Ohm-Labs 200 series reference resistance standards

The Ohm-Labs 200 Series reference resistance standards are designed to maintain Ohm at a level of 0.1 ohms to ten megohms.

Each standard up to 1k is individually wound from selected Evanohm alloy wire, which has been carefully heat-treated for extremely low temperature coefficients of resistance and excellent long-term stability.

Above 1k, a polycarbonate top reduces any leakage errors, and the connections have shielded BPO connectors, which are connected to an internal shield. These models can be used as 4-wire, 2-wire or shielded standards. An internal 10 K thermistor temperature sensor is also included.

The initial 1 ohm standard (model 200 Series reference resistance standards) showed stability of <0.1 ppm/year, and (alpha) temperature coefficient of <0.05 ppm/°C at 25.00°C, and without measurable barometric effect.

Each standard is manufactured separately, and can be supplied optimized for 25 °C, 23 °C or 20 °C. Because they are filled with oil and hermetically sealed, these standards are highly immune to changes in air pressure and relative humidity.

All models have an ISO17025 accredited calibration, with temperature coefficient data.

In addition to ten decade values, the 200 series are offered as -T values for thermometry and -Q values for use with a Quantum Hall System.

Models: