Ohm-Labs Hamon transfer standards are built on Leeds & Northrup's 'a commercialized B.V. design. Hamon's. We offer Hamon's 4321 and 4322 transfer standards, and the pair allows transfer from 1Ωto 10kΩ. The same design can be provided with the 4322 built with 100Ωresistors.
A 100:1 accuracy of 0.01ppm has been calculated.
Each device contains 10 nominal identical ones permanently connected in series. The commutator connects the resistors in parallel thus providing 1/100th of the series resistance.
Two optional commutators are available: 1/10 or 1/4.
The internal resistors are constructed from carefully selected wires for adequacy between temperature and power coefficients. The housing is sealed to provide resistance to changes in pressure and relative humidity.
Each 4321 10ΩHamon features a parallel commutator.
Detailed specifications can be found in the "Downloads" tab.