Study on the Prevention of Electro-Magnetic Fields Using a Bi-Digital O-Ring Test (Mk-IV) Hauling Machine

Abstract

Objective:

In this study, we examine the conditions that prevent electromagnetic fields in the measurement environment and the fingers forming the O-Ring during the Bi-Digital O-Ring (BDOR) test.

Subjects:

The BDOR-test can detect normal or abnormal functions through an O-Ring formed by two selected fingers. However, the assistance of an alternate examiner is required for diagnosis without a third person or an animal in the field.

Materials & Methods:

1) Hauling machine functions are concerned with linear changes at a speed of 90-180mm/s and force of 5-27.5kg·f, when the O-Ring is towed. 2) A Shaheild screen chamber, mesh knitting, was positioned to protect the measurement environment from exposure to the electromagnetic field. 3) A rubber sheet was spread over the hexahcdral mesh floor. 4) The electromagnetic field from the Mk-IV BROR-Test machine was checked during operation using a visual display unit (5Hz-2KHz) (KEC), in accordance with the Sweden Standards (MPR-1990.8). 5) Laboratories were inspected using a Fauser FM-6 (made in Germany).

Results:

1. Changes in the electromagnetic field during cycles of turning on/off the shield function of BDOR-test machine were detected in the Shaheild screen chamber (upon turn-off: n=6, X=60.166v/m; upon turn-on: n=6, X=0.333v/m). These changes translated into a protection rate of 99.5%. 2. The results of the BDOR-test, which was conducted in KEC in accordance with the Sweden Standards, showed a very stable progress of the noise levels (0.05v/m) during cycles of turning on/off the personal computer and foot switch.

Discussion:

The silver screened chamber, with covered hexahedron, and the electromagnetic wave hauling machine were simultaneously connected to keep the measurement environment away from exposure to the electromagnetic field. The effects of this positioning were remarkable. A rubber plate was placed on the floor to prevent the examiner from contacting to the floor earth. The printer, without an earth terminal was maintained outside the screen chamber (8.5-10.5v/m). Differences between the individual measurements and the standard values were compared for the evaluation of data.