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Bruce Orr avatar image
Bruce Orr asked

Single charge controller exceeds network output?

I have 3 250/100 charge controllers with a BMV-712 all networked together. Usually the network total power is roughly 3 times each charge controller. But today I saw the network total power was much less than the output of one of the controllers. How is this possible? See screenshot.


screenshot-20220112-093731.jpgOther observations:

1. With no load, controllers are putting excessive current into batteries while in Absorption.

2. Looking at the shunt, the current going to the batteries is way over the charge limit I set in the controllers.

MPPT Controllers
screenshot-20220112-093731.jpg (188.9 KiB)
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snoobler avatar image
snoobler answered ·

Was the charging in absorption mode when you saw low power? If so, that's normal.


The current limit is for EACH controller. The limit is not shared by all controllers. The only way to limit total charging from multiple devices is via the GX DVCC function.


https://www.victronenergy.com/upload/documents/Manual-VE.Smart-Networking-EN.pdf

Page 3:

"Each unit will (and should) regulate its own output current. Which, among others, depends on the output of each PV array, cable resistance and the configured maximum output current of the charger. As such, it is not possible to configure a 'network-wide' maximum charge current. In case such feature is needed, for example in a system with both an East- and a West-facing PV array and relatively small battery bank, consider using a GX Device and its DVCC features."


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Bruce Orr avatar image Bruce Orr commented ·
Thankyou, I had assumed the current limit was for the network. Still confused by the single controller producing more watts than the network total power shown in the screenshot.
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snoobler avatar image snoobler Bruce Orr commented ·

I didn't understand your initial concern, but I can see the discrepancy on the display.


This might be pertinent:


https://community.victronenergy.com/questions/81820/victron-connect-showing-wrong-total-network-power.html


and


https://community.victronenergy.com/questions/86051/smartsolar-update-v156-killed-network-power-total.html

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