7.1.4. Tail current
The battery is considered as “fully charged” once the charge current has dropped to less than the set “Tail current” parameter.
The “Tail current” parameter is expressed as a percentage of the battery capacity.
Remark: Some battery chargers stop charging when the current drops below a set threshold. In these cases, the tail current must
be set higher than this threshold.
As soon as the battery monitor detects that the voltage of the battery has reached the set “Charged voltage” parameter and the
current has dropped below the “Tail current” for a certain amount of time, the battery monitor will set the state of charge to 100%.
Default setting
Range
Step size
4.00%
0.50 - 10.00%
0.1%
7.1.5. Charged detection time
This is the time the “Charged voltage” and “Tail current” must be met in order to consider the battery fully charged.
Default setting
Range
Step size
3 minutes
0 - 100 minutes
1 minute
7.1.6. Peukert exponent
Set the Peukert exponent according the battery specification sheet. If the Peukert exponent is unknown, set it at 1.25 for lead-acid
batteries and set it at 1.05 for lithium batteries. A value of 1.00 disables the Peukert compensation. The Peukert value for lead-
acid batteries can be calculated. For more information on the Peukert calculation, battery capacity and Peukert exponent see the
Peukert exponent chapter.
Default setting
Range
Step size
1.25
1.00 - 1.50
0.01
7.1.7. Charge efficiency factor
The “Charge Efficiency Factor” compensates for the capacity (Ah) losses during charging. A setting of 100% means that there are
no losses.
A charge efficiency of 95% means that 10Ah must be transferred to the battery to get 9.5Ah actually stored in the battery. The
charge efficiency of a battery depends on battery type, age and usage. The battery monitor takes this phenomenon into account
with the charge efficiency factor.
Default setting
Range
Step size
95%
50 - 100%
1%
The charge efficiency of a lead acid battery is almost 100% as long as no gas generation takes place. Gassing means that part of
the charge current is not transformed into chemical energy, which is stored in the plates of the battery, but is used to decompose
water into oxygen and hydrogen gas (highly explosive!). The energy stored in the plates can be retrieved during the next
discharge, whereas the energy used to decompose water is lost. Gassing can easily be observed in flooded batteries. Please
note that the ‘oxygen only’ end of the charge phase of sealed (VRLA) gel and AGM batteries also results in a reduced charge
efficiency.
7.1.8. Current threshold
When the current measured falls below the “Current threshold” value it will be considered zero. The “Current threshold” is used to
cancel out very small currents that can negatively affect the long-term state of charge readout in noisy environments. For
example, if the actual long-term current is 0.0A and, due to injected noise or small offsets, the battery monitor measures 0.05A
the batery monitor might, in the long term, incorrectly indicate that the battery is empty or will need to be recharged. When the
current threshold in this example is set to 0.1A, the battery monitor calculates with 0.0A so that errors are eliminated.
A value of 0.0A disables this function.
Default setting
Range
Step size
0.10 A
0.00 - 2.00 A
0.01 A
7.1.9. Time-to-go averaging period
The time-to-go averaging period specifies the time window (in minutes) that the moving averaging filter works. A value of 0
disables the filter and gives an instantaneous (real-time) readout. However, the displayed “Time remaining” value may fluctuate
Manual - SmartShunt
Page 19
All features and settings
