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MlL-HDBK-419A
(5) Verify that the color of the identified conductor is white or natural gray. If larger than a
No. 6 AWG and of a different color (not green), it should be reidentified white or natural gray with paint or
tape, or by other means such as tags or labels.
(6) Verify that the equipment grounding conductors ("safety" or "green" wire) are green or green
with one or more stripes, or if larger than No. 6 AWG and of a color other than green, not white, has been
reidentified with green tape, paint, or other means.
(7)
Verify that all metal noncurrent carrying service equipment is effectively bonded by one of
the methods specified below and that all non-conductive coating in the bonding path has been removed:
(a)
(b) Threaded couplings and threaded bosses on enclosures with joints that are tight when
rigid conduit is involved.
(c)
Threaded coupling used for metallic tubing and rigid conduit is tight.
(d) Bonding jumpers are used around knockouts that are punched or otherwise formed so as
to impair the electrical connection.
(e)
Bonding-type locknuts and bushings on other devices.
(6) Verify that all covers for wireways, junction and pullboxes, surface raceways, etc., are
installed and secured.
(9) Using a clamp-on ammeter, measure the current in each phase conductor and the identified
service conductors. Also measure the current in the grounding electrode conductor. Record the current levels
and wire sizes on Part IV of the survey form in Chapter 2.
Separately derived power sources. For premises derived sources, (a premises wiring system with
b.
power derived from an on-site generator, transformer or converter windings that have no direct electrical
connection to supply conductors originating in another system) perform the following for each source.
(1)
Verify that the neutral conductor is grounded where the following exists:
(a)
AC circuits of less than 50 volts (peak to peak) where:
1.
Supplied to transformers if the transformer supply system exceeds 150 volts (peak
to peak) to ground.
Supplied by transformers if the transformer supply system is ungrounded.
2.
3.
Installed as overhead conductors outside of buildings.
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