I am trying to sort out a mystery in charging displays in my marine DIY system. Here’s my setup:
- I have four 12V batteries, each made with the 280AH EVE cells. Each battery has it’s own 4S BMS.
- The four 12V batteries are connected in a 2S2P arrangement, that is, each pair is connected in series for 24V, and the pairs are connected in parallel for 24V/560AH.
- The batteries are connected to a Growatt 24V 3000A “all-in-one”. I have shore power charging and solar charging. A Victron Smart Shunt monitors the charging as well as the Growatt inverter output.
The issue, maybe simply explained, is that the Victron Smart Shunt always displays about 2X the amperage in or out of the batteries compared to the individual BMS display. Not exactly 2X, but in the ballpark. For example, today I used the batteries through the inverter to run the microwave…the Victron Smart Shunt displayed 44A (which seems high for a microwave), but each of the four BMS units displayed about 26A.
Is this wrong, or what am I missing?
Allan
- I have four 12V batteries, each made with the 280AH EVE cells. Each battery has it’s own 4S BMS.
- The four 12V batteries are connected in a 2S2P arrangement, that is, each pair is connected in series for 24V, and the pairs are connected in parallel for 24V/560AH.
- The batteries are connected to a Growatt 24V 3000A “all-in-one”. I have shore power charging and solar charging. A Victron Smart Shunt monitors the charging as well as the Growatt inverter output.
The issue, maybe simply explained, is that the Victron Smart Shunt always displays about 2X the amperage in or out of the batteries compared to the individual BMS display. Not exactly 2X, but in the ballpark. For example, today I used the batteries through the inverter to run the microwave…the Victron Smart Shunt displayed 44A (which seems high for a microwave), but each of the four BMS units displayed about 26A.
Is this wrong, or what am I missing?
Allan