BZ PRODUCTS, INC.
INSTALLATION MANUAL
VERSION 3.0
MODELS MPPT250
™
and MPPT250HV
™
CURRENT BOOSTING MAXIMUM POWER POINT SOLAR CHARGE CONTROL
For best battery charging performance with Model MPPT250, configure the solar panels
for 24 volts nominal.
CAUTION! READ ALL INSTRUCTIONS PRIOR TO
INSTALLING OR USING THIS EQUIPMENT.
SAFETY INSTRUCTIONS: Refer service to qualified service personnel.
Incorrect installation may
result in risk of fire. Remove all sources of electrical power, photovoltaic and battery before servicing this
equipment. Never charge a frozen battery. Warning! Batteries produce explosive gasses. Install batteries in a
well ventilated area. Follow battery manufactures maintenance and charging recommendations. Install
properly rated fuses as required. Do not connect controller to generators or alternators.
DESCRIPTION:
The model MPPT250 is a 25 amp high performance current boosting solar control.
Through the use of advanced microprocessor control and high efficiency power converter, power wasted in
older PWM style solar controls is converted into higher charge current. The MPPT250 allows for input
voltage conversion. This increases the Maximum Power Point voltage and allows for higher boost current
over wider operating conditions. The MPPT250 is designed to charge 12 volt batteries only.
A high accuracy digital volt and amp meter displays battery voltage and charge current. An
auxiliary 100 ma 13.8 volt trickle charger is provided to keep the engine/generator start battery fully charged.
A 15 amp capacity low voltage disconnect protects the battery from over discharge conditions. Proper
battery charging is maintained over a wide temperature range with the battery temperature sensor. Battery
float voltage is accurately regulated. Night time battery discharge is eliminated through the use of a high
efficiency Scotkey diode. Maximum input power to the MPPT250 is 250 watts.
OPERATION:
During operation the MPPT250 may feel warm. Operation of the MPPT250 is fully
automatic. No adjustments are required for most installations. When power is available from the solar panel,
the MPPT250 microprocessor measures and determines the optimum operating point of the solar panel to
produce the highest charge current possible to the battery. There is no interaction between the MPPT250 and
other battery charging systems.
The float voltage of the MPPT250 is calibrated to 14.1 volts. When the battery voltage reaches 14.1
volts the red float LED turns on. At this point, charge current to the battery will gradually diminish to
maintain the 14.1 float voltage. As soon as a load is turned on, maximum charge current is applied to the
battery. Battery temperature compensation adjusts the float voltage to properly charge the battery over a
wide temperature range. When the battery is warm the float voltage will drop and when the battery is cold
the float voltage will rise. MPPT250 is well suited for flooded, deep cycle and gel type batteries.
A low voltage disconnect is used to protect the battery from excessive discharge by automatically
turning off a load. The load is disconnected when the battery voltage is 12.0 volts or lower. When the
batteries are recharged to 12.6 volts the low voltage disconnect reconnects the load. The yellow LED on the
face of the MPPT250 is lit when the load is connected. Operation of the low voltage disconnect is fully
automatic. Maximum low voltage disconnect load current is 15 amps.
Do Not
connect the low voltage
disconnect to inverters.
