BZ PRODUCTS MPPT250 User manual

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.

A unique feature of the MPPT250 is the 100 ma 13.8 volt trickle charger. The purpose of the trickle
charger is to maintain full charge on the engine/generator starter battery. The low charge current will keep
engine start batteries fully charged without using water. Operation is fully automatic and transparent from
other charging circuits.
SYSTEM PLANNING: Carefully plan your installation. Determine fuse ratings, wire size and solar panel
input voltage. Install the MPPT250 near the battery bank. Avoid installing the controller in wet, damp or
small confined locations. Do not install the MPPT250 in direct sunlight. Use short direct wiring. Install the
controller in accordance with state, local and national electrical codes. Securely fasten the controller to a wall
or other suitable structure. Provide support for all wiring. Place the battery temperature sensor on or near the
battery. Install properly rated fuses.
WIRING: Use high quality stranded wire only. Solid wire is not recommended. The MPPT250 wire
connector will accept up to # 12 wire. A short length of #12 wire may be spliced into a larger size wire. See
wiring diagram for more details.
Protect wiring from damage. Clearly labeling all wiring with permanent wire markers will simplify
installation and help prevent wiring errors. Write the wire designations on the MPPT250 wiring diagram.
Documenting the installation will help troubleshoot any problems in the future. Permanent wire labels are
available from most electrical parts suppliers. Route wiring as directly as possible to the PV panels and
batteries. Take care to follow the wiring diagram exactly.
WIRE SIZING: For best operation use properly sized wire. Refer to the wire size chart to determine
minimum wire size. Both solar panel and battery circuits should use the same size wire. Wire sizes specified
are minimum required , a larger wire size than specified may be used
WIRE SIZING CHART
USE CAUTION WHEN CHANGING FUSES
FUSES: Separate fuses are required for the solar panel, main battery, low voltage disconnect and auxiliary
battery circuits. Use properly rated fuses in all circuits. See wiring diagram for more information.
FUSE RATINGS: Properly rated fuses are required in all installations. Refer to the fuse selection chart and
wiring diagram to determine the proper fuse ratings.
TOTAL 0-10 FT 11-20 FT 21-30 FT 31-40 FT 41-50 FT
0 TO 100 # 10 AGW # 8 AWG # 6 AWG # 4 AWG # 2 AWG
101 TO 250 # 8 AWG # 6 AWG # 4 AWG # 2 AWG # 1/0 AWG

BATTERY AND SOLAR PANEL FUSE CHART
BATTERY TEMPERATURE SENSOR: Position the battery temperature sensor on or near the main
battery. If the main battery is in a non-heated location, place the battery temperature sensor outside of the
heated area that the MPPT250 is installed.
FLOAT VOLTAGE CALIBRATION: Battery float voltage is pre-calibrated to 14. 1 volts.
In most installations the float voltage needs no adjustment. Check battery manufacturers
specifications for proper float voltage.
To adjust the battery float voltage locate the float voltage control on the rear of the MPPT250. Let
the battery charge up to 14.1 volts ( the red float LED will light ) before adjusting the float control. Adjust
the float voltage counter clockwise to lower the float voltage and clockwise to increase the voltage. Adjust
the float control in small increments until the desired voltage is displayed on the MPPT250 volt meter. In
order to properly charge the battery over a wide temperature range, the battery float voltage is temperature
compensated. Battery voltage will be higher in cold temperatures and lower in warm temperatures. Secure
battery temperature on or near the main battery.
BOOST CURRENT: The solar panel produces higher output voltage than the battery voltage. This higher
voltage, the maximum power point voltage is wasted with conventional PWM solar controls. The MPPT250
electronically converts this higher solar panel voltage into higher battery charge current. This is referred to as
boost current. Highest boost current occurs when the battery voltage is low and the solar panel is cold.
Advanced microprocessor control and high efficiency power converter circuitry combine to produce
the highest boost current possible over a wide range of conditions. Depending on conditions boost current
may be as high as 30%. Current boost in the 20% range is common.
SOLAR PANELS: Ideally all of the solar panels in the system should be of the same type and
power rating. The MPPT250 works equally well with mixed solar panels. The microprocessor control
determines the operating point of the solar panels that produce the highest charge current to the battery. See
wiring diagram (last page) for solar panel wiring configurations. Maximum input power is 250 watts and
minimum recommended input is 68 watts.
SOLAR PANEL VOLTAGE: The advanced microprocessor control of the MPPT250 allows a
higher input voltage from the solar panels to charge a 12 volt battery. In many installations higher boost
current over a greater operating range may be achieved by wiring the solar panels in series to produce a 24
volt PV input to the MPPT250. 100 volts maximum PV input voltage for model MPPT250HV. Nominal
12 volt solar input performs very well too. See wiring diagram (last page) for solar panel wiring
configurations.
DO NOT EXCEED THE MAXIMUM SOLAR POWER OF 250 WATTS
MPPT250 WIRE CONNECTION ORDER: Connect the MPPT250 wiring in the following order (failure
to follow exact order could result in damage to the control). If used ,connect the auxiliary battery charger and
low voltage disconnect circuits to the appropriate terminals on the MPPT250. Connect battery + and - to the
MPPT250. The LCD display and the yellow Low Voltage Disconnect led will turn on. Connect the solar
panel + and - to the MPPT250. In a few seconds the controller will turn on and begin charging the battery.
PV VOLTAGE 12 VOLTS UP TO 100 WATTS BATTERY & PV FUSE RATING 10 AMPS
PV VOLTAGE 12 VOLTS 100 TO 250 WATTS BATTERY & PV FUSE RATING 30 AMPS
PV VOLTAGE 24 VOLTS UP TO 150 WATTS BATTERY FUSE 20 AMPS PV FUSE 10 AMPS
PV VOLTAGE 24 VOLTS UP TO 250 WATTS BATTERY FUSE 30 AMPS PV FUSE 15 AMPS

