Inverter for '83 48MY ...

[Buccaneer]

Why these were't standard equipment... OK, so I want to put one in, mainly to service the frig, Sat TV (kids, you know), stereo. I figure to place it under the gally bench seat nearest the engine room bulkhead.

Recommendations on inverter size, location, installation, and anything else I need to think about?

 

[Pascal]

2 to 3KW is a good size, not a huge price difference and it's good to have some reserve.

Get one with build in charger, 3KW units recharge at up to 125 to 150 amps that's much faster than conventional chargers; you want to minimize genny run time.

I have a freedom 30 which works well, although it's not pure sine. No issues with that but there are some true sine waves now that are not that much more expensive.

For wiring you have two options.

- an inverter with built in transfer switches which will automatically come on line when shore/genny is turned off. when power comes back on they switch to charge more.

- no built transfert switch will require manual transfer on the panel, by replacing/adding rotary or dual breakers with safety slide.


Note about transfer switches. Makes sure the inverter has dual 30amps input to ensure you get full pass thru power and full charging. Outback inverters have been installed by a few members but AFAIK they only have one input, so i dont' think you can recharge at max capacity and pull 30amps pass thru at the same time, you will need to use an external transfer switch. Corrections welcome from outback users!

In addition to the Freedom 30, you can also look at the Xantrex MS3000 and also Magnums.

an other issue you may have is voltage. It's been discussed many times before but 32v inverters are harder to find and more expensive. Some prefer using the same house bank, I like using a separate inverter bank. In that case you use a 12v or 24v bank/inverter; obvously you need the room for the extra batteries. But if you're going to use the inverter a lot (exp. for the fridge) you will need extra batteries anyway. I like the redundancy, especially since on many Hatteras one bank is shared by one engine and house duties.

regardless of brand, look for high capacity charger and dual line inputs.

 

[MikeP]

The Outback 3230 is a superb 32V 3KW unit that seems almost tailor-made for our 53MY. Can't imagine a better or more efficient unit. Truly one of the best (maybe THE best) items I have put on the boat. Not cheap though...

http://www.wmjmarine.com/vfx3232m.html

I should have mentioned that when I installed the Outback it required no battery additions to the regular 32V system in order to run the fridge, TV, Stereo, Microwave, assorted items like hair dryer, etc for 18+ hours and those batts would still start the engine. With just the fridge running, the batts/inverter kept it going for two full days while the boat was on the hard getting the bottom painted. The original inverter on the boat (optional, apparently) would run the batts down in a few hours. Efficiency has come a long way!

 

[REBrueckner]

Pascals comments are entirely appropriate; a few additional thoughts: If you use an inverter much larger than needed you'll use additional power, as they are less efficient at low loads. This may or may not be significant depending on how long it's used. For an hour or two daily, its insignificant; for 12 or 15 hours daily it could add up.

Also, if you use a built in charger it may not supplement exisitng chargers used in parallel; it may shut other chargers down or be shut down itself...so you may find you have to charge different banks from different chargers. If your existing charger capacity off your genny is limited, then getting an inverter/charger with more output chargeing amperage is a good move if you need to charge from genny and don't use it much.

Finally, you should get an idea of your peak load (of accessories) for the inverter...that's how you select the size you'll need. You should also check your power consumption between battery charges, that is, your amp hours consumed. If you will run your frig/freezer and other accessories from battery instead of genny, you may have to beef up your battey bank. In general, for daily charges your battery bank should be about three to four times the amp hour load so as not to discharge your batteries too deeply. So, for example, if your daily amp hour load is 150 amps, perhaps typical unless your frig/freezer is big and its 90 degrees, you should size batteries with about 450 to 600 amp hours capacity...or more. That will keep them from discharging more than 50% which shortens life. If you want to run your genny only everyother day, for example, you'll need twice the battery bank capacity.

 

[REBrueckner]

If you want more information on "DC SYSTEM DESIGN", that is sizing your battery bank to meet your accessory load requirements, see my 2005 post under that title here on SAMS.

 

[DCMY #92]

I installed a 12V Xantrex MS3000 and a new 650 AH bank in our 41 a few months ago for the same service you describe. I also installed the networked remote panel and auto generator start. All works great so far and requires no manual intervention.

I don't know how large or well ventilated the mounting location you mention is, but this unit - as any other unit of this power - needs plenty of air flow. You must also limit the distance from the battery bank to keep the cable size reasonable - particularly with lower voltage system.

You may find that you must so some rewiring at the panel to isolate the circuits served by the inverter properly. No matter what unit you select, I suggest you download the installation manual and work out all of these details before you purchase.

 

[Pascal]

Mike

actually it's a pretty good price... the Modified Sine wave Freedom is around $1200 and the MS3000 is around the same price as the outback

maybe you can clarify the input issue... from what i read, the outback has only ONE 30amp input which is shared by the charger and the pass thru circuits, is that correct?

this means that you need to use a manual transfer switch to power your circuits, i think you have a relay on your boat, don't you?

if you dont use an external transfer switch, then you are limited to 30 amps TOTAL while charging... that's an issue. with TWO input lines, you can get 30amps to charge and a full 30 amps pass thru to your loads.

 

[MikeP]

Pascal - I never even looked at the charging side/capability of the unit since I just left all oem charging units in place. So I didn't see any reason to try to hook that up from the inverter. Your point is a good one and whatever that capability is needs to be looked at if you are going to use it.

But if you have existing charging systems for the 32v batts, I can't see why it would be good to connect another one but maybe I'm missing something obvious here. Or maybe I'm misunderstanding the question?

 

[Pascal]

well, the problem is when you use a large bank and stay a full day on inverter. Betweenn fridge, ice maker, lights, etc... you will need to put back anywhere between 300 to 500 AH in your battery bank.

using the typical OEM - standard - stand alone charger that may be as much as 8 to 10hours during which you need to run the genny (unless you're back at the dock)

Typically, inverter-chargers have high amp. charging, as much as 150amps on 3000W inverters. this works out really well as you can just run the genny 3 to 4 hours in the evening and then you're good for another 20 hours.

But if you are using the built in transfer switch, you need to have two inputs... one to power-pass thru your loads and one to charge.

I was looking at the Outback for a friend who need to install an inverter and from what i see, it only had a single 30amp input.

When you are connecting an inverter-charger to your house bank, you may be better off disconectiong that bank from the original charger and recharge with the inverter-charger which will be much faster, assuming your bank is big enough.

 

[Buccaneer]

OK, I was thinking to use the Stbd bank for the inverter. (Stbd is for the Genny and Stbd side 6v92 only. Port bank is for the house and Port side starter. ) Then I was thinkng to set up a separate starter batt for the Genny (just in case).

And this isn't a 32v system. Its "just" the 48, not a 53.

Walt, Bob, have you done this on yours?
Anybody else?

 

[Pascal]

if you're goign to be running the fridge on inverter (assuming average full size fridge) you're are going to need some extra batteries in there.

Also depending on the type of batteries you have, they might not handle the repeated deep discharge for long and soon you'll find yourself very dependent on the paralalel solenoid.

indeed, using a dedicated battery for the genny is a good idea but you should consider enlarging the bank used for the inverter.

 

[SKYCHENEY]

I hooked my inverter to the port bank. My logic in this is that if the inverter/house bank is ever run down to the point that it won't start the port engine, the stbd bank will still be available to start either the generator or stbd engine. If you use the stbd bank, you risk running that bank down and the port house bank as well with the normal house loads. Adding a separate battery dedicated to the genny is one solution, but not necessary if you just use the port bank for the inverter.

BTW, my port bank supplies plenty of amp-hours for my 3.3KW Outback without adding extra batteries. It will run our large side-by-side overnight as well as other normal house loads in a 24hr period before needing recharge.

 

[Brian Degulis]

well, the problem is when you use a large bank and stay a full day on inverter. Betweenn fridge, ice maker, lights, etc... you will need to put back anywhere between 300 to 500 AH in your battery bank.

using the typical OEM - standard - stand alone charger that may be as much as 8 to 10hours during which you need to run the genny (unless you're back at the dock)

Typically, inverter-chargers have high amp. charging, as much as 150amps on 3000W inverters. this works out really well as you can just run the genny 3 to 4 hours in the evening and then you're good for another 20 hours.

But if you are using the built in transfer switch, you need to have two inputs... one to power-pass thru your loads and one to charge.

I was looking at the Outback for a friend who need to install an inverter and from what i see, it only had a single 30amp input.

When you are connecting an inverter-charger to your house bank, you may be better off disconectiong that bank from the original charger and recharge with the inverter-charger which will be much faster, assuming your bank is big enough.

That's exactly right with the Outback when you come off inverter and onto shore or gen your limited to 30 A for charging and the loads running thru the inverter. The charger will taper down if the total load gets close to 30A but it's a pain to deal with. Mine was set up that way originaly and I changed it to a manual transfer for this reason. I still have the Lamarche charger in the boat but it's much smarter to charge with the Outback as Pascal said the capacity is higher in adition it's new technology smart charging and much better for the batteries.

Brian

 

[MikeP]

I'm not understanding the issue when you say, "when you come off inverter and onto shore or gen your limited to 30 A for charging and the loads running thru the inverter"

If I'm not using the inverter (the genny is running) - what are these "pass through loads" you and P are referring to? I understand the "load" that would be going to the inverter to charge the batteries but if I'm not using the inverter to provide AC to the boat, what other load is involved?

 

[SKYCHENEY]

I'm not understanding the issue when you say, "when you come off inverter and onto shore or gen your limited to 30 A for charging and the loads running thru the inverter"

If I'm not using the inverter (the genny is running) - what are these "pass through loads" you and P are referring to? I understand the "load" that would be going to the inverter to charge the batteries but if I'm not using the inverter to provide AC to the boat, what other load is involved?

I think this would only be if you set it up with a subpanel that passes thru the loads all of time for those loads in that panel. If you just use a transfer switch, you would then be selecting the input source of either inverter or gen/shore and this would not be an issue.

 

[Skip]

I installed a 3.0KW inverter with 650AH of batteries two years ago, and I found that my old refrigerator really ate the AH. I could not get over 7-8 hours of carrying the house load before the system would trip off due to low voltage. I added another bank 250 additional AH, and that gave me the ability to run the boat on inverter throughout the night. I plan on replacing the refrig this or next year (when I replace the genset), and a more efficient refrigerator should greatly solve the problem.

The other thing I did to help extend battery/invertor life was to freeze some blue ice bags pierside, and move them over to the refrig at night when we went on invertor. I place them high on the top refrig shelf, and that added cooling extended the batteries over 1 hours longer.

The older refrigerators are an unbelievable drain on the battery bank!

You also want to make sure you don't put large draw items- like the water heater on your invertor system. I restricted the invertor to basically servicing the upper salon 110v outlets (for TV/music/lighting), and two outlets in the galley plus the refrigerator. I put the eight invertor outlets/refrig on individual circuit breakers to have the ability to manually control the network.

Lastly, I am replacing the heavy old hatch to the genset space under the gally to make it easier to service the battery bank. I'm having an aluminum hatch that is hinged in the middle to get aout 50 pounds of weight off the hatch. I will probably have to add insulation to the underside of the hatch to keep the noise down, but I'm going to wait and see how bad the noise level is with the genset running.

 

[Pascal]

Skip,

my 18cuft fridge/freezer is about 10 years old so it's hardly efficient but we get 20 to 24 hours out of the 880AH bank. Lower the Tstats as low as possible. Also make sure you dont' have too many AC lights on... they dont' seem like much bu it adds up... 6 incandescents at 60W will use up about 40AH...leave that on all evening and that's 1/3 of the usable power in your 650 AH bank!

Mike,

I am refering to inverters connected to use teh built in tranfer swtiches (Outbacks, Freedoms, MS3000s, etc...). when connected the way the manufacturers recommend, you put a 30amp breaker on your AC panel to feed the inverter. From the inverter it goes to a subpanel for the circuits that are to be inverter powered (lights, outlets, fridge, etc...). By sub panel i dont' mean a separate panel, just that ou goup your non inverter and inverter loads together, moving breakers along and cutting the bus in the back to isolate them.

when AC power is present (shore or genny) the inverter is in pass thru mode: power flows thru the relay and the inverter is off line.

When AC power is shit down, the inverter automatically switches over and powers the circuits on your sub panel.

If you have only ONE input (as on the Outbacks) you can only send 30amps to the inverter. This means that when you are recharging the batteries, these 30amps are shared between the charger and the loads that pass thru the inverter. So let say you have the fridge,a few lights, TV, etc... totaling about 20amps, you only have 10amps left to charge the batteries, which means that recahrging will take 3 times longer. No problem at the dock but on the hook you will have to run the genny 3 times longer!

obviously you dont' have that issue because your inverter output is connected to your loads thru an external switch or relay so your inverter-charger only uses the 30amp input to charger.

but one of the benefits of those combo units is automatic operation (kick in when AC power goes off) and not having to install any external switches or relay. So a large inverter/charger with built in transfer switches and only ONE input doesn't make much sense unless you already have the external transfer switch/relay.

 

[Brian Degulis]

I'm not understanding the issue when you say, "when you come off inverter and onto shore or gen your limited to 30 A for charging and the loads running thru the inverter"

If I'm not using the inverter (the genny is running) - what are these "pass through loads" you and P are referring to? I understand the "load" that would be going to the inverter to charge the batteries but if I'm not using the inverter to provide AC to the boat, what other load is involved?

Yes it's the loads that pass thru plus the charging load. When I set mine up I decided what would be powered by the inverter and hooked those loads up to the inverter. So in order for those items to get power it must come from the inverter either in invert mode or just passing thru in charge mode. The max input to the inverter is 30A so if the caharger needs 20A that only allows 10A to power those loads. This became a problem because when I came off inverter the batteries needed to bulk charge so most of the 30As was going to charging leaving very little for lights fridge etc. The unit senses the load and reduces the charge rate so as not to trip the breaker which ment charging would take a lot longer. So I rewired it with a selector for shore/gen or inverter and that solves the problem but it no longer switches to invert mode automaticaly I have to switch it. I don't like that because if the shore power goes down when no one is on board the fridge stops. I would prefer it be automatic but I'm not seeing an easy way to do it. The idea of 2 inputs into the inverter would be a real improvement and would solve this problem.

Brian

 

[SKYCHENEY]

I have a separate smart charger that I really like so I did not hook up the Outback to be used as a charger. I put in the selector switch as you did, Brian. I wonder, though, if the inverter pass through could have been used with the charger portion just disabled. If that can be done, then all you would need is a separate charger and you would have your automatic switching during power loss without the worry of the charging circuit tapering off during high load times.

 

[Brian Degulis]

Sure that would work I've got the controller and could just turn off the charger but I really don't want to buy another charger. I'm sure something could be made or bought to switch it if the shore power failed. Maybe one of our electrical engineers can create a wiring diagram using some contactors?

Brian