materials to manufacture our Ceramic Resistor Disc / Washer and Rod / Tubes.
Our original material has Zirconium Silicate as the base material and has the prefix of 83-xxxx to designate for this material.
We now offer Alumina as a base material and has the prefix of 85-xxxx to designate for this material. The Alumina offers a lighter weight material which can be significant on many applications but offers the same electrical characteristics as the original Zirconium Silicate material.
Ceramic resistors are manufactured from a sintered body of ceramic material, with conductive particles distributed throughout the matrix, to produce a resistor that is 100% active and non-inductive. Ceramic resistors are chemically inert. They can withstand high-energy and high-voltages at high temperatures, such as those encountered in the protection of high voltage surge equipment, discharge banks, and in high frequency radiation suppression.
| Resistivity Range | 83 – Zirconium Base | 0.8 to 4,000 Ohm-in 2 to 10,000 Ohm-cm |
| 85 – Alumina Base | 2 to 4,000 Ohm-in 5 to 10,000 Ohm-cm |
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| Maximum Steady State Power Density |
12 watts/in³
0.75 watts/cm³ |
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| Maximum Transient Energy Density | 4,920 joules/in³ 300 joules/cm³ |
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Maximum Voltage Gradient
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10 kV/in
4 kV/cm |
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Maximum Rate of Power Injection
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150,000 watts/sec/in³
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Maximum Rate of Current Injection
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1,000 amps/in² - Contact Area
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Maximum Operating Temperature
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250° C
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Voltage Coefficient
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- 0.3% to - 7.5% /kv/cm
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Temperature Coefficient
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- 0.03% to - 0.16%/°C
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Heat Dissipation
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2.86 watts/in²
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Thermal Conductivity
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0.03 cal / cm. sec 0C
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Specific Heat
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0.2 cal/gm/°C
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Coefficient of Thermal Expansion
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4 x 10-6
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Heat Capacity
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8.7 cal/°C/in³
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| Density (Nominal) | 83 – Zirconium Base | 2.55 g/cc |
| 85 – Alumina Base | 2.30 g/cc |