Walker Magnetics TURBOMILL 40B - Manual (Page 9)

O.S. WALKER Co. Inc., Turbomill Electroperm Chucks
DD15508M.doc Rev. ~, September 17, 2002
2-4
2.4 Electrical Ground
ELECTRICAL GROUNDING
Because the O. S. Walker Co. does not know the specifics of each application and installation of
these products and the electromagnetic device to which they are attached, it can only warn the
installer and user that the electrically conductive body of the electromagnetic device MUST be
connected to a proper electrical ground.
According to ANSI/NFPA 79 1997(an American National Standard) "Electrical Standard for
Industrial Machinery":
•
Section 19.3 Equipment Grounding: The machine and all exposed noncurrent-carrying
conductive parts, material, and equipment, including metal mounting panels that are likely to
become energized and are mounted in nonmetallic enclosures, shall be effectively grounded.
•
Section 19.2.4 Grounding Conductors: It shall be permissible to use machine members or
structural parts of the electrical equipment in the grounding circuit provided that the cross-
sectional area of these parts is at least electrically equivalent to the minimum cross-sectional
area of the copper conductor required.
•
Section 19.6.1 Continuity of the Grounding Circuit: The continuity of the grounding circuit
shall be ensured by effective connections through conductors or structural members.
•
Section 19.6.3 Continuity of the Grounding Circuit: Moving machine parts, other than
accessories or attachments, having metal-to-metal bearing surfaces shall be considered as
bonded. Sliding parts separated by a non-conductive fluid under pressure shall not be
considered as bonded.
PRIOR TO ENERGIZING THE ELECTROMAGNETIC DEVICE, CHECK ALL THE ELECTRICAL
CONNECTIONS AND CONFIRM THAT THE METAL BODY OF THE ELECTROMAGNETIC
DEVICE IS ELECTRICALLY GROUNDED.