Analytic Systems SolarMax SMP100, Installation & Operation Manual

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Overview of SolarMax MPPT Charge Controller
Introduction
Congratulations on choosing a photovoltaic electric system for your energy storage needs. When properly planned and
installed, your system will give you decades of trouble-free service.
The Analytic Systems SMP100 SolarMax MPPT Charge Controller is a key component of your system. SolarMax accepts
a wide range of input voltages from 30-230 volts, and support a similarly wide range of battery voltages from 24 to 72
Volts nominal (battery voltage must be equal to or less than solar panel voltage). SolarMax features a patented MPPT
(Maximum Power Point Tracking) algorithm allowing you to maximize the energy harvested from your solar array.
SolarMax allows you to use a higher voltage PV array than the batteries you are charging as it is designed to step down
the array voltage, allowing greater flexibility in the choice of array for your system.
A PC communications port and software allow viewing and programming SolarMax parameters as well as data logging.
A battery temperature sensor (supplied) allows programmable compensation of the charging voltage.
How the charger operates
The SolarMax is a DC-to-DC smart battery charger that works in two ways. The charger harvests the maximum energy
from the PV (Photo-Voltaic) array using Analytic Systems’ patented maximum power point tracking (MPPT) strategy. The
controller’s secondary objective is to ensure that the batteries receive a full charge without becoming overcharged. This
is accomplished through a three stage charging process. The end result is that you can safely maintain your energy
storage system while getting the maximum benefit of your solar array.
The DC to DC converter feature of the SolarMax allows for a wide variety of PV array inputs and battery voltage
configurations. Batteries may be configured from 24 to 72 volts nominal. PV arrays may be wired up to maximum
allowable Voc (Open Circuit Voltage) of 230 volts at worse case conditions.
Chargeable battery types
This charger is designed to charge both starting and deep cycle lead acid batteries and all versions of these batteries:
• Wet Cell (flooded)
• Gel Cell
• Absorbed Glass Mat (AGM).
See your battery manufacturers’ documentation for recommendations for bulk absorption and float voltage levels.
Support for Lithium-Ion and other battery types will be provided by future firmware updates.
For example, a Mitsubishi PV-MLE270HD module has an Open Circuit Voltage of 38.4 volts at 25C, but at -25C, the Voc
rises to 120% or 46.08 volts. Dividing 230 by 46.08 gives a result of 5, so 5 of these panels can be wired in Series for
1350 watts per string, and then as many strings in parallel as will produce the maximum output power at the nominal
battery voltage as shown in the table below.
The charging of batteries from a solar array is enhanced by the use of a patented MPPT control design as explained in
detail below.