MIL-HDBK-1004/10

e)

Sizing rectifier requirements:

dc current - 57.13 A

Anode circuit resistance - 0.508 ohms

dc voltage = IR = 57.13 x 0.508 = 29 V

A standard rectifier in this range has an output of 90 A at 42 V.

f)

Anode bed design (shore side):

Select 2- by 60-foot anodes.

For current distribution, a distributed anode system should be used.

Compare resistances of single anodes with and without backfill:

Without backfill:

R=

(P/L)K

where

R = electrolyte-to-anode resistance for a single vertical

anode.

P = 1,000-ohm cm soil resistivity

L = 5-foot anode length

K = 0.0234 factor for length to diameter (refer to para.

6.2.1.4)

R = (1000/5)0.0234

R = 4.68

With 10-inch diameter backfill in hole:

R = (P/L)K

where

R = electrolyte-to-anode resistance for a single vertical

anode

P = 1,000-ohm cm soil resistivity

L = 10-foot backfill length

K = 0.0186 factor for length to diameter (refer to para.

6.2.1.4)

R = (1,000/10)0.0186

R = 1.86 ohms

Since backfill is required to reduce the resistance below 2 ohms, backfill is

required.

g)

Minimum weight of anodes required for 15-year life (shore

side).

W=

YSI

205

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