UFC 3-570-06
JANUARY 31 2003
5-2.3
Anode Lead Wires. With power OFF, disconnect anode lead(s) at P4.
Using an alternative isolated metallic structure (isolated from structure being tested; if
doubt exists, measure continuity to structure lead), such as a metal culvert or fence, or
install temporary ground rods, and connect to P4 (positive terminal). For a short period
of time, turn power ON and note AC current (paragraph 5-2.2). One of two conditions
exists: either current is now present (changed); or it is not present (not changed).
Note: If the structure being tested is the inside of a water tank or tower, and the lack of
water will not allow current flow (no electrolyte), fill the tank, and then retest.
5-2.3.1
Current is Present. If current exists, the anode lead is broken or the anodes
have failed (proceed to paragraph 5-2.8).
5-2.3.2
Current is Not Present. If no current exists, the structure lead may be
broken (proceed to paragraph 5-2.4).
5-2.4
Structure Lead. For this test, the temporary or alternative anode should
remain connected to terminal P4 as described previously in paragraph 5-2.3. With
power OFF, disconnect structure lead at N4. Using an alternative isolated metallic
structure (isolated from structure being tested, if doubt exists, measure continuity to
structure lead), such as a metal culvert or fence, or install temporary ground rods, and
connect to N4 (negative terminal). For a short period of time, turn power ON and note
AC current (paragraph 5-2.1). One of two conditions exist, either current is now present
(changed) (proceed to paragraph 5-2.4.1); or it is not present (not changed) (proceed to
paragraph 5-2.4.2).
5-2.4.1
Since current is now present, the structure connection is broken. Use the
fault detector and cable locator, connected directly to the structure lead at N4, to trace
the structure lead from the rectifier towards the structure. This can be extremely difficult
in some cases. An alternative method is to locate the first structure connection (from
drawings, markers, or induction methods). Excavate to the structure and measure
continuity back to the rectifier using a cathodic protection multi-combination meter
continuity check circuit. Use the fault detector and cable locator, connected directly to
the structure lead, to trace the lead from the structure towards the rectifier. If this is still
unsuccessful, replace the structure lead from the rectifier to the structure.
isolated ground for the fault detector or cable locator to put a strong locator signal on
the cable under test.
5-2.4.2
If current still does not exist (not changed), the temporary anode bed is not
sufficient. Supplement the temporary anode bed, then repeat paragraph 5-2.3.
5-2.5
AC Voltage to Stacks. Measure the AC voltage input to the stacks of the
5-7
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