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Solar Regulators Pulse Width or MPPT ?
 

Solar regulators how to choose between Pulse Width (PWM)  or  MPPT (Multi Power Point tracking). we can now look at sourcing Charger controllers or solar regulators for your systems batteries. Before I explain the differences between (PWM) and (MPPT) we need to find out what unit is going to suit out system.

A good place to start is by taking the AMPS from your (PV) or solar panels. Lets say that number comes to 15 AMPS. What we then do is get a solar regulator that will exceed that 15 amp limit say the say the Morningstar 20A from solar online -  Below I have explained the two main types of solar regulators.

 
Pulse width Regulators
 

There are many types of regulators on the market which are simply x on/x off or pulse with controllers (PWM) are sold state.

 These types of controllers will do the job, but they will only charge the batteries in a limited way, not using any type of battery sensing voltage. This can can if left unchecked cause issues in the long run for the batteries. They do sense what voltage you have an the batteries, and or limit the ammount of PV volatge from the solar array. Hence they may over charge a lead acid battery causing the electrolite to evaporate or turn into sulpur oxide hense exposing the lead plates, causing them to bend or buckle under the added temperature. This will most probibly cause a open circuit fault or in the worst case (may explode if it comes in contact with a naked flame).

Solar Regulators MPPT (Multi Power Point Tracking)

There MPPT regulators do all that the above (PWM) regulators do with two main advantages, the first being these will monitor and deliver the maximum voltage to your batteries from the array basicly giving you 30% power for your systems needs.
The other is a 3 stage charging option witch means stating of at (bulk) chatge until the batteries reach a voltage of 14.4, then switching to a absorb or aceptence charge at that voltage for a min of 3 hours or 180mins, but the regulator will sense the battery volatge and switch to float at 13.6 volts to maintain the batteries. This means you are less likely to damage your battery bank.

Also as an addition to these more up market MPPT regulators they will have an option for a Battery Temperature Sensor (BTS) will will also regulate the chatge via temp as well as voltage.

If you have the money go with the Multi Power Point Tracking option, if you want to know more about multi point tracking click on the Page below:

I have fitted both of these regulators bought from the friendly staff at Solaronline;

Bluesky SB3024DI (MPPT) Solar regulator

The Bluesky Sb3024di  30amp (rated)

Xantrex XW 60A (MPPT) From Solaronline

The Xantrex XW 60A MPPT Solar Booster Regulator  (60amp) rated