Date: Wed, 18 Sep 2013 10:24:48 -0700
Reply-To: Vanagon <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Vanagon <camping.elliott@GMAIL.COM>
Subject: Re: solar charge controller
In-Reply-To: <CABx3TkWKQUQMrThC6Cy_Qg=E_4Yr5WX61kXixxLW=j8==X_+uQ@mail.gmail.com>
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Yes, Morningstar do make a good controller. The Blue Sky 2000e that I use also permits adjustment to what your battery mfgr recommends as full-charge and float voltage, like the Morningstar it has accommodations for a remote battery temp sensor (recommended for camping since batt temps can vary with the conditions), and it also has an "equalize" mode for battery maintenance. <http://www.trojanbattery.com/batterymaintenance/equalizing.aspx>
Kind of like how a transmission matches the engine to the road, MPPT style controllers match the panel to the battery more efficiently than simpler controllers. For example, this controller has adjusted its input impedance so the panel is operating at its maximum power level under the conditions (morning, thin sunlight) and the panel is delivering 5.1 amps into the controller, and the controller is outputting 6 amps into the battery. Faster recharge.
BTW, the panels (I have two) printed labels state that under ideal conditions with a load that permits the panels to be at 17.4 volts, they will put out 2.9 amps each. Were the panels to be directly connected to the battery, or through a pwm controller, they would not be at their idea voltage and thus not be putting out their maximum current. With the MPPT, their rated maximum current is being delivered to the battery.
I like MPPT. It increases the odds that I will be able to get the house battery fully recharged before night. Otherwise the battery will go lower and lower every day. And I'm here on a 14-day campout without access to power, while running LED lighting and a Vitrifrigo refrigerator.
Sent from my 1963 maroon and cream 702B Western Electric Princess phone.
On Sep 18, 2013, at 7:58 AM, Ryan Press <ryan@PRESSLAB.US> wrote:
> On Tue, Sep 17, 2013 at 7:35 PM, Timmy Evens <monkey_lips@yahoo.com> wrote:
>
>> what brand/model charge controllers do folks recommend? ease of
>> installation? cost?
>>
>> thanks,
>> tim
>
>
>
> I tried a couple cheap controllers and they all had poor voltage
> regulation. This will decrease the life of the battery. I ended up with a
> Morningstar Sunsaver MPPT, I got mine for $200. Very happy with it.
>
> http://www.morningstarcorp.com/en/sunsavermppt
>
> Out of the box the voltages can be configured to charge a few different
> battery types, or with a special cable it can be programmed via computer to
> anything you want. It also has an optional remote battery temperature
> sensor which I would recommend using. I have seen over 20 F difference
> with the battery in the stock battery box; they recommend using the sensor
> at 5 F difference or above. This also extends the life of the battery.
>
> Ryan
