Victron Multiplus

[recurveman]

Hi,

I purchased my boat with 2400ah or lithium batteries and (3) 3000 watt Victron Multiplus inverters. Only problem is I really don't need 9000 watts of inverters. I really only need 3000 watts of inverters and would like to take 2 of the inverters off line. I live on the hook and I would like to reduce power consumption so I don't need to run the generator as much. How do I take one or two of the inverters off line?

We are currently in the USVI and moving to the BVI then St Marteen.

Thanks,

Chad

[CrispyCringle]

There is not enough info to properly answer your question. There are several ways the inverters could be wired up. You need to figure out where the AC output is going for each inverter. Also where the DC connections go. Thats how I would start.

You've got a huge amount of electricity on board.

[CarlF]

Most likely your multi’s are set up to work together. You will need to download some free software (VEcomfigure) to a laptop and then connect the laptop to the multi with a USB dongle.

It’s best to hire someone who done this before

https://www.victronenergy.com/suppor...e-bus-products

[smac999]

You are going to have to program the remaining one as a single master. Otherwise it will just error if it doesn’t see the other 2.

If it’s in 3 phase you are going to have to figure out how to redo it all. Hopefully they are just in Parellel.

You may not need 9000w of inverter but you probably want all the charging from them.. at 100a with 1 multi it would take 24 hours to charge that bank from a gen. Instead of 8h hours with 3 of them charging. Removing them will add gen time not reduce it.

[SailingHarmonie]

If your objective is to minimize generator run time, keep them. Removing two will reduce your charging rate by 2/3, greatly INCREASING generator time. The idle current from the unused inverter capacity is not large, and will have a minimal impact on your power budget.

[SailFastTri]

If you only want to reduce idle power draw, can you power off the extra 2 inverters through software via the display panel?

[smac999]

Originally Posted by SailFastTri

If you only want to reduce idle power draw, can you power off the extra 2 inverters through software via the display panel?

No. The 3 are simply one big inverter to the screen.

On the first multiplus 20 years ago you can shut off the switch on the slave abd the master still works. Abd half the idle draw. But I’m pretty sure on the newer ones if you shut the slave off the master will freak out.

[Orin]

Have you measured the idle current draw?
As in turn off all your AC breakers and measure the current going from the battery to each of the units?

A lot of people overstate the amount of power devices draw when they’re off or at idle.

I have had Chinese inverters that run the cooling full blast at idle. Which I got rid of because of the noise. These are not those inverters. If it comes back at 35mA at idle or 0.035A are you still concerned?

If you remove 2 inverters will you find yourself in any situation where having the others would have been beneficial?( Such as having high inrush current on a device, expandability for the system, or redundancy)

Also, there’s an “on/off/charge only” switch on the inverter per the manual? Have you tried putting that in the off position?

[smac999]

Originally Posted by Orin

Have you measured the idle current draw?
As in turn off all your AC breakers and measure the current going from the battery to each of the units?

A lot of people overstate the amount of power devices draw when they’re off or at idle.

They are going to be 2-3 amps each. So maybe 9a total. That is a huge idle draw.

The new multiplus ii are better. An amp less each.

The xantrax sw2000 is worse. The 2000w idle is 4a draw.

[LoudMusic]

With that much battery and inverter power I'd be dumping the generator and loading up on solar and maybe a wind turbine. Especially on a 50' catamaran.

[Orin]

Originally Posted by smac999

They are going to be 2-3 amps each. So maybe 9a total. That is a huge idle draw.

The new multiplus ii are better. An amp less each.

The xantrax sw2000 is worse. The 2000w idle is 4a draw.

That’s surprisingly high!

a 2400Ah even at a conservative .3C (lead acid range) charge rate it’s still accepting up to 720A of charging. You’d have to have incredibly spaced out charging rate before it made sense to get rid of those chargers.. provided your generator is 9kVA or more. I guess if you run your generator on average less than half an hour a day. (Not considering the 72Ah removed per inverter/day). It would make sense to eliminate them. That said if I used that little amount of power I would put a switch on my inverters and turn them all off if I wasn’t using them.

[mlydon]

Your biggest advantage with the 3 multi pluses is rapid CHARGE current- ganged, the will put out 360amps, and your lithiums will take it all. As someone already pointed out, this greatly reduces your generator run time, and is the biggest advantage of lithium, to my mind.

Just leave the system in charge-only mode, and only turn on inverter mode when you actually need ac power - draw in charge-only mode is pretty low - while they still draw some, you’re only powering the control boards on the units.

I have a single unit - with all the other “smart” electronics on my boat, I draw approximately .4 amp swinging on the hook. If I leave on the invert mode, it’s more like 2.5 - 3 amps. But why would I do that? I really only need ac to run a toaster, or whatever , for 10 minutes at a time. Things like phone chargers should be 12v to begin with - running 110ac inverted, to run a wall charger which reduces the voltage back to 4 volts dc is incredibly inefficient.

I actually leave the multiples completely OFF, unless I’m using it, one way or the other.

Matt

[Sawbonz]

I guarantee that they were installed for their charging, but with a 50 foot catamaran I'm surprised that you could suffice with 3000 watts of inverter. You should be able to run everything on batteries only, including air conditioners. The cost savings will be negligible.

We have 2 Multiplus in parallel for charging our 1800ah of lithium with the 6kw generator when solar doesn't keep up. We are running the hot water heater all of the time lately and soon will kick on the air conditioners too, all on the inverters. I ran the generator today for 5 hours which averages about 1 hour per day, but only because I can add twice as much power per hour than if I only had one Multiplus. In over 4 years I'm right at 600 hours on the generator. Of course time at the dock or on the hard is not reflected in that time frame.