We have 20 AGM 330ah linked in strings of 4. We had a single MPPT 150 100 TR which was preconfigured by the installer with a single array of 5.5kw. Linked to a Venus GX via VE direct cable. We have now added another MPPT’ 150 100 TR VE Can and another separate array 5.2kw pf panels. The new MPPT has been linked via VE direct cable to the Venus.
To coordinate the charging of the battery system, I have enabled DVCC. Enabled Limit charge current to 100A. Enabled Manage battery charge voltage to 54.4V SVS is enabled, STS is enabled. I don’t know if these two figures are correct and want to ensure no damage can occur to the storage system. So my questions are Is the charge limit correct, if not what should it be? Is the the manage battery charge voltage correct, if not what should it be?
I assume you mean 12V AGM batteries so you have 5 parallel strings of 4 batteries in series for 48V nomimal at 1650Ah.
The limit charge current at 100A, I would have thought good AGMs can take at least 0.1C so 165A, possibly the full 200A, check your battery datasheet or manufacturer info.
Limit charged voltage does not work for lead acid / AGM batteries, it only works for managed batteries, i.e. lithium batteries where the BMS manages the charging.
The charging is controlled by the individual MPPT, make sure all settings for absorption, float, temperature compensation on the new MPPT match the ones on the old MPPT.
Thank you for your reply. Yes the battery configuration is 4 batteries each on a string and there are 5 strings.
I had a look at the battery data sheet but not much is making sense there. I will contact the manufacturer to confirm with them.
Do I just turn off the limit charge voltage? I am assuming so from your comment.
How do I find the information about how to set the MPPT to that of the old MPPT? I am using the victron app and cannot find these settings under the actual MPPT’s.
I found the settings under the device list via Victron Connect. Both have the same settings. The new one is acting as a slave the old one is controlling the slave. I think that means I don’t have to take any further action. Thanks once again for your help.