MPPT SET

MPPT SET provides quick setting of the MPPT voltage. Three commonly used solar panel voltage

9V, 12V and 18V are available. Switch one bit of the 4P DIP switch (others remains OFF) according

to the norminal voltage of the panel. To disable the MPPT function, switch the last bit (the OFF bit,

label No. 1) to ON. This bit has the top priority. Once it is at ON, the MPPT function will be disabled

no matter the status of other bits. By disabling MPPT function, The SOLAR IN becomes a buck type

DC-DC Li battery charger

MPPT SET DIP switch

Attention

If the sunlight is too weak, the open circuit voltage of the panel may be below the MPPT voltage. 

The SOLAR IN can not charge the battery under such condition, but users can still turn off the 

MPPT function to continue charging the battery with small current. 

Battery Selection

The battery input BAT IN provides two connectors JST PH2.0 and KF301 5.08mm 2P terminal,

which directly connect each other internally. Usually, connect one 3.7V Li-polymer/Li-ion battery

(4.2V when fully charged) to one of the connectors. The maximum charge current can be up to 2A

for USB IN or SOLAR IN. Safety issue may arise if the charging current exceeds the nominal charge

current of the battery, which is often determined by the capacity and charge rate of a battery. The

maximum allowable charge current of a battery can be calculated with the equation: Maximum

charge current(mA) = Capacity(mAH) * Charge rate(C). Use this equation to check whether the

battery is suitable. For commonly used 1C (charge rate) Li battery, the capacity should be at less

2000mAh. For higher charge rate battery, smaller capacity can be used. Some Li batteries are

packed with battery protection circuit to automatically limit the charge/discharge current. For such

batteries, users are free of worrying about the charge current issue stated above.

DO NOT use nonchargeable battery or chargeable battery not described above.