Fluke dd cpem02 free download

File name dd_cpem02.pdf

THIN FILM DESIGNS FOR 1000V AC RANGE RESISTORS David Deaver Fluke Corporation POB 9090 Everett, WA 98206 Abstract resistor. The most effective shields provide decreasing field strength longitudinally along the resistor resulting Alternatives to the traditional coaxial design of precision in no current flow in the capacitance to the shield. ac range resistors have resulted in performance breakthroughs, reducing both ac-dc difference and These coaxial resistors usually have very high thermal settling times. Application of thin film resistor resistance to ambient resulting in very long settling technology and innovative thermal design has made times. When used with a 5mA TVC, the 1000V range these advancements possible. resistor would dissipate 5W, easily resulting in 50-100 degC temperature rise. Introduction In the past decade, national measurement institutes Thin Film 1000V Range Resistor Designs (NMIs) have focused on resolving their differences in the For the thin film designs, dimensional stability is much vicinity of 1000V, 100kHz. These differences used to be better allowing smaller enclosures. In addition, since the considerable. resistors are planar, a rectangular enclosure works nearly as well as the coaxial design making mounting and Accredited by NVLAP in 1995, the Fluke Primary reducing thermal resistance much easier. Standards Lab sought an additional accreditation by the German DKD in 1997. They accepted most of the claims already approved by NVLAP with standards traceable to either the NIST or the PTB. However, the claims made 792A c d 5790A for 1000V at higher frequencies could only be accepted i k e a if standards were calibrated at the accrediting body's g b associated N