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SLUSAA0 – OCTOBER 2010

Depth of Discharge (DoD) Counters

These counters are used to generate a histogram of the depth of discharge reached at the end of discharge. On

each

transition

from

discharge

to

charge,

the

appropriate

counter

is

incremented

based

on

the

Depth-of-Discharge (DoD = 100% – SoC) if the drain is significant (see description of DoDThresh parameter

below). Note that the increment happens even if the previous cycle did not return to 100% full. Each counter is of

2 bytes and can store values from 0 to 65535.

•

DoD80Count : Counts events where 100%

≥ DoD > 80%

•

DoD60Count : Counts events where 80%

≥ DoD > 60%

•

DoD30Count : Counts events where 60%

≥ DoD > 30%

•

DoD10Count : Counts events where 30%

≥ DoD > 10%

•

DoD0Count : Counts events where 10%

≥ DoD > 0%

The DoD10Count and DoD0Count increment every 16 counts so that the range is 65535 x 16 = 1,048,560.

The DoDThresh parameter sets the threshold (in 0.1 Ah steps) for the capacity drain during a discharge below

which the event does not cause an increment. The capacity drain is calculated as the difference between the

capacity at the beginning of discharge and that at the end of discharge.

Charge Counters

These counters calculate the cumulative charge in and out of the battery. These data are stored in 2 bytes in

steps of 16 Ah. Thus the maximum value stored is 65535×16 Ah or 1,048,560 Ah, which is equivalent to >3495

full discharge cycles of a 300-Ah battery.

ChargeAH: Cumulative amp-hours in to the battery (includes charge efficiency compensation using the ChgEff

parameter)

DischargeAH : Cumulative amp-hours out from the battery.

Discharge Time Counter

This counter records the cumulative time in discharge mode. As with the abuse counters, this counter increments

every 6 minutes This counter is of 2 bytes and can store values from 0 to 65535. This range permits a maximum

time of 273 days to be recorded.

Copyright © 2010, Texas Instruments Incorporated

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