question

raymiller avatar image
raymiller asked

MultiPlus II - Conditional AC connection - AC input connect on load - Connect when load is higher than_not working reliable

During commissioning testing of MultiPlus II 24/3000 Firmware 481. My MultiPlus II has been set to: Conditional AC connection (enabled)- AC input connect on Load (enabled)- no battery condition is set.

The unit exhibits a problem that fails frequently to switch to Passthu mode when the "connect when load is higher than xxW" condition is True.

I've set the lower power limit to 69W and upper 81W for this test to be within the limits of my testing equipment. The grid is stable both in voltage and frequency during the test.

conditiona-ac-input-connection.png

What happens is: (when the load power level exceeds the upper power threshold of 81W)

- the Inverter output syncs to Grid immediately (monitoring dual trace CRO on Inverter and Grid)

- relays go through test condition (as when first the Grid is present)

- after a time period (about a minute at least) the Grid loses sync with the Inverter (briefly 1-2 seconds) and relays go in test condition again

-intermittently (and after a variable time) the MultiPlus II correctly goes into Passthru mode

- each time when the lower Power limit W is reached it correctly goes to "Inverting" mode with "AC input disconnected" (which is what I expect to happen).


I've tested the islanding function, Conditional AC connection - the battery voltage setpoints, connect and disconnect. These pass the commissioning test.


A couple of issues arise.

When the load exceeds the upper Conditional AC power limit, the MultiPlus logic programming has a problem consistently activating the Passthu mode.

I need this Conditional AC power limit mode to operate my ESS to mainly operate in off-grid mode, but need the grid to reliably back up the ESS during brief periods of high loads.

Victon Connect only displays limited information about the logic conditions which are triggered. i.e. no display that shows what logic condition has been triggered "Conditional AC connection- AC power <> than setpoint or battery voltage limit etc. Having more information regarding the logic conditions would be invaluable in tracking down both human error with programming and any faults with the energy system.


Also discovered a spelling error in the English message of the Viction Connect display, which should read "Grid disconnect reason".

I hope I've detailed the problem I'm experiencing in a clear manner and look forward to an update that fixes the problem.

Regards From Australia

victron-connect-spelling.png


Multiplus-II
2 |3000

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1 Answer
jurjenhoekstra avatar image
jurjenhoekstra answered ·

Hello @RayMiller, did you ever solve your problem. I experience the same issue with a quattro.

2 |3000

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