US 12,089,333 B2
Electricity meter
Andrew Nicholas Dames, Cambridge (GB); Dawei Zhi, Cambridge (GB); and Joseph Adam, Impington (GB)
Assigned to SENTEC LTD, Cambridge (GB)
Appl. No. 17/295,582
Filed by SENTEC LTD, Cambridge (GB)
PCT Filed Nov. 20, 2019, PCT No. PCT/GB2019/053285
§ 371(c)(1), (2) Date May 20, 2021,
PCT Pub. No. WO2020/104797, PCT Pub. Date May 28, 2020.
Claims priority of application No. 1818876 (GB), filed on Nov. 20, 2018; and application No. 1904763 (GB), filed on Apr. 4, 2019.
Prior Publication US 2022/0022322 A1, Jan. 20, 2022
Int. Cl. H05K 1/11 (2006.01); G01R 15/18 (2006.01); G01R 21/06 (2006.01); H05K 1/02 (2006.01); H05K 1/16 (2006.01)
CPC H05K 1/165 (2013.01) [G01R 15/185 (2013.01); G01R 21/06 (2013.01); H05K 1/0259 (2013.01); H05K 1/115 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An electricity meter comprising:
a conductor for transferring energy from a supply to a load;
a multi-layer printed circuit board mechanically attached to the conductor, the multi-layer printed circuit board comprising:
two or more insulating layers, the two or more insulating layers comprising a first insulating layer having an attachment surface facing the conductor, wherein the attachment surface is mechanically attached to the conductor directly or indirectly;
a first conductive layer comprising a first planar sensor coil, wherein the first insulating layer is between the first conductive layer and the conductor;
a second conductive layer comprising a second planar sensor coil;
a second insulating layer between the first and second conductive layers;
wherein the first planar sensor coil and the second planar sensor coil are electrically connected to one another by:
a buried via; or
a blind via extending inwards from a back surface of the multi-layer printed circuit board, the back surface being opposed to the attachment surface;
wherein a creepage distance across the surface of the multi-layer printed circuit board between the conductor and an exposed electrical connection of the multi-layer printed circuit board is greater than or equal to 7 mm.