Incorrect AC input reading on Cerbo

Q&A and troubleshooting
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1

We have installed a Victron system upgrade utilizing 3 Multipluss II in parallel with a Cerbo MKII and other associated components.

Our issue is the system takes in 30A or more when commanded to restrict the input limit to 28A. This is verified in the photos attached. You can see each leg adds up to around 23A into the inverters and the system only sees 21A input as shown on the laptop. This has been verified on each inverter input line as well as on the line in before and after the ELCI, and the line to the junction box where the line is split into 3, one for each inverter. No matter what settings we select for the AC input it is always reading about 2A lower than actual input. This is a problem given we can only reduce the 3 parallel inverters down to 28A and we are on a 30A shorepower cord.

We have checked multiple locations with different multimeters. We have checked for loose terminals and bad connections.

Is there a setting we can adjust in the cerbo to make the detected AC input better represent the actual AC input?

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2

The mp has a problem calculating the input current with inductive loads.

This problem was solved in v522.

3

We did update to 522 however that did not solve our problem. The master would read lower than the two slave units when we were having the issue. We re-mapped the MP units making one of the slaves the new master. This has solved the problem. We are still about .5-1A higher actual amperage than what the system indicates but this allows us to still remain below the 30A circuit breaker limit with the error.

Hope this helps someone else.