CDC STACKS serves as an archival repository of CDC-published products including scientific findings, journal articles, guidelines, recommendations, or other public health information authored or co-authored by CDC or funded partners.
As a repository, CDC STACKS retains documents in their original published format to ensure public access to scientific information.
i
Distinguishing motor starts from short circuits through phase- angle measurements
-
1997
-
Series: NIOSH Numbered Publications
Details:
-
Personal Author:
-
Corporate Authors:
-
Description:"An investigation was undertaken to investigate the characteristics of high voltage underground electrical mining equipment motor start and short circuit waveforms. The aim of the study was to determine a method for providing short circuit protection without intentional time delays to account for motor starts. Computer simulations of power systems identified the requirement for accurate and rapid detection systems. Analyses of high voltage longwall coal mine power systems were conducted using commercial power system analysis software. Distribution voltage, transformer impedance, power center location, and motor size affected magnitude of short circuits and motor start currents. Phase angles between voltage and current were longer for motor starts than for short circuits. A prototype with an induction motor was developed and tested in the laboratory. Minimizing the intentional time delays in short circuit protection will help ensure temperatures of ignition thresholds for gas and dust are not be exceeded on energized electrical apparatus surfaces." - NIOSHTIC-2
-
Content Notes:Michael R. Yenchek, James C. Cawley, Jeffrey Shawn Peterson, and Jeffrey L. Kohler.
Investigation by the Pittsburgh Research Center (PRC).
Includes bibliographical references (p. 9).
-
Subjects:
-
Series:
-
Subseries:
-
Document Type:
-
Genre:
-
Pages in Document:print; 11 p. : ill. ; 28 cm.
-
NIOSHTIC Number:00238990
-
Resource Number:DHHS (NIOSH) Publication No. 97-120; RI-9638
-
Collection(s):
-
Main Document Checksum:
-
Download URL:
-
File Type: