kimmo-paukku avatar image

Multiplus 48/5000VA overload scenario.

Hello Sirs,

I have a question regarding Multiplus 48/5000VA possible overload scenario.

My Multiplus should hande around 4500W continuous load, right. My hole house is behind this inverter, but I also have 16A grid connected to Multiplus, just in case.

My house is pretty small, so normally there is no problems to run the hole house with inverter and solar panels.

Now I have a plan install few heaters (Winter is coming)….

My question is:

If Multiplus output power is on the limit, let say close to 4500W, 16A grid is connected, and ESS is running with 20W grid setpoint, does Multiplus draw automatically from the grid more power, if total load goes over that 4500W limit …. Let say like close to 5000-5500 W ?

All load is connected to AC out 1, AC out 2 is not in use, and I want to keep it that way.

I have never tested overload scenario…. So that’s why my question…


MultiPlus Quattro Inverter Charger
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I think one thing missing from the Victron system is a load shedding/management system. Quatro have two AC outputs BUT the "non-critical load" output is switched off when the grid switches off even if there is power available from the inverter.

A more versatile approach would be to disconnect the non-critical loads only if there is a risk of overload.

A better solution yet would be to have multiple AC outputs (maybe via external contractors) with each one having a different priority. Lower priority loads would be disconnected until a pending inverter overload is addressed.

Most whole home generator systems have load management as standard or an option. They generally shed loads only AFTER an overload exists. I built one for my portable generator that won't switch on loads unless enough available power is available (I tell the system how much power a device is expected to use.)

I wouldn't expect Victron to incorporate the necessary logic into its Inverters or into the GX control system. But an external control system would be valuable to many.

The continuous max output at 25 degree C is actually 4000W and even less at higher temperatures. Small but important detail. Also, have you maybe considered hooking it up parallel and not use ACOUT or do you use it as a backup system regularly?

Thanks for your answer.

I have cooling fans, and also small Air. Con. unit in my Victron "cabinet", so temperature is not the problem. Cabinet temperature is around +22 C.

No......, its better to have all behind the inverter, so I don´t need any external kWh meters for monitoring my system :)

I like to see monitor my system with VRM/Grafana.

Attention - At cabinet temperature of 22c the multiplus itself has more than 25c for sure ! So the Multiplus will not reach 4000w continuously.
My Multiplus 3000 manage to hold 2000w (instead of 2400) at 23c cabinet temperature.

1 Answer
Daniël Boekel (Victron Energy Staff) avatar image
Daniël Boekel (Victron Energy Staff) answered ·

Hi @Kimmo Paukku

Yes it will draw the rest from the grid.

an issue to avoid is:

-when battery is empty, and more power is used than the 16A grid connection can supply, the inverter cannot assist and everything will be drawn from the grid, so possibly overloading your grid supply.

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Hi Daniel,

Thanks for your answer.

Yep, that I was thinking as well.

I use GX generator start/stop relay several conditions for driving external AC relay for let AC in to Multiplus. I my case, I never draw batteries to "empty", so there is always some "buffer". In emergency case, with ESS grid setpoint (+ 1000-1500W) I can also draw some extra power from grid, if needed.

I also use Multiplus K1 relay for driving external AC relay for drop heating/cooling circuit off, if there would be a biggg overload situation.

As I said, my house is very small, and this setup works just great :)

Thanks again for your help ! :)