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Neil avatar image
Neil asked

Grid and AC loads being combined to give power consumption

It would appear that the power consumption from the grid is being added to the AC loads to give the total KWh consumed, I find this very strange as we have a 12v system too, but when we have been trying to work out our monthly power consumption, we have no idea what it is. obviously the grid power and AC loads will be different as some power from the grid is diverted to power the 12v system and charge the batteries, but I can’t understand why the Grid and AC loads are combined to give a total consumption? Makes no sense at all, as the result would be completely inaccurate. We can see our Grid supply is around 500w and ac loads around 420w (fridge and heating running on 12v) but then the two are combined showing we are using 920w, bur we are now using 920w just 500w, then at the end of the day/week/month it gives a wholly inaccurate reading showing in the region of 500kwh,

is there a way to separate these consumption figures again?

Multiplus-IIcerbo gx
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Jason - UK avatar image
Jason - UK answered ·

@Neil Electric water heaters can be heavy on the the electrical loads. With a base load of 500w, thats 12kWh per day on its own. A 1.5kW water heater coming on for 10 minutes in every hour is another 3kWh per day at least. That's 15kWh per day. Then you also appear to have another load on your consumption with a modulating demand, Do you have a fridge or some sort of a electrical heater with a stepped increase in demand? It could be a battery charger which would match the variable loads other than the base load and the water heater. American equipment is not famed for its efficiency.

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Jason - UK avatar image
Jason - UK answered ·

@Neil Could you provide more information on your set up please? A schematic of your system would be ideal should the location of your CT sensors (if any), and also how your system is set up. Im assuming you are set up for ESS? Setting form EV config, Screen shot of VRM would also be helpful when the issue is apparent.

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Neil avatar image
Neil answered ·

@Jason - UK

thanks for replying,

link to my VRM share https://vrm.victronenergy.com/installation/107032/share/cd72773c

this installation is in an American 5th, based in the UK.

we don’t have any CT’s.
we have;

2 x 200ah renogy lithium batteries,

Victron smart shunt 500A

victron distributer,

Victron multiplus II, 12v 2000/80/32

Victron 150/85 TR solar charge controller.

Cerbo GX and various temperature and tank sensors.

sorry, the image showing the installed system was thrown together for our own purpose, never had chance to update it.


ESS is not enabled, we generally only have electric hookup in the colder months, during summer we rely solely on solar power, and a generator if required.

Any assistance is great fully received.

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Jason - UK avatar image Jason - UK commented ·

@Neil 500w'ish appears to be your base load but you are having peaks of between 1500w and 2000w so the 1kWh over the last hour appears to be correct.

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Neil avatar image
Neil answered ·

@Jason - UK

it seems to be correct at times, but it has also shown we have used 30kw on days when we have only had a light on and our diesel heating, I have bought another electricity meter now which I want to get fitted in the next couple of weeks. Hopefully get a comparison across the two meters then.
the water heater is 1500w and it runs every hour ish for 10 minutes.
the base load is a couple of tube heaters and running the victron system.

if we are really using the amount of electric the Victron system says, we need to change the water heater as this is quite shocking.

thanks for your input, much appreciated.



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Neil avatar image
Neil answered ·

@Jason - UK

we have a 12v compressor type fridge, it runs for about 10 minutes every hour, draws about 8a.

a 240v fan heater that is only used at night while we sleep, set at 12 degrees c.

a laptop I use for work.

the usual phone chargers etc.


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