SunSaver MPPT Installation and Operation Manual

4.0 OPERATION

4.2 TrakStar

MPPT Technology

The SS-MPPT utilizes Morningstar’s TrakStar Maximum

Power Point Tracking technology to extract maximum power

from the solar module(s). The tracking algorithm is fully

automatic and does not require user adjustment. Trakstar

technology will track the array maximum power point voltage

) as it varies with weather conditions, ensuring that

maximum power is harvested from the array through the

course of the day.

Current Boost

In many cases, TrakStar MPPT technology will “boost” the

solar charge current. For example, a system may have 2

Amps of solar current owing into the SS-MPPT and 5 Amps

of charge current owing out to the battery. The SS-MPPT

does not create current! Rest assured that the power into

the SS-MPPT is the same as the power out of the SS-MPPT.

Since power is the product of voltage and current (Volts x

Amps), the following is true*:

(1) Power Into the SS-MPPT = Power Out of the SS-MPPT

(2) Volts In x Amps In = Volts Out x Amps Out

* assuming 100% efficiency. losses in wiring and conversion exist.

If the solar module’s V

is greater than the battery

voltage, it follows that the battery current must be

proportionally greater than the solar input current so that

input and output power are balanced. The greater the

difference between the maximum power voltage and battery

voltage, the greater the current boost. Current boost can be

substantial in systems where the solar array is of a higher

nominal voltage than the battery as described in the next

section.