Passive Component Applications Resistor Solutions for Energy Metering 2006

TT electronics Supplier of electronic and electrical components to the world’s leading companies

TT electronics (Components) Resistive Components Sensors Hybrids AB Sites Salzburg; Werne; Klingenburg FE offices; Japan; Malaysia; Singapore USA sites; Corpus Christi; Boone; Smithfield Europe offices; UK, France, Germany, Italy Magnetic Materials Wound Components Optoelectronics

Welwyn Components, UK 1937: Started Resistor Manufacture in Welwyn Garden City near London 1948: Moved to Northumberland, near Newcastle 1960: Started Hybrids Manufacture 1990: Acquired By TT Group 2001: TT became “TT electronics plc”

Welwyn Components, UK Applications Engineering Contacts Custom & new products Special testing Pulse performance data Applications support Stephen Oxley stephen.oxley@welwyn-tt.com Direct: +44 (0)1670 536731 Martin Birkett martin.birkett@welwyn-tt.com Direct: +44 (0)1670 536723

Passive Components Applications Agenda Welwyn Resistive Components for energy metering applications Line Input Resistor Voltage Measure Current Sense Lead-forming Options for lower assembly costs

Applications: Industrial

Welwyn Applications: Industrial Energy Meters Motor Drives Power Supplies Lighting Ballasts

Energy Meters Applications: Industrial Current Line Input Sense Flameproof Wirewound Low Ohmic LRF OAR ULR WP-S Current Sense Line Input Flameproof Oxide Energy Meters WMO-S Precision High Voltage WRM RC MH VRW Voltage Measure

WP-S Flameproof Wirewound High Purity Ceramic Core improves axial heat spread Welded Cap Construction Pb-free Finish on Cu-clad steel wire Flameproof Cement Coat UL94-V0 Silicone Cement Energy absorbing winding Custom choice of alloy & wire diameter

WP-S Flameproof Wirewound WP-S Features 25% to 50% reduction in size Custom design for specific inrush ratings Fuses without flame or particles Operating ambient -55 to +155°C Sizes from 1W to 7W Competitor Competitor WP-4S

WP-S Flameproof Wirewound WP-S Features Surface mount option – Z-form (e.g. WP2Z) Pick & place from tape Full wirewound rating & pulse performance in SMD format

WMO-S Pulse / Failsafe Oxides Pulse withstanding fusible oxides Defined 1.5/50us pulse performance Defined line voltage pulse performance Defined line voltage failsafe fusing

WMO-S Pulse / Failsafe Oxides How do we get WMO-S performance? Tin Oxide film for good pulse capacity Careful control of laser adjustment parameters Continual batch monitoring of pulse and fusing performance

High Pulse Performance

Energy Meters Applications: Industrial Current Line Input Sense Flameproof Wirewound Low Ohmic LRF OAR ULR WP-S Current Sense Line Input Flameproof Oxide Energy Meters WMO-S Precision High Voltage WRM RC MH VRW Voltage Measure

Compact high voltage MH/VRW Sizes -25 (1.6kV) & -37 (3.5kV) Small size High pulse load capability MH thin film, VRW thick film Value up to 30M

MELF for high accuracy – typically 4 to 6 parts in series Compact precision WRM MELF for high accuracy – typically 4 to 6 parts in series 0102 / 0204 / 0207 sizes High stability metal film Ideal for measurement circuits TCR to 5ppm Tolerance to 0.1%

Precision Through-Hole

Energy Meters Applications: Industrial Current Line Input Sense Flameproof Wirewound Low Ohmic LRF OAR ULR WP-S Current Sense Line Input Flameproof Oxide Energy Meters WMO-S Precision High Voltage WRM RC MH VRW Voltage Measure

LRF Series Current Sense LRF Features Low ohmic values to 3mW Power rating to 3W Higher thermal conductivity than metal strip Lower inductance than capped metal strip Also LRZ zero ohm jumpers to 35A Now includes smaller sizes to 0402 as LRCS

LRF Series Current Sense Low thermal impedance gives lower temperature rise Thermal photographs of 2010 parts at 1W 20 40 60 80 100 Metal Strip LR 83°C/W 58°C/W Using 200mm2 pad / trace areas as heatsink

OAR Series Current Sense OAR Features Compact metal element shunt Power rating to 5W, values from R005 Welded copper terminations

ULR Series Current Sense ULR Features Ultra-low ohmic values to 0.5mW Power rating to 3W Low inductance welded metal strip New

Standard Lead-forming Options

Application Note

The End Thank you! Any questions?