electrical contact with the frame; in other words, grounded. If the lamps
do not light, connect the wire to a terminal block, die or slide. If the
lamps then light, the circuit, coils or leads are in electrical contact
with the large coil in the transformer or its connections.

If, however, the lamps do not light in either case, the lamp cord should be
disconnected from the switch and connected to the other side, and the
operations of connecting to welder frame, dies, terminal blocks, etc., as
explained above, should be repeated. If the lamps light at any of these
connections, a "ground" is indicated. "Grounds" can usually be found by
carefully tracing the primary circuit until a place is found where the
insulation is defective. Reinsulate and make the above tests again to make
sure everything is clear. If the ground can not be located by observation,
the various parts of the primary circuit should be disconnected, and the
transformer, switch, regulator, etc., tested separately.

To locate a ground in the regulator or other part, disconnect the lines
running to the welder from the switch. The test lamps used in the previous
tests are connected, one end of lamp cord to the switch, the other end to a
binding post of the regulator. Connect the other side of the switch to some
part of the regulator housing. (This must be a clean connection to a bolt
head or the paint should be scraped off.) Close the switch. If the lamps
light, the regulator winding or some part of the switch is "grounded" to
the iron base or core of the regulator. If the lamps do not light, this
part of the apparatus is clear.

This test can be easily applied to any part of the welder outfit by
connecting to the current carrying part of the apparatus, and to the iron
base or frame that should not carry current. If the lamps light, it
indicates that the insulation is broken down or is defective.