Reference standards for ac-dc voltage and current transfer
Project Description
SP and METAS have agreed on cooperation in upgrading of each others reference standards for ac-dc voltage and current transfer. METAS has knowledge in designing and manufacturing range resistors for thermal voltage converters and SP has corresponding knowledge in current shunts for ac-dc current transfer and power measurement. In the project SP will manufacture a set of current shunts with ranges from
Final Report 2007-05-29
SP and METAS have had cooperation in upgrading each others reference standards for ac-dc voltage and current transfer.
METAS has designed and made range resistors from 2 V to 1000 V for a new thermal voltage converter set of SP. The range resistors together with the PMJTCs of SP have been adjusted for minimum ac-dc transfer difference and calibrated by comparison with the reference standard of METAS. The range resistors were delivered to SP in 2006.
SP has designed and made current shunts from 20 mA to 20 A for a new thermal current converter set of METAS. The shunts are designed to minimize the phase angle error and can also be used as current sensors in a power measuring system. The dc-resistance, ac-dc transfer difference and inductance of the shunts have been calibrated by SP. The phase angle error of the shunts is determined from the measured inductance. The shunts are now delivered to METAS.