200 series Standards
- OUR BEST RESISTANCE STANDARDS
- LOW TEMPERATURE COEFFICIENTS
- HIGH STABILITY
- IMMUNE FROM HUMIDITY OR BAROMETRIC ERRORS
- MAY BE USED IN OIL OR AIR
Ohm-Labs' 200-Series Reference Resistance Standards are designed for maintaining the ohm at levels from 1 ohm to10 megohms.
Each standard is individually wound from selected Evanohm alloy wire, which has been carefully heat treated for low temperature coefficients of resistance and processed for long term stability.
Standards 100 K and above have internal guarding, and may be used as 4-wire, 2-wire or guarded standards. An internal 10 K thermistor temperature sensor is also included.
Tests on one ohm standards (model 200) have shown long term stability (after first year settling) of <0.1 ppm / year. Temperature coefficient is typically<0.05 ppm / °C at 23.0 or25.0 °C, and there is no measurable barometric effect.
Each standard is individually optimized for 20, 23 or 25 °C use.
Oil-filled and hermetically sealed, these standards are highly immune from changes in barometric pressure and relative humidity.
All models include ISO 17025 accredited calibration, with temperature coefficient data.
In addition to decade values, the 200-Series are offered in –T values for thermometry, and –Q values for use with a Quantum Hall System.
All Ohm-Labs resistance standards are warranted five years.
Special values are available upon request.
| Model Number |
Nominal Resistance |
Tolerance in ppm |
Rated Current |
Typical Coefficients | Typical 12 mo. Stability |
| 200 | 1 | <2 | 100 mA | Temperature α < 0.1 ppm / °C β < 0.01 ppm / °C Voltage < 0.1 ppm / V Pressure < 0.001 ppm / kPa |
< 0.1 ppm |
| 201 | 10 | <2 | 30 mA | < 0.2 | |
| 201-T | 25 | <2 | 25 mA | < 0.3 | |
| 202 | 100 | <2 | 10 mA | < 0.2 | |
| 203 | 1 K | <3 | 3 mA | < 0.2 | |
| 203-Q | 6.4 K | <5 | 1 mA | < 0.3 | |
| 204 | 10 K | <2 | 1 mA | < 0.2 | |
| 204-Q | 12.9 K | <10 | 1 mA | < 0.3 | |
| 205 | 100 K | <5 | 0.3 mA | < 0.3 | |
| 206 | 1 Meg | <5 | 0.1 mA | < 0.5 | |
| 207 | 10 Meg | <10 | 0.03 mA | < 1 |
Notes
- Tolerance is accuracy at time of manufacture
- Temperature coefficient is at specified 20, 23 or 25 °C +/-5 °C.
Physical
- 127 mm dia. x165 mm high (5" x 6.5"); 4.5 kg (10 #)
