12v 600watt water element dump load

[kbhale]

I need some help. I have a 6 gallon hot water tank, (that was phased out by solar water) a 12 volt 600 watt element, two 12 volt batteries that I just want to keep charged for emergency and  this 12v 25amp dump load controller.

 http://shop.missouriwindandsolar.com/product.sc?productId=12&categoryId=3

Later on,  I hope add a 500 watt turbine.

http://shop.missouriwindandsolar.com/product.sc?productId=163&categoryId=2



Here is My question. Should I / could I, tie a few solar panels to the controller to dump load to the element. I don't plan to use the batteries, just want to keep them charged. They are just a little different size from the batteries in my main bank. I'm not looking for hot water. Just maybe a little pre heating.  The batteries are Alpha sealed type.

[Flux]

Not sure what you have or want to do.

If you have a solar controller that should be able to keep the batteries charged without a dump load.

if your controller is mainly for wind and only works in diversion mode then you can use it to dump any excess power from the panel to the heater. The only requirement is that the controller can handle the current of a 600W heater at 12v. This is in the region of 50A so it will need to be a 60A controller. If it is rated less you will have to find another source of dump resistor.

Flux

[ghurd]

To keep a couple small 12V charged for back up power, that will not be used often, wind is pretty silly on multiple levels.
Cost, complexity, maintenance, and unpredictability come to mind.

The first thing you should do is reevaluate the choice of dump load controller, then throw it away and get something decent before it causes more damage than it prevents.
(Hint- 3.2V of undefined or controlled hysteresis in a 12V system should be called a battery ruining device)

I am confused because you have a "controller" and water heater.
Want to add a 500W turbine, later.
And not sure if adding solar is a good idea?

Sounds like the backup battery needs a 50W PV and an SG4.

Heating water with electrical RE and a small system, even preheating, is rarely a good idea monetarily, carbon footprint, embedded energy, or whatever.
Best to spend that money on upgrading the main RE system.
G-

[OneToRemember]

I saw some of these for sale on ebay.co.uk

They were designed to be fitted in a spare tapping at the bottom of a hot water cylinder to supply extra heating when spaer power was available.

[Bruce S]

I need some help. I have a 6 gallon hot water tank, (that was phased out by solar water) a 12 volt 600 watt element, two 12 volt batteries that I just want to keep charged for emergency and  this 12v 25amp dump load controller.

Later on,  I hope add a 500 watt turbine.

Here is My question. Should I / could I, tie a few solar panels to the controller to dump load to the element. I don't plan to use the batteries, just want to keep them charged. They are just a little different size from the batteries in my main bank. I'm not looking for hot water. Just maybe a little pre heating.  The batteries are Alpha sealed type.

Missouri W& S? you located in Mo?
Okay to your questions:
Here's a few ideas, but will need a bit more, info.
1.) Size of PVs to keep batteries charged
2.) Amp rating of 12Vdc batteries.
3.) Other items to be used while pre-heating isn't needed.
Reasons: The PVs ability to keep the batteries charged up and on float if FLA will make a big difference.
The controller they have is way more expensive that what you'll want to use this setup for, since it's for water pre-heat and dump.
That bugger is 105.00 USD!! contact Ghurd and get one from him, even pre-assembled will still save you about 80.00USD and it's much more fun to use for what you're wanting to do.

Don't add Wind to this system, save the money they want for the 500 watt unit and keep going with the Solar route for know.
Once you get to were the controller is always dumping to the 6 gallon water heater, get more batteries and start using them for other cool stuff, like a solid state beer fridge that will use 80 watts/hr to use the extra power available...

Have Fun  too!!
Bruce S

[kbhale]

See if I can word things better.

I own a   Flexcharge 12v 25amp charge controller and a 12volt 600watt element and a used tank to put it in. I also have an extra 12 volt battery or two that I'm keeping around for emergencies.  I would like to use the flexcharger now for some extra solar panels.  

So I do not have to buy another controller for now.
I do not known how big or what type system I want/ need yet.

My Sunforce charge controller is going to be max out at 30 amps.

Soon I will have 20 more amps that I need to do something with.

If I use the flexcharge controler tied to a fully charged battery, would the amperage skip the battery and go to the Dump load / hot water element?
(600watts /12 volts =50 amps). Would 20 amps be too small of a dump?

It has sunk in a 500 watt mill is too big for the controller.
 Thanks

I do need a cooler to hold five gallon kegs.

[ghurd]

Their documentation is not exactly clear,
but you have a 25A "controller" and a 50A load.

The diversion load is listed as 'optional'.  I have to assume that means the PV power goes to the load.
PVs are like a current source.  20A.
The 50A load is about 0.28 ohms. 
I^2R=100W in the 600W heater, at the very best.  So much for all that bragging about how efficient it is.   

With wind, the diversion load is still listed as required.  Try to realistically size a suitable load for that.  It can't be done.
Especially if you want to efficiently heat water, without destroying the turbine.
 
That controller does not even have a provision to stop night time discharge through it, like a blocking diode.

350W of PV, wire, brackets, water heater, 12V element, plumbing, etc. to put 100W peak into the water? 


For the system to work efficiently, or possibly work at all, need to get a decent controller that functions like a normal controller.  And that one sure ain't it.

[kbhale]

The flexcharge controler is little better than a paper weight.