If my boat is plugged in to shore power, and the battery charger is turned off, do the lights, fridge, etc. continue to work but off shore power instead of battery power? I do have an inverter, and I guess it converts dc to ac for appliances when NOT plugged in, but I need to know if I can live on the boat, plugged in, without using the house batteries.
Beginner electrical question
- Thread starter Zeus2012
- Start date
The lights and fridge (assuming they're DC) will run off the batteries. The AC from shore power is completely separate, with the only way of getting DC from AC being the battery charger. If you're at the dock and don't want to tax the batteries leave the charger on and it should cover the DC loads without running the batteries down. The inverter provides power to some AC loads when you're not connected to shore power. Why would you want to leave the charger off?
Because we have a hot battery, hydrogen sulfide smell, charger fan running nonstop, the yard cannot do anything until tomorrow, plus they told me battery chargers should not be left on perpetually. Ours has been on pretty much ever since we bought the boat and we have been living on it since August 2015. So I have turned everything off on the boat and flipped off the breaker on shore but would like SOME power.......
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With a constant partial load, you can have issues with a charger (or even some charger inverters) with lead acid batteries overheating and/or going through water.
What type of charger do you have? Is it a "smart charger"? Do you have an inverter/charger?
What batteries (type, capacity, age, etc.) and how are they set-up (e.g. jointed by one-off-two-both switch, combiners, etc.? Are they both lead-acid or gell cells; or different? etc.) How have you "treated" the batteries? How old are they?
My guess: Your batteries are clearly "toast"? If you live in the boat, you might get by by checking the fluid levels with lead acid batteries -- but you clearly need a good charger/inverter that won't overload your system.
Anyway, some more info would be helpful.
What type of charger do you have? Is it a "smart charger"? Do you have an inverter/charger?
What batteries (type, capacity, age, etc.) and how are they set-up (e.g. jointed by one-off-two-both switch, combiners, etc.? Are they both lead-acid or gell cells; or different? etc.) How have you "treated" the batteries? How old are they?
My guess: Your batteries are clearly "toast"? If you live in the boat, you might get by by checking the fluid levels with lead acid batteries -- but you clearly need a good charger/inverter that won't overload your system.
Anyway, some more info would be helpful.
Nothing wrong with leaving a battery charger on continuously, assuming it's a good quality charger, operating correctly and running well within its capacity.
As David Sailor pointed out, your boat has two systems, AC and DC electricity. DC is battery or from a battery charger and is separate and independent from the AC system except that the AC powers the battery charger which will charge the battery and run any 12V loads. If yours is a typical boat all the lights, pumps and most everything else operates from 12V DC battery or charger.
As David Sailor pointed out, your boat has two systems, AC and DC electricity. DC is battery or from a battery charger and is separate and independent from the AC system except that the AC powers the battery charger which will charge the battery and run any 12V loads. If yours is a typical boat all the lights, pumps and most everything else operates from 12V DC battery or charger.
So you're really talking about a short term solution until you can get the battery and charger looked at? If that's the case then your best option depends on whether the fault is in your charger or batteries. If the problem is the charger you can probably go a day or two on minimal loads without running the batteries too far down. If the problem is a battery then you won't last as long.
In any case, I agree with Skipmac that a smart charger should do no harm to leave on full time, once the current issue is worked out.
In any case, I agree with Skipmac that a smart charger should do no harm to leave on full time, once the current issue is worked out.
Some "quality" charger's regulators are fooled by smallish background loads into believing that the batteries require more charge than necessary. They "load-up" the system. This is especially the case where the banks are split with the load coming from one bank and the changer not independently reading the second bank (which needs no serious charging).
I had a friend with a brand new Beneteau a years ago that had a factor installed system. His refrigeration was a European 12v system that required very frequent runs to maintain the temperature. He ended-up with the sulfur dioxide smell in the aft cabin (your rotten egg experience too) -- the solution was to go to gel cells, modify the changer and (as I recall) regulator.
I had a similar experience with our boat before we installed an Inverter/Charger using a quality "simple" charger. We replaced our charger and batteries at the same time.
I'd caution against AGM's because they are more sensitive to sulfation, in my experience with low, constant loading and topping-up. The Gel Cells may not be as high performance, but they will work fine.
I had a friend with a brand new Beneteau a years ago that had a factor installed system. His refrigeration was a European 12v system that required very frequent runs to maintain the temperature. He ended-up with the sulfur dioxide smell in the aft cabin (your rotten egg experience too) -- the solution was to go to gel cells, modify the changer and (as I recall) regulator.
I had a similar experience with our boat before we installed an Inverter/Charger using a quality "simple" charger. We replaced our charger and batteries at the same time.
I'd caution against AGM's because they are more sensitive to sulfation, in my experience with low, constant loading and topping-up. The Gel Cells may not be as high performance, but they will work fine.
Thank you! That is exactly what we did.
Thank you everyone! It seems like every time we have a problem, I am home alone, my husband doesn't answer his phone, and the dock neighbors would like to help but don't feel confident enough. And, today the yard guys were both unavailable. I can handle house electrical, but not boat. Definitely learning as we go. I am now an expert in marine head problems.
Thank you everyone! It seems like every time we have a problem, I am home alone, my husband doesn't answer his phone, and the dock neighbors would like to help but don't feel confident enough. And, today the yard guys were both unavailable. I can handle house electrical, but not boat. Definitely learning as we go. I am now an expert in marine head problems.
If you have a hot battery emitting gases you need to remove it and have it tested. It could be a bad battery or a bad charger. Certain items and fixtures will be 12V while others will be 120V. The usual 12V are lights, pumps, refrigerators, radios, propane switches, instruments while the typical 120V are usually appliances like A/C , water heaters, microwave ovens and some refrigerator/freezers and inverters. When the engine is not running and alternator is not turning then the only source of 12V (unless equipped with a step down transformer) are the batteries and the battery charger. The 12V system and the 120V systems are separate and will be separated at the main electrical panel. The breaker switches will indicate the item they serve and be located in their corresponding section of the panel. It has been said that maintaining a battery charger connected for long periods of time is harmful to the longevity of the batteries but I will say I do not know how significant that damage may be as I keep the charger on 24/7 except when sailing and have not noticed any undue premature battery failures. In battery replacement Dollars a few here and there are secondary to convenience at least for me.
What they all said... Most everything but the outlets are 12v. A crap charger will overcharge the batteries.
But your fridge may be 12/120v - many are. So if my boat is plugged into shore power, the fridge runs off 120. If your smelling hydrogen sulfide, definitely remove the charge from the battery. I turn the 12v breaker to the fridge off when I'm plugged into shore.
But your fridge may be 12/120v - many are. So if my boat is plugged into shore power, the fridge runs off 120. If your smelling hydrogen sulfide, definitely remove the charge from the battery. I turn the 12v breaker to the fridge off when I'm plugged into shore.
Also check to see if the charger has a outdoor temp switch. Mine has a cold-warm-hot temp selector switch to compensate for summer-fall-winter temps in the battery box. Should be on the front/end of the charger.
The boat is in San Francisco Bay, Bill. It's not like the (normal) Chesapeake.
Zeus2012: Some good advise above. If you can't get the "yard" out to help you.
Zeus2012: Some good advise above. If you can't get the "yard" out to help you.
- Are all the batteries out gassing? If only one or two are, then disconnect those (or use the battery switch to not charge or discharge them.
- Are the batteries lead acid batteries (i.e., do they have removable caps on the top which you're supposed to put distilled water into to keep the plates covered)? If so (with GLOVES ON) can you fill add water to them? Are the batteries dried-out?
- If you need a simple work-around. Disconnect the current batteries from the boat and charger and put ONE inexpensive battery with the charger connected to it its place. You are living on the boat, you have the charger connected so that the battery is just an intermediary. You can buy the battery at a discount store -- it's just a temp fix. It's not going to be discharged.
- Do you have a voltage meter? (If there is a discount store, you can buy a simple digital meter). The Beneteau should have meters on the panel. What do they show?
- If you give us some more info, then maybe we can help you through this...