CHARGE CONTROLLER

Charge controller is basically used to charge solar batteries from Solar Panels. Solar panels normal give 15-17 volt, charge controller converts that to 12-14 volt and charges battery. Battery often need a higher voltage than it already have to charge the battery. Charge controller prevents batteries to be over charged. And stops to charge when battery is fully charged. And it will give longer life for battery. You can also use blocking diode instead of charge controller. But there are some negative effects of blocking diodes. If you do not use charge controller and just use a blocking diode, so battery can be over charged and damaged. If you is using big solar panel system so it is better to have an advanced charge controller. That gives you complete statistics of how much volt and ampere it have charged battery. Advanced charge controllers also show you how much ampere is on batteries. Charge controllers can automatic disconnect battery if it is going to be empty. 

 

or bigger systems like tube well or water pumping they are used high voltage charge controllers, called MPPT (Maximum Power Point Tracker) charge controllers. MPPT charge controller can convert dc-dc voltage. Example used in 24, 38, 48 volt systems. MPPT charge controllers are used with higher power panels like 135 watt and higher panels.

 

   

 

Detail Information

Charger Controller Types

Charge controls come in 3 general types (with some overlap):

• Charge controls come in all shapes, sizes, features, and price ranges. They range from the small 4.5 amp (Sun guard) control, up to the Apollo 80 amp MPPT programmable controller with computer interface. Often, if currents over 40 amps are required, two or more 20 to 40 amp units are wired in parallel. The most common controls used for all battery based systems are in the 6 to 40 amp range.

• Simple 1 or 2 stage controls which rely on relays or shunt transistors to control the voltage in one or two steps. These essentially just short or disconnect the solar panel when a certain voltage is reached. For all practical purposes these are dinosaurs, but you still see a few on old systems. Their only real claim to fame is their reliability - they have so few components, there is not much to break.
  
  3-stage and/or PWM such Morningstar, Xantrex, BZ Products, Blue Sky, Steca, and many others. These are pretty much the industry standard now, but you will occasionally still see some of the older shunt/relay types around, such as in the very cheap systems offered by discounters and mass marketers.
  
  The maximum power power tracking ones (MPPT), such as those made by Blue Sky Energy and Outback Power. These are the ultimate in controllers, with prices to match - but with efficiencies in the 96 to 98% range, they can save considerable money on larger systems since they provide 15 to 30% more power to the battery. For more information, see our article on MPPT.
  
  Most controllers come with some kind of indicator, either a simple LED, a series of LED's, or digital meters. Some newer ones, such as the Outback MX60 and a few others now have built in computer interfaces for monitoring and control. The simplest usually have only a couple of small LED lamps, which show that you have power and that you are getting some kind of charge. Most of those with meters will show both voltage and the current coming from the panels and the battery voltage. Some also show how much current is being pulled from the LOAD terminals.
  
  All of the charge controllers that we stock are 3 or 4-stage PWM types, including the MPPT units. (in reality, "4-stage" is somewhat advertising hype - it used to be called equalize, but someone decided that 4 stage was better than 3). And now we even see one that is advertised as "5-stage".

What is Equalization?
Equalization does somewhat what the name implies - it attempts to equalize - or make all cells in the battery or battery bank of exactly equal charge. Essentially it is a period of overcharge, usually in the 15 to 15.5 volt range. If you have some cells in the string lower than others, it will bring them all up to full capacity. In flooded batteries, it also serves the important function of stirring up the liquid in the batteries by causing gas bubbles. Of course, in an RV or boat, this does not usually do much for you unless you have been parked for months, as normal movement will accomplish the same thing. Also, in systems with small panels you may not get enough current to really do much bubbling.