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STANDARD RESISTORS |
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RW
Wilkins Standard Resistors. High accuracy
< 20 ppm. |
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RW Wilkins Standard
Resistors.
RW Wilkins Standard
Resistors are made from a specially selected alloy
having a low temperature coefficient mounted in a strain free manner, on
formers made from a material of low dielectric loss but of high
mechanical stability. All connections are welded. Prolonged heat
treatment of the elements ensures long term stability and low
temperature coefficient of resistance. The elements are hermetically
sealed in stainless steel containers which are first evacuated and then
filled with dry oil (No.4 Kerosene).
Provision is made for inserting a
thermometer, but the resistors are intended to be used in a controlled
temperature oil bath
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High Accuracy, <20ppm
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Excellent long term stability
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Low temperature coefficient
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Rugged stainless steel construction
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Maximum dissipation for the resistors is 1 watt, but the
highest performance will be obtained with dissipation limited to 10
milliwatts, which is the ideal working condition.
No damage will occur
if the dissipation is increased to 1 watt, but self heating will affect
the resistance value after a few minutes.
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Specification |
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| Tolerance |
±20ppm |
| Test certificate |
3 ppm for 1, 10, 100 & 1000 Ohms
5 ppm for 25 Ohms |
| Optional calibration |
Up to ±0.1ppm, depending on
calibration laboratory |
| Stability |
2 ppm per year |
| Temperature coefficient |
Typically 2 ppm/°C |
| Frequency dependence |
1 ppm up to 1592Hz |
| Working temperature |
20°C, but within the range of 15°C
to 40°C |
| Dissipation |
10 milliwatts (recommended), 1 watt
(maximum) |
| Load coefficient |
Approximately 6 ppm / watt |
| Dimensions / weight |
Diameter: 76mm, Height: 114mm,
Weight: 3.3 kg. |
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ORDER CODES
RWx where x is 1, 10, 25, 100 or 1000 ohms.
RWTE1 Thermal enclosure for RW resistor, 36°C fixed.
RWTE2 Thermal enclosure for 2 RW resistors, 40°C max. factory set.
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