MAINTENANCE: The MPPT250 requires little maintenance. Clean the MPPT250 with a damp cloth.
Recalibrate float voltage if required. Visually inspect the entire system for damage. Tighten any loose
connections. Keep the photovoltaic array clean and properly aligned to the sun. Keep batteries clean. Follow
battery manufacturers maintenance recommendations.
WARRANTY: BZ PRODUCTS, INC. Model MPPT250 is warranted to be free of defects in material and
workmanship for five years from the date of purchase. Failure to provide correct installation, operation or
care for this product, in accordance with the instruction manual, will void the warranty. Product liability
shall be limited to repair or replacement, at the discretion of the manufacturer. The manufacturer is not
responsible for the labor or other charges necessitated by the removal, transportation, or reinstallation of any
defective product. Warranty does not cover damage due to, mishandling, abusive conditions, lightning, or
exposure to weather. No specific claim of merchantability shall be assumed or implied beyond what is
printed in this manual. No liability shall exist from circumstances arising from the inability to use this
product, or it’s inappropriateness for any specific purpose. In all cases, it shall be the responsibility of the
customer to insure a safe installation in compliance with local, state and national electrical codes.
RETURN PROCEDURE: To return a model MPPT250 for warranty service provide the following
information. Name/Company name, return address, daytime phone number, description of failure, copy of
the sales receipt. Include $14.00 for return shipping and handling.
BZ PRODUCTS, INC.
7914 Gravois Road. St. Louis MO 63123 USA 314-644-2490
[email protected] www.bzproducts.net
MPPT250 /MPPT250HV SPECIFICATIONS:
PV charge current 25 amps continuous Digital meter 1/2” LCD display
Surge current 35 amps 10 min. DC volts range 0-99.9 volts ± .5%
Array voltage open circuit 50 volts open circuit DC current range 0-99.9 amps ± .75%
Input power max 250 watts Batt. Temp. comp. -18mV/°C nominal
Input power min 68 watts PV input voltage 12 or 24 volts nominal
PV input voltage auto ranging Reverse current . 01 amps nominal
Min battery voltage 10 volts Battery capacity 100 AH minimum
Operating temp. -20 to + 60°C Storage temp. -30 to + 70°C
Float voltage range 12.5 to 15.5 volts Weight 2 pounds
Operating current .15 amps nominal Float regulation ± .05 volts nominal
Wire size # 12 max. AWG Mounting four # 6 screws
Efficiency >95% @ 20 amps Finish black powder coat
Float voltage 14.1 volts Aux. batt. charger 13.8 volts @ .1 amp max.
Lightning protection MOV 1000 watt Size 7.8” X5.1” X2.5”
LVD current 15 amps max. LVD current 20 amps surge
LVD disconnect 12.0 volts LVD reconnect 12.6 volts
100 volts maximum PV input for model MPPT250HV.
An optional enclosure is available for the MPPT250/MPPT250HV.
Specifications subject to change without notice.
12/08

MPPT250 REAR VIEW
SOLAR PANELS
68 TO 250 WATTS
12 TO 48 VOLTS
PV -
BATTERY +
BATTERY -
AUXILIARY BATTERY +
LVD -
+ -
+ -
BZ PRODUCTS, INC.
MPPT250 WIRING DIAGRAM V 3.0
OPTIONAL LOAD
ON/OFF SWITCH
BATTERY FUSE 9"
FROM BATTERY
AUX BATTERY FUSE
9" FROM AUX. BATTERY
LOW VOLTAGE DISCONNECT
FUSE 20 AMPS MAX
9" FROM BATTERY
PV FUSE
PV +
- +
LOAD 15
AMPS MAX
AUX.
BATTERY
12 VOLTS
1 AMP
FLOAT VOLTAGE
CONTROL
#12 WIRE SPLICE HEAVIER WIRE
SEE WIRE SELECTION CHART FOR WIRE SIZES
*
*
SEE FUSE SELECTION CHART
FOR RECOMMENDED VALUES
*
20 AMP
A SHORT LEINGH OF #12 WIRE
CONNECTED TO THE MPPT250.
AS REQUIRED.
+ + + + +
+ +
- -
--
- - -
PV -
PV +
MIXED SOLAR PANELS
230 TOTAL WATTS 12 VOLTS
50W
50W
90W 90W
50W
64W
64W
MIXED SOLAR PANELS
228 TOTAL WATTS 24 VOLTS
PV -
PV +
MAIN
BATTERY
12 VOLTS
+ -
12 AND 24 VOLT PV WIRING COMBINATIONS FOR MPPT250 ONLY.
MPPT250HV INPUT PV VOLTAGE 12 TO 48 VOLTS. 100 VOLTS MAXIMUM.
MAXIMUM PV INPUT POWER 250 WATTS.
WIRING AUX BATTERY CHARGER
AND LVD ARE OPTIONAL.