Charging - Bulk, Absorption and Float

Hi All

Can someone help validate / correct my understanding on the above.

I am trying to understand in simple terms what is happening in these states of charge. I have read Energy Unlimited - and other documents - I think I've got my head around it - but fear I haven't understood it correctly. Be gentle with me if I am being stupid :-).

Bulk -

The charger throws amps in to the battery - as many as it can (while being limited by any specific limits set in the charger). As loads of amps pile in to the battery - the battery voltage rises. When the battery voltage reaches the specified absorption V - bulk stops - and absorption starts. This phase will simply go on as long as it takes - to get to the battery V to the set absorption V. This could take 1 minute, 1 hours, 3 hours....

Absorption -

The charger continues to throw amps at the battery - but in this phase it doesn't allow the voltage to go above the specified absorption V. So, as time goes on, in this phase, the number of Amps drop off, as the battery gets fuller, the charger requires less amps to maintain the battery at the specified V. Eventually the number of Amps being thrown at the battery drops to almost nothing - to hold the battery at the specified absorption V. At this stage, or, when hitting the time limit set for absorption, the charge stops absorption and switches to float. This phase will go on for as long as it takes, or, for a specified time if time limited in settings of any given charger.

Float -

The charger now just holds the battery at a lower specified voltage - trickling the lowest number of Amps in to the battery that it can- to maintain the float Voltage.

Feedback please - am I way off the mark ?



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stevecounsell asked
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2 Answers

Keine Einspeisung in Netz erlaubt.


wie kann ich die Einspeisung verhindern am AC In bei einem MultiPlus2 bei


Da in Deutschland keine Einspeisung auch die 0 Watt Einspeisung ohne Genehmigung

des Netzbetreibers nicht erlaubt ist.

Hub4 funktioniert auch nicht ohne Einspeisung und HUB1 ist wegen der

Spannungssteuerung keine Alternative.

Meine Anlage ist DC verbunden.

- 2 Mppt Laderegler

- 1 MulitPlus-II 48/3000/35-32

- 3 Pylontech US2000

- Venus GX

- ET340

Wozu gibt es im Multiplus bei Grid Code - Settings die Einstellung

-> Use Aux1 as disable FeedIn signal.

Freue mich auf eine Antwort.

knut asked
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mal-l edited ·

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