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5.2
E
NERGY MODE
After pressing the circle in Energy mode the energy harvest is graphically displayed over the last 30 days.
So you can see easily how much energy (Ah) the charging source supplied to your battery system.
5.3
T
ERMS AND DEFINITIONS
Nominal (or rated) capacity
To obtain a reasonable accuracy of the remaining time (see section 5.1) as well as the percentage charge display, the
capacity of the battery to be monitored must be set. Please note that the nominal capacity of the battery should only be
adjusted when the batteries are 100% charged : the capacity indicator is set to 100% and all internal statistics are reset. A
long press on nominal capacity field until BEEP sound allows the reset of the capacity to 100%.
Alarm capacity
A message appears on the monitor to charge the battery (battery circle appears orange) when the battery falls below the
set capacity threshold. The alarm capacity alarm is preset to 50 %. For an average application, this value is usually suitable ;
however, the alarm can be set according to the requirements of the application.
Charge efficiency factor (CEF)
Each battery has a
charge efficiency
. The CEF is the ratio between the Ampere hours that are withdrawn (discharge) and
the Amperes hours required (charge) to recover its original state of charge. This means that more amp hours must be
charged into the battery than can be withdrawn. The efficiency of a lead battery is between 80% and 98%. If the CEF
deteriorates below 75% during operation, this basically means that the battery has reached the end of its service life and
needs to be replaced. The factory default is 98%. The CEF is automatically adjusted by battery management averaging over
the last 4 cycles.
Cycle depth
The cycle depth indicates by which percent value (%) a battery must be discharged and charged so that a charge cycle is
counted. For starter batteries, the value should be between 10-20% and for GEL batteries up to 50 %.
Peukert factor (or exponent)
The capacity of lead-acid batteries is usually stated for a 20-hour discharge. This means, for example, that a 100 amp-hour
battery can deliver 5 amps for 20 hours before the battery runs out. If the discharge current is higher, for example 10
amperes, then the battery is unable to supply the full 100 ampere hours. In this case, the battery voltage drops below the
lower limit of 10.8V for 12V batteries before the battery has delivered its rated capacity.
This relationship can be mathematically determined with the Peukert equation. This equation is used to adjust the
remaining time (see section 5.1) at high discharge rates. Under normal circumstances, the Peukert exponent does not need
be changed. Usually, for lead batteries, unless different values are available, the Peukert exponent is set to 1.27, for lithium
systems to 1.02.
Remaining time
The remaining time is the time during which the main battery can still be used with the current power consumption until
the capacity alarm is reached. During charging, the estimated charging time is displayed until the batteries are about 95%
charged. The maximum value during a discharge process is 99.9 hours (> 4 days). The remaining time is automatically
corrected taking into account the Peukert function.