When I look at the Minimum Shore Current Limits 07-2019 xls file, it states: There will be no minimal limit when PowerAssist function is disabled. I do not anticipate needing PowerAssist's magic, so if I turn off PowerAssist, can I set the minimum charge current limit to 5A on my 12/2000/80 115v Multi or does it mean I am unable to set a minimum limit when PowerAssist is off?
Since I got the Shore Current Limit file from a link on one your answers, would you @Guy Stewart (Victron Community Manager), mind taking a look at this. I am having a lot of trouble getting a Min Current Value of 5Amps to work.
Thanks much!
Hi @VanMan,
The reason for the PowerAssist AC input current limitations are due to the precision of the AC input current detection. So we allow reduced settings when PowerAssist is disabled, but that doesn't mean it will behave like you want it to at very low current limits.
If you have disabled PowerAssist, the only load on the AC input supply should either be pass through (which you will need to control yourself by limiting your loads to the capacity of your AC supply) OR the Multi itself using the AC input to charge the battery with DC.
There is nothing we can do about you overloading your generator or shore supply by connecting too many loads to the AC output of the Multi when shore or generator is connected. I would suggest an easily resettable circuit breaker on the AC input supply JUST before the Multi that is sized to your known current limit. That way even if you trip it, it's easy to correct.
However what we CAN do something about is how much current the MultiPlus itself pulls to charge the DC batteries. This is a different setting in VE.Configure - Charge Current in the Charger Tab -
https://docs.victronenergy.com/veconfigure.html#charger-settings
Reduce this Charge Current figure until your AC input supply is no longer overloaded (i.e 4 Aac @ 115v ac = 38Adc @ 12Vdc), and adjust further downward from there till the problems stop.
Note that this will be a combined factor if you are ALSO running AC loads at the same time as charging batteries, you could still overload the AC input with AC output loads + DC charger (and this is one of the problems that PowerAssist was invented to solve).
Finally, 5A is a tiny supply (or very small generator?) - if you have even less than that available, it might just be that you need to do something instead to increase capacity at that point to get the results you want.
Thank you @Guy Stewart (Victron Community Manager) this helps a lot. A bit more about my system:
I have a 100/30 SmartSolar MPPT with 335w panel. Typically solar keeps 200Ah batteries in good shape. However in winter and cloudy days I need to top off solar charging with an alternator powered Phoenix 800 to Multi. Yes, the AC charger route is inefficient, but the AC wiring from front to rear of van is a real plus. Having everything including SmartShunt on VEConnect is great. VenusGX to VRM is so cool.
When using Phoenix to charge, I never have ac load and also low dc loads, so either of your scenarios above will work fine. I will only need a couple hours charging every days or so (in winter).
The current breaker is 8A so I will change it to 5 just to keep things at desired loads vs max loads ... good idea.
Any other settings you can think i need to be looking at.
On another note, Id like to discuss work i am planning for a Car Play app for other Van users who wold like to have van display in addition to VE Connect.
Again thanks much and your videos have been very helpful too.
Thanks @Guy Stewart (Victron Community Manager)!
Is the Charge Current the amount to current leaving the Multi or the amount of current into the batteries. For example:
Charger Only
Charge Current set for 50A
25A from Solar
5 A DC load
What is theoretical (100% efficiency) AC-in current?
In other words is the Charger Current changing as solar (and other loads) goes up and down or will the current to the battery be changing and the Charger Current remains (relatively) constant?
I can accommodate either scenario, but would like to better understand before setting up.
Also, if Charger Only and Power Assist off and Shore Limit AC-in set to 5 amps (Shore Limit I would expect DC to look like this:
44 A from multi (5*115/13)
25 A from Solar
-5 A DC Load
64 A to battery
In this mode, seems like the DC to battery would move up and down as solar changes?
Anything else I should be looking at here? Thanks again
