Function Overview - Victron energy BMV-600S Manuel

3.4

Function overview

The BMV factory settings are suitable for an average lead acid battery
system of 200 Ah. The BMV can automatically detect the nominal
voltage of the battery system (see section 2.5.3), so in most cases the
only setting which will need to be changed is the battery capacity (Cb).
When using other battery types ensure that all the relevant
specifications are known before changing the BMV parameters.
3.4.1 Setup parameter overview
Battery capacity Ah. The battery capacity for a 20 h discharge rate at 20° C.
Cb:
Vc: Charged voltage. The battery voltage must be above this voltage level to consider
the battery as fully charged. Make sure the charged-voltage-parameter is always
slightly below the voltage at which the charger finishes charging the battery (usually
0.2 V or 0.3 V below the 'float' stage voltage of the charger).
It: Tail current. When the charged current value is below this percentage of the battery
capacity (Cb), the battery can be considered as fully charged. Make sure this is
always greater than the minimum current at which the charger maintains the battery,
or stops charging.
Tcd: Charged detection time. This is the time the charged-parameters (It and Vc) must
be met, in order for the battery to be considered fully charged.
CEF: Charge Efficiency Factor. The Charge Efficiency Factor compensates for the Ah
losses during charging. 100 % means no loss.
PC: Peukert exponent (see chapter 4.3.4). When unknown it is recommended to keep
this value at 1.25 for lead acid batteries and 1.15 for Li-ion batteries. A value of 1.00
disables the Peukert compensation.
Ith: Current threshold. When the current measured falls below this value it will be
considered as zero Amps. With this function it is possible to cancel out very small
currents that can negatively affect long term state-of-charge readout in noisy
environments. For example if an actual long term current is +0.05 A and due to
injected noise or small offsets the battery monitor measures -0.05 A, in the long term
the BMV can incorrectly indicate that the battery needs recharging. When in this
case Ith is set to 0.1, the BMV calculates with 0.0 A so that errors are eliminated. A
value of 0.0 disables this function.
Tdt: Average time-to-go. Specifies the time window (in minutes) that the moving
averaging filter works with. Selecting the right time depends on your installation. A
value of 0 disables the filter and gives you instantaneous (real-time) readout;
however the displayed values may fluctuate heavily. Selecting the highest time
(12 minutes) ensures that only long term load fluctuations are included in the time-
to-go calculations.
DF: Discharge floor. When the state-of-charge percentage has fallen below this value,
the alarm relay will be activated. The time-to-go calculation is also linked to this
value. It is recommended to keep this value at around 50.0 % for lead-acid batteries.
ClS: Clear SOC relay. When the state-of-charge percentage has risen above this value,
the alarm relay will be de-activated. This value needs to be greater than DF. When
the value is equal to DF the relay the state-of-charge percentage will not activate the
alarm relay.
10