Power Products SOLAR BOOST 3048 Owner's manual

SOLAR BOOST™ 3048
30A 24/48V MAXIMUM POWER POINT TRACKING
PHOTOVOLTAIC CHARGE CONTROLLER
INSTALLATION AND OPERATION
MANUAL
THIS MANUAL INCLUDES IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
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© RV Power Products, Inc. 2001 430-0013 B

RV Power Products - Solar Boost 3048
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TABLE OF CONTENTS
IMPORTANT SAFETY INSTRUCTIONS ............................................................................. 2
PRODUCT DESCRIPTION................................................................................................... 3
Part Numbers and Options ...................................................................................... 3
OPERATION .................................................................................................................... 3
Current Boost........................................................................................................... 4
Optional Digital Display ............................................................................................ 4
Charge Status Indicator ........................................................................................... 5
Three Stage Charge Control.................................................................................... 5
Bulk Charge ........................................................................................... 5
Acceptance Charge................................................................................ 5
Float Charge .......................................................................................... 6
Two Stage Charge Control....................................................................................... 6
Equalization.............................................................................................................. 6
Disabling Equalization ............................................................................ 6
Optional Temperature Compensation...................................................................... 7
Maximum Power Point Tracking (MPPT)................................................................. 7
How MPPT Works ................................................................................. 8
Typical Current Boost Performance....................................................... 8
Temperature and Output Power .............................................................................. 9
INSTALLATION.................................................................................................................... 9
Over Voltage / Reverse Polarity Protection.............................................................. 9
Electrostatic Handling Precautions .......................................................................... 9
Maximum PV Short Circuit Current and NEC .......................................................... 9
Solar Boost 3048 Setup ........................................................................................... 9
Default Factory Setup ............................................................................ 10
Nominal System Voltage........................................................................ 11
Charge Mode ......................................................................................... 11
Float Transition Current Measurement Shunt........................................ 11
Float Transition Current Setpoint ........................................................... 12
Maximum Power Voltage ....................................................................... 12
Optimizing MPPT ................................................................................... 13
Temperature Compensation .................................................................. 13
Acceptance Charge Voltage .................................................................. 13
Float Charge Voltage ............................................................................. 13
Solar Boost 3048 Installation ................................................................................... 14
Battery and PV Wiring.............................................................................................. 15
Optional Battery Temperature Sensor ..................................................................... 15
Optional External Current Shunt .............................................................................. 16
Optional Digital Display ............................................................................................ 16
Input Power Sources Other Than PV Modules ........................................................ 16
TROUBLESHOOTING GUIDE............................................................................................. 17
SPECIFICATIONS ................................................................................................................ 19
THREE YEAR LIMITED WARRANTY.................................................................................. 19
TABLES AND FIGURES
Table 1 Charge Status Indicator ......................................................................... 5
Table 2 Typical Current Boost Performance....................................................... 8
Table 3 Maximum Conductor Length for 3% Voltage Drop at 24A..................... 15
Figure 1 Front Panel and Remote Display Indicators........................................... 4
Figure 2 Lead-acid Charge Voltage -vs.- Battery Temperature ........................... 7
Figure 3 Setup and Wiring Diagram..................................................................... 10
Figure 4 Detailed Dimensional Drawing ............................................................... 14
Figure 5 Remote Display Cable Schematic.......................................................... 16

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IMPORTANT SAFETY INSTRUCTIONS
1. Refer installation and servicing to qualified service personnel. High voltage is present inside unit. Incorrect
installation or use may result in risk of electric shock or fire. No user serviceable parts in this unit.
2. Remove all sources of power, photovoltaic and battery before servicing or installing.
3. WARNING - RISK OF EXPLOSIVE GASES
a) Working in the vicinity of lead-acid batteries is dangerous. Batteries produce explosive gasses during normal
battery operation.
b) To reduce risk of battery explosion, follow these instructions and those published by battery manufacturer and
manufacturer of any equipment you intend to use in vicinity of battery.
4. PERSONAL PRECAUTIONS
a) Someone should be within range of your voice or close enough to come to your aid when you work near a lead-
acid battery.
b) Have plenty of fresh water and soap nearby in case battery acid contacts skin, clothing or eyes.
c) Wear complete eye protection and clothing protection. Avoid touching eyes while working near battery.
d) If battery acid contacts skin or clothing, wash immediately with soap and water. If acid enters eye, immediately
flood eye with running cold water for at least 10 minutes and get medical attention immediately.
e) NEVER smoke or allow a spark or flame in vicinity of battery.
f) Be extra cautious to reduce risk of dropping metal tool onto battery. It might spark or short circuit battery or other
electrical part that may cause explosion.
g) Remove personal metal items such as rings, bracelets, necklaces, and watches when working with a lead-acid
battery. A lead-acid battery can produce a short circuit current high enough to weld a ring or the like to metal,
causing a severe burn.
5. PREPARING TO CHARGE
a) Never charge a frozen battery.
b) Be sure battery is mounted in a well ventilated compartment.
c) Add distilled water in each cell until battery acid reaches level specified by battery manufacturer. This helps
purge excessive gas from the cells. Do not overfill. For a battery without cell caps, carefully follow manufacturers
charging instructions.
6. CHARGER LOCATION & INSTALLATION
a) Controller employs components that tend to produce arcs or sparks. NEVER install in battery compartment or in
the presence of explosive gases.
b) Protect all wiring from physical damage, vibration and excessive heat.
c) Insure that the controller is properly setup for the battery being charged.
d) Do not expose controller to rain or snow.
e) Insure all terminating connections are clean and tight to prevent arcing and overheating.
f) Charging system must be properly installed as described in these instructions prior to operation.
g) Do not connect to a PV array capable of producing greater than 24 amps of short circuit current @ 25°C.
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RV Power Products - Solar Boost 3048
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PRODUCT DESCRIPTION
Solar Boost™ 3048 is a 30 amp 24/48 volt Maximum Power Point Tracking (MPPT) photovoltaic (PV) charge
controller. Through the use of patented MPPT technology, Solar Boost 3048 can increase charge current up to 30% or
more. Solar Boost 3048’s sophisticated three stage charge control system can be configured to optimize charge
parameters to precise battery requirements based on battery electrolyte type, battery size in amp-hours, and battery
temperature. The system is fully protected against voltage transients, over temperature, over current, and reverse
battery and reverse PV connections. A manual equalize function is also included to periodically condition flooded lead-
acid batteries.
Solar Boost 3048 employs series pass Pulse Width Modulation (PWM) charge voltage control. The advanced
multistage charge control system combined with precise PWM voltage control leads to superior charging and enhanced
battery performance. To provide optimum charge control on installations where battery load varies widely during
charge, Solar Boost 3048 can interface to an external current shunt to provide optimal charge control. Solar Boost 3048
also includes an automatic current limit feature which allows use of the full 30 amp capability without worrying about
overload or nuisance fuse blow from excessive current. The PWM control system uses highly efficient and reliable
power MOSFET transistors. The MOSFET’s are turned on and off at high frequency to precisely control charge voltage
and MPPT. Environmentally sealed high current high reliability relays are used to disconnect the PV array at night to
prevent unwanted current drain. Relays are used rather than blocking diodes for improved power conversion efficiency,
current boost performance, and true reverse battery polarity protection in an MPPT controller. The relays are not
stressed by functioning as part of the voltage control system and continually turning on and off as with other PV
controllers. They simply turn on in the morning and off in the evening, and in this application have a life expectancy in
excess of 105operations.
Since Solar Boost 3048 is a high efficiency series pass “buck” type power converter with current limit, the battery
can be charged from any power source with a voltage greater than the desired acceptance voltage setpoint, and less
than the maximum PV open circuit voltage rating of 127 volts. Examples of this type of use include charge control from
hydroelectric or wind generators, or charging a 24 volt battery from a 48 volt system.
Fully automatic temperature compensation of charge voltage is available as an option to further improve charge
control and battery performance. The available SensorLug™ battery temperature sensor is built for long term reliability.
The sensor element is environmentally sealed and encapsulated into a copper lug which mounts directly to the battery
terminal. A user friendly digital display is also available to monitor PV charge performance. The display may be
provided in the Solar Boost 3048 controller, as a remote panel, or both. The remote panel cable may be up to
300ft/91.4m in length.
PART NUMBERS AND OPTIONS
•SB3048........................... Solar Boost 3048 controller without digital display
•SB3048D ........................ Solar Boost 3048 controller with digital display
•SB50RD25 ..................... SB3048 remote digital display with 25’ cable (standard duplex box mount)
•SB3048PD...................... SB3048D front panel with digital display (add to SB3048 to make SB3048D)
•930-0022-20 ................... SensorLug™ battery temperature sensor with 20’ cable
•CS-100 ........................... 100A/100mV current shunt
•CS-200 ........................... 200A/200mV current shunt
•CS-500 ........................... 500A/50mV current shunt
OPERATION
During installation the Solar Boost 3048 will have been configured to operate in a 24 or 48 volt system, and
for three stage or two stage charge. Additional items which may be configured during installation include;
acceptance and float voltage setpoints, battery amp-hour capacity, temperature compensation and whether full
charge is determined using the internal current shunt or an optional external current shunt.

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Once installed and configured, Solar Boost 3048 charge control and MPPT operations are fully automatic.
Charge turns on whenever the PV array is capable of producing sufficient power. When PV charge is on the Charge
Status LED will indicate the present charge mode, and when PV power production is relatively high, it will show
approximate battery state of charge. At night when PV power production stops, the PV array is disconnected from
the battery to prevent unwanted current drain.
FRONT PANEL AND REMOTE DISPLAY INDICATORS
Figure 1
Note that a minimum battery voltage of 18 volts
in 24 volt systems, or 36 volts in 48 volt systems,
is required for Solar Boost 3048 to operate.
OPTIONAL DIGITAL DISPLAY
An