Generator to Battery Charger connection

[sully75]

Ok so I know that this is not recommended but it's also inevitable. I'm installing radar on an outboard equipped boat and it is likely to burn through my power bank pretty quickly if I don't have sun to power my solar panel.

So I'm installing a Sterling battery charger. I'm unclear what the best way to connect the portable generator to the charger. Would I wire the generator through my shore power system somehow and then connect the charger to that? Or can I connect the generator straight to the charger?

If I asphyxiate myself I will only blame myself.

Thanks


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[Lepke]

Usually a portable generator is connected to the shore power inlet. Some generators have a separate 12 volt charging line. Modern radars don't have high power requirements. Unless you need to run continuously, a spare battery may meet needs.
A battery isolater made for 2 alternators would be a good way to tie in a portable 12 volt source.

[Stu Jackson]

Originally Posted by Lepke

Usually a portable generator is connected to the shore power inlet. Some generators have a separate 12 volt charging line. Modern radars don't have high power requirements. Unless you need to run continuously, a spare battery may meet needs.
A battery isolater made for 2 alternators would be a good way to tie in a portable 12 volt source.

Some generators have a separate 12 volt charging line.
Useless for charging batteries. One requires 14+ V to cvharge 12V batteries. Use the 120V outlet of the generator to power your Sterling via the boat's shorepower inlet.

Battery isolators are also pretty useless and 1980s technology, because they drop voltage when what you actually need is as much voltage as you can get. What is used these days are relays, like Yandina combiners or BlueSea ACRs.

[sully75]

I have a smart plug for my shore power inlet. Would I connect the generator to that, or hardware a separate inlet, specifically for the generator?


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[Cadence]

Originally Posted by sully75

Ok so I know that this is not recommended but it's also inevitable. I'm installing radar on an outboard equipped boat and it is likely to burn through my power bank pretty quickly if I don't have sun to power my solar panel.

So I'm installing a Sterling battery charger. I'm unclear what the best way to connect the portable generator to the charger. Would I wire the generator through my shore power system somehow and then connect the charger to that? Or can I connect the generator straight to the charger?

If I asphyxiate myself I will only blame myself.

Thanks


Sent from my iPhone using Cruisers Sailing Forum

All you need to do is plug your dock line into the gen.. If it is outboard powered where can you place the gen. so that you don't asphyxiate yourself.

It maybe over kill. As someone said, add a battery. Someone else commented the new radars use little power even the old ones had a sleep mode which kept things warm so you could look around periodically without waiting.
JMHO

[a64pilot]

Have you already bought the generator?
If not there are two different but nearly identical Honda's, 2000's anyway, one is called the companion I believe and has a receptacle that your shore power cord fits, no adapters.
It does not have the 12VDC outlet, but that is nearly useless as its a very low DC output, about what your outboard is capable of.
But yes, plug into shore power, that way when batteries acceptance rates slows, you can run fans, TV's and anything else your generator can support.
I believe though that you don't have a real "ground" with a portable generator, so be aware of that.


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[sully75]

I haven't bought the generator.

I asked about this on a site with a somewhat esteemed contributor and he indicated that I might expect to have power issues. Currently I'm doing fine with a 100w solar panel and 2 79ah AGMs. I have a full charge by 8 am normally. But I haven't run hard in quite a while and previously didn't have a good means of measuring my charge level.

I'm open to adding another one of these AGMs. But my guess is that I will still be somewhat short?

I bought a traditional style radar but I think it's a mildly lower powered version. A Furuno 1623

I was thinking I could get the battery to a full charge, disconnect my panel, turn on my gps, running lights, and radar and leave them on for 12 hours and see how much my charge goes down? Currently I'm just using a simple voltmeter connected to my panel.

I also have a 5a alternator on my Tohatsu sailpro 6hp. I'm pretty unclear as to how significant this will be in adding power.


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[a64pilot]

Originally Posted by sully75

I have a full charge by 8 am normally.
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No, you don't, you think you do, but you are not fully charged, only way I know of to determine full charge is by monitoring the amps going into the battery
I have an AGM bank myself, and even the manufacturer of the batteries will tell you you can't get to a full charge with Solar alone and AGM's will die an early death if you don't fully recharge them at least weekly, and probably equalize monthly, assuming your battery can be equalized.

Even if you had a Kilowatt of Solar, your not getting to 100% full charge, it's not the size of the available charge source, it's the battery acceptance rate and number of hours required, there just isn't enough hours of usable daylight to fully charge an LA battery, so the generator is not for adding more amps so that you can charge the battery faster, it's for extending the charge time by running it either early in the morning or late in the day.
Morning is better as that is when the battery can take the amps that the generator can throw at it, late in the day your trickling it in.

But then you get into the economics of the problem and whether or not your willing to spend the bucks for a generator, store and maintain it, keep fuel on board for it, listen to the darn thing etc.
It may be that going to Golf cart batteries when your AGM bank dies, with the idea of replacing them as necessary is more palatable than a generator.

Flooded lead acid batteries are more tolerant to partial state of charge cycling than AGM are and are much less expensive, and the least expensive is a golf cart battery, and they seem to be pretty decent batteries too.

[sully75]

Well the Genasun charge controller says I have a full charge for whatever that's worth.