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ETL 1110-9-10(FR)
5 Jan 91
I' =
8.0 mA/sq ft (Required current
density for riser pipe from item 9
of paragraph 2-7a)
CE =
0.0 (Coating efficiency.
Inner
surfaces will be uncoated, from item
7 of paragraph 2-7a)
IR =
1806 sq ft x 8.0 mA/sq ft x (1.0 -
0.0).
IR =
14,448 mA; use 14.5 amp.
5)
Select the number of anodes required for the bowl, to
meet the anode system's 20-year design life using
equation 1-2:
N=
I
IA
Where:
I=
19
amp
(Current
requirement
determined in step 3)
IA =
1 amp/anode (Current rating per
anode from table 3-3 for 4-ft long
by 0.138-in. diameter ceramic rods)
N
=
19
1
N
=
19 rod segments (4-ft long segment)
6)
Select the number of anodes required for the riser to
meet the anode system's 20 year design life using
equation 1-2:
N=
I
IA
Where:
I=
14.5
amp
(Current
requirement
determined in step 4)
IA =
1 amp/anode (Current rating per
anode from table 3-3 for 4 ft long
by 0.138-in. diameter ceramic rods)
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