BZ Products MPPT500 MPPT Charge Controller 42A 12/24/48 VDC

The MPPT500 is a great charge contoler for a stand alone solar panel sysytem. It is one of the few that not only boosts the current going into the batteries but also will fully top off the batteries without overcharging and boiling them off. Other charge controlers that have MPPT and Absolute float voltage contol that gradually ruduces the curent as the batteries top off cost twice as much per watt and don't come with the 5 year warrentee. I have 1600 watts being controled by four (4) MPPT500 units from a mix of different size panels running either a 2 pannel series/Paralel or a 3 panel series/paralel (24 volt(35 volt)/36 volt (47 volt)) of 12 volt panels (nominal 17.6 volt outputs each) and the MPPT coverts the voltage automaticly to the 12 volt RV type system I have and boosts the current by taking the extra 3 volts over the 14.6 needed and convering the raw power to more amps to the batteries. Other shunt type charge controlers can not convert. They just shunt the panels and disconect the battery when the average voltage goes above 14.1 Volts and that happens when the batteries are only 70% full. MY four MPPT500 units are used parallel and do not interfear with each other so the only limit to how much wattage you want to use is the Number of MPPT Units you wish to connect to the batteries and the total watts of penels you install. I limit the input at 420 watts each system to reduce the heat the charge controler produces. My fist unit failed after 4 years when the plastic screws that heat sink the diodes melted and fell to the bottom of the controler's box and they lost their heat sink. BZ products replaced the unit and they told me to series the panels instead of parraleling all the 12 volt panels because that reduces the input current and make the MPPT portion more efficient with there new software programed to be most efficient closer to 48 volts. I also took a 2 watt 3 inch computer fan and use it to cool the enclosure/heat sink. Works great.

I have had this for 2 years, works fine. I would prefer if it had 3 stage charging. Easy to install, no mechanical defects.