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Model 456 - Temperature Controlled Standard Resistor
Isotech, Model 456 - Temperature Controlled Standard Resistor
 
  • Nominal Temperature Coefficient of Resistance: +0.02ppm/C (with temperature control on) 18 to 25C
  • Current Noise: <0.010μV (RMS) / Volt of Applied Voltage.
  • Thermal EMF: 0.1μV/C Max; 0.05μV/C Typical
  • The most precise and stable resistors available.
  • Impervious to harmful environments - oil filled.

Product Code: 456
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   Product Description    Specifications
 

Temperature Controlled Standard Resistor

Temperature Controlled Fixed AC/DC Resistors - Isotech 456

By temperature controlling an otherwise very stable resistor, a performance close to the very best available in the world can be achieved at a surprisingly low price. The resistor itself is oil filled and hermetically sealed.

The function of hermetic sealing is to eliminate the ingress of moisture and oxygen both of which play a role in the long term degradation of unsealed resistors. A further enhancement in both short and long term stability is achieved by oil filling. The oil also acts as a thermal conductor allowing the device to accept short periods of overload without degradation.

With accuracies of 0.005% and a resistance range from 5Ω to 3.3 MΩ and long term drift of less than 5ppm, these devices are virtually secondary standards that can be kept in a laboratory as references to calibrate other devices.

The Resistor is held in a temperature controlled environment heated to 300.1C other temperatures are available to special order. The heater requires 2 watts at 5V which can be supplied by a battery or an unregulated DC supply. In an ambient of 20C the Resistor's heater will warm up in typically 30 minutes, and a LED shows when the temperature has been reached. A test pocket is provided so that the resistors' temperature can be monitored if required.

0.1 ppm/month or better stability can be expected.

We can supply the value you choose 0.1% between a minimum of 5Ω and a maximum of 3.3 megaΩ. However we bulk buy and keep in stock the following standard values: 10W, 25W, 100W, 1000W, 10,000W.

For the highest quality traceability we recommend that the 456 be UKAS Certified. We can offer the 2 Sigma Uncertainties shown in the table.
  • Nominal Temperature Coefficient of Resistance: +0.02ppm/C (with temperature control on)18C to 25C
  • Power Rating: 0.5 watt at +25C
  • Resistance Tolerance (Initial Resistance Accuracy): 0.005%
  • Resistance Range: 5Ω to 3.3 MΩ
  • Current Noise: <0.010V (RMS) / Volt of Applied Voltage
  • Thermal EMF: 0.1V/C Max; 0.05V/C Typical
  • The most precise and stable resistors available
  • Impervious to harmful environments - oil filled


Literature
Model 456 Datasheet