Thoughts on installing a inverter on my boat

chris0061

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looking at a bestek power inverter Rated power:2000w, Max power:2300w,Peak power:4600w. My thoughts are that I can install this on one battery, plug my shore power into it and keep the battery charged as I run my electrical on my boat off shore power. Any thoughts on this?
 

ssobol

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As I understand it you are going to hook an inverter to your 12vdc system to give you 120ac and then hook up the shore power to maintain the battery level (replenish the drain from the inverter). Correct?

First, if you do this will your battery charger recharge the battery as fast as you drain it? If you are taking 2000 watts from the battery, that is 166 amps. Most on board chargers will give you 10 to 15 amps back into the battery.

Second, if you pull 2000 watts out of a group 24 battery it'll last about 20 minutes.

Third, if you are hooked up to shore power anyway (to recharge the battery) what do you need the inverter for? You have 120ac right there. Just add outlets to your 120ac circuit.
 

Silvertip

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The device the OP is talking about is not a traditional inverter (12 volts in/120 AC out). It goes by a number of names but consider it is a combination unit that you input 120 vac and that is fed through to 120 volt ac outlets and other 120 vac appliances. The device also has a built in charger to maintain a battery bank when connected to shore power and it may also include a 12 volt power bus to power 12 vdc appliances when connected to shore power or from the batteries.. That battery bank can then power the inverter when away from shore power and you still have 120 vac. This is definitely not the system or scheme you explained.
 

ssobol

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From the information on the Besttek website, their power inverters take 12VDC and turn it into 120VAC. Their description for a 1000w unit (their website does not list 2000w inverters):

This unit can invert the DC provided by car, vessel, and storage battery etc. to AC power to ensure that you can use power outdoor or at place without AC power supply. This unit can be used with such electronic devices and electric appliances as mobile phone, notebook computer, digital camera, TV, fan, refrigerator, games machine, DVD, MD, light, instrument, solar panel, and outdoor work. Please make sure that your total rated power using in this unit is less than 1000w.

This description of the unit that was mentioned by the OP was what I based my comments on. Descriptions of the Bestek units on Amazon are essentially the same (though they list the 2000w unit). If there is a unit that does what you describe, it seems that Bestek does not supply it.

I have heard of battery chargers and inverters, but not inverters with battery chargers built in. I would be interested in putting one in my boat. Please post a link with some information.
 

chris0061

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I'm not going to be hooked up to the dock shore power I'm saying running my Shore power to the inverter with the 120 pig tail and the inverter does not have a charger in it my boat does that is hooked up in the shore power circuit. I see what ssoil is saying if the inverter is pulling more amps than the charger is charging then my battery would go dead.
 

Silvertip

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Me thinks you need a better plan. One that doesn't involve perpetual motion as it hasn't been invented yet. You cannot use a 12 volt battery bank to convert 12vdc to 120 vac and then use that power to power accessories as well as charge the batteries and come out ahead. It simply is not possible.
 

Scott Danforth

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Chris0061, did you read that on the internet?..... was it being discussed by a french model?

As Bruce and Silvertip pointed out, perpetual motion and free energy have not been invented yet.

you have 12 volts available. the inverter will give you 120 VAC when connected to the 12 volt source, however the conversion is about 75-90% efficient (the remainder being given off as heat). The battery charger takes 120 VAC and converts it to 13.7-14.4 volts to charge the batteries, yet the conversion is only 75-90% efficient (the remainder being given off as heat). Assuming you do not have any lights on, etc you would be draining your battery in record time just by the devices being powered on. Although you would be generating some heat.

a battery charger is intended to take shore power and charge your batteries. your shore power is being supplied by Solar, geothermal, nuclear, or some mechanical means to generate electricity. basically a power plant.

an inverter is intended to run a 120 VAC device off of a 12 volt source, however will deplete you batteries.

the available ways of charging your battery when not on shore power:
  • run the motor, charging from the alternator.
  • run a generator, charging from the generator
  • run a solarpanel array, charging from the sun.
  • run a wind generator, charging from the wind.
 

achris

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I'm not going to be hooked up to the dock shore power I'm saying running my Shore power to the inverter with the 120 pig tail and the inverter does not have a charger in it my boat does that is hooked up in the shore power circuit. I see what ssoil is saying if the inverter is pulling more amps than the charger is charging then my battery would go dead.

Sorry Chris, this ^^^ sentence doesn't make any sense. Let me see if I have it right. You have a shore power connection that is just for charging the battery. And to the battery you want to connect this new inverter. Well, I read it again, and now it looks like you want to connect the new inverter directly to shore power. You need to clarify exactly what you have hooked up and how, and what and where you want to add this inverter.

.... One that doesn't involve perpetual motion as it hasn't been invented yet. You cannot use a 12 volt battery bank to convert 12vdc to 120 vac and then use that power to power accessories as well as charge the batteries and come out ahead. It simply is not possible.

Are you thinking your battery is going to charge itself?

Silvertip and Bruce. At no stage did Chris say he wants this 'free' power you're referring to. I'm not sure what he wants, but never was there a suggestion that he'd be recharging the battery from its own output (and I suspect the 'yea' comment he made was acknowledgement of that, very tongue in cheek)....

Chris.......
 

bruceb58

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Silvertip and Bruce. At no stage did Chris say he wants this 'free' power you're referring to. I'm not sure what he wants, but never was there a suggestion that he'd be recharging the battery from its own output (and I suspect the 'yea' comment he made was acknowledgement of that, very tongue in cheek)....

Chris.......

You sure about that?
I'm not going to be hooked up to the dock shore power...
 

ssobol

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Well, I read it again, and now it looks like you want to connect the new inverter directly to shore power.

There is no point connecting the inverter to shore power. In fact, it will not work. Shore power gives you 120vac. The inverter gives you 120vac from some volts DC. If you hook up the inverter to the shore power I expect the only thing you'll get is a lot of smoke.
 

doyall

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looking at a bestek power inverter Rated power:2000w, Max power:2300w,Peak power:4600w. My thoughts are that I can install this on one battery, plug my shore power into it and keep the battery charged as I run my electrical on my boat off shore power. Any thoughts on this?

Most battery chargers are not designed for this type use and unless yours is it will burn up rather quickly.
 

doyall

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Most battery chargers are not designed for this type use and unless yours is it will burn up rather quickly.

Please disregard. Fact situation misinterpreted. (No edit available?)
 

wrench 3

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I'm not going to be hooked up to the dock shore power I'm saying running my Shore power to the inverter with the 120 pig tail and the inverter does not have a charger in it my boat does that is hooked up in the shore power circuit. I see what ssoil is saying if the inverter is pulling more amps than the charger is charging then my battery would go dead.

If you do hook your inverter into your shore power system you need to use a switching system that will prevent you from being connected to the inverter and shore power at the same time.
 

achris

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Thanks for the link Wrench. With that I was able to work out what is going on in this thread....

Directly from the website.

There are two modes of operation associated with an inverter/charger:

Inverter Mode:
  • Direct current (DC) from the vehicle?s batteries is transformed into alternating current (AC) for use with you household electrical appliances.
  • Charger Mode:
  • Alternating current ( AC) is taken directly from shore power (or other AC sources) and passed directly to your household appliances . At the same time, the incoming AC is also converted to DC to recharge the vehicle?s batteries.

So, back to the OPs original question... Yes, that would work.
 

wrench 3

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Achris, I think you need to move this to the "Humor" forum. It's the best chuckle I've had in a long time.
 
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