which is -radiated and an unnecessarily large set-
around the perimeter of the buildings. These
ting could cause excessive radio interference,
grounds can be made with metal pipe or ground
rods, and a good copper braid connection should be
(2) Make sure that the spark gaps of the high
made from the ground rod to the metal walls of
frequency unit are at the smallest setting which
the building. For best results, the earth around
will give satisfactory welding results. The recom-
these ground rods should be treated.
mended maximum gap setting is 0.006 inches.
f. Grounding the Welding Circuit.
(3) Use the shortest welding leads which can
conveniently be used. Keep the welding leads or
(1) Ground selection.
near the floor.
(a) Proper grounding of the welding cir-
(4) Properly ground the welding circuit in
cuit will greatly reduce the interference in most
accordance with the instructions given,
cases. It is very important that not more than one
ground be used anywhere in the welding circuit.
( 5 ) Many high frequency stabilized arc
Tests have shown that the best place to make the
welder installations have been made in small cor-
ground connection in the. welding circuit is usually
rugated-iron buildings. While such buildings are
to the work terminal of the welder.
supposed to act as shields to prevent radiation, it
(b) This ground should be as short and as
has been found that unless the building is properly
direct as possible.
grounded, it may actually act as a radiator. There-
fore, it is advisable to provide several grounds
(c) Water pipes, electrical conduit systems,
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