115v watermaker on inverter?

[crayiii]

I'm having 600 AH lithium (Relion HP) batteries installed. The spec says that they have a Max continuous discharge date of 100 amps each and a peak of 800 each for 2 seconds. I'll have two batteries so my understanding is that the discharge rates are added together for the bank.

Also being installed is a Victron Multiplus 3000 charger/inverter.

I have a Sea Recovery 700-1 115v watermaker that I would love to be able to run from the inverter sometimes if possible.

The manual shows two motors for the unit. A 3hp pressure pump that has 25.4 full load amps and a locked rotor amperes value of 86 for startup. The second motor is a 0.5hp booster pump with 9.4 full load amps and 20 locked rotor amps for startup.

Can this unit be run from the inverter as is? Can anything be modified to allow it to be run? Is either are true, is it worth it or will the batteries die too fast?

We have 900 watts of solor and 800 watts of wind.

We're trying to find a way to not rely on the generator so much.

[Sailmonkey]

3000 watt inverter @ 115 volts is 26 amps.

3000 watts at 12 volts is 250 amps.

I don’t think you’re going to be running your watermaker from your inverter.

[john61ct]

Originally Posted by crayiii

will the batteries die too fast?

You would need a huge bank to feed that much power so many minutes.

So in practice, no, an ICE charge source must be running basically concurrently with the WM.

Going to a much slower (gallons per hour) but more efficient (gallons per bank Ah) WM like the Spectra would be better for a mostly-solar setup.

[crayiii]

This is what I expected to hear. We really want to reduce our reliance on the generator as much as possible and this watermaker only has 125 hours on it but I'm thinking about making a swap.

Now I just need to find a DC watermaker that can utilize as much of what I already have as possible.

[eheffa]

I went through this recently with my newly installed (used) AC watermaker; a village Marine 600 which draws 12 Amps AC while running. I have 550 W of solar and a 160A alternator serving a 660 AH (Firefly Carbon Foam) House bank. We also have a 9 KW Onan Generator so do not lack AC power generation. I do not like to run the generator any more than necessary though. In our cruising grounds of the BC coast, sunshine can be limited, especially in the winter months.

Recognizing that this 12 Amp AC current translates into about 100A at 12 VDC I thought I could at least run the watermaker off the inverter while underway. (I would not try to run it off battery power alone.) As it has turned out my inverter (a Magnum MS2812) while easily capable of handling the 12A running current, cannot tolerate the brief startup surge of > 80A.

As I've thought more about though, the draw of ~100 A DC along with potential charging demands, say starting off in the morning after night at anchor, would represent a fair bit of load and wear and tear on the engine alternator.

While at anchor, we commonly run the generator for re-charging the House Bank for ~ 2 hours. In that time, we can easily make 35 USG of fresh water. If we need to make water while underway, we just need to use the generator.

I have abandoned attempts to get a soft start etc. to make it work under DC.

-evan

[eheffa]

Oops. Double post

[CDR Smith]

I think this one of those instances where what you want is a unicorn. If you want that watermaker, you're going to have to run your generator.

[warrior 90]

Originally Posted by crayiii

I'm having 600 AH lithium (Relion HP) batteries installed. The spec says that they have a Max continuous discharge date of 100 amps each and a peak of 800 each for 2 seconds. I'll have two batteries so my understanding is that the discharge rates are added together for the bank.

Also being installed is a Victron Multiplus 3000 charger/inverter.



We have 900 watts of solor and 800 watts of wind.


We're trying to find a way to not rely on the generator so much.

I read Your inverter has a peak capacity of 6000 W
https://www.victronenergy.com/upload...120V-US-EN.pdf

Because solar and wind are a variable I would not recommend to include it for calculating.

First I would perform a real time test in generator mode to analyse true values.

What is the capacity of Your generator ?

[crayiii]

Originally Posted by warrior 90

I read Your inverter has a peak capacity of 6000 W
https://www.victronenergy.com/upload...120V-US-EN.pdf

Because solar and wind are a variable I would not recommend to include it for calculating.

First I would perform a real time test in generator mode to analyse true values.

What is the capacity of Your generator ?

It's 8.5kw for the generator. When I start the watermaker, I only see an increase of about 22amps on the generator panel. I'm not sure how sensitive the panel readout is to instantaneous surges though.

I was also looking at having the inverter power the watermaker at all times so it would do the auto flush and then just remember to not push the start button unless the generator was running.

The issue I see there is if the generator or shore power tripped for some reason it would overload the inverter if the watermaker was running.

[jclark500]

I had a switch installed to run watermaker from inverter when engine is running.
Not totally what you were looking for, but seemed silly to have to run the generator while motor sailing. Just have to be careful to not run anything else, and I mean anything off the inverter.

[john61ct]

Originally Posted by eheffa

While at anchor, we commonly run the generator for re-charging the House Bank for ~ 2 hours. In that time, we can easily make 35 USG of fresh water

If you're running ICE power anyway, high gph is the way to go

> would represent a fair bit of load and wear and tear on the engine alternator.

It's engine wear that adds up, alt NBD I would use whatever ICE sources are running anyway to top up the water tanks

[alansmith]

I think Rich Boren’s Company of using s high output watermaker and the Honda 2000 is a smart move for guys like me. I have an outboard so can’t rely on diesel generators. Honda is highly reliable and cheap compared to diesel generators. I don’t worry about gas because I keep everything above deck. Haven’t pulled the trigger yet on purchase but it makes the most sense to me.

[bradfordharley]

We have the cruise RO SM30 and we run it off the inverter all the time. I specifically installed a second alternator (2x125a) to do this. It allows us to make water any time we motor, and the motor likes the extra load. It runs fine off our 2500w inverter.
From your specs, you have a 3hp a/c motor. We have a 1hp motor. Our system pulls about 70a @12v while running for the boost and HP pump and works flawlessly. I cannot imagine even a 3000w inverter supporting a 3 HP pump, and scratch my head why it’s so big.... how many GPH do you produce?
We also run a Honda 2200 when at anchor to make water.
It’s all about trade off’s, and the cruise RO doesn’t fit all needs, but we are happy with it for a size/production and utility perspective. I personally like our setup vs a 12v system.

[warrior 90]

Originally Posted by crayiii

It's 8.5kw for the generator. When I start the watermaker, I only see an increase of about 22amps on the generator panel. I'm not sure how sensitive the panel readout is to instantaneous surges though.

I was also looking at having the inverter power the watermaker at all times so it would do the auto flush and then just remember to not push the start button unless the generator was running.

The issue I see there is if the generator or shore power tripped for some reason it would overload the inverter if the watermaker was running.

When walking at the limits forget the cheap meter on the panel. Use a decent clamp meter to get accurate values of surge and current draws.

A posible solution I could think of is just adding another extra and cheap inverter with enough capacity as an independent circuit directly from the batteries. Anyhow I would not like to push the limits with my expensive Victron that I rely on for many other equipment. As long as Your batteries can handle it now together with the gen You would have two sources of energy for making water. You put Your Gen in automatic start when the battery gets low to be safe in case Your wind and solar are short and You have all the water You want. You run Your system very efficient while OFF main engine and shore power.
Anybody correct me.... is there any reason that I need an expensive "PURE SINE WAVE" inverter for a watermaker ?

[john61ct]

Originally Posted by bradfordharley

We have the cruise RO SM30 and we run it off the inverter all the time.

Yes running off a powerful enough inverter is not a challenge, as long as an ICE power source is feeding the amps required.

It's running a high gph unit off the bank **stored** energy that is impractical for most, i.e. without ICE running, or even a mostly-solar setup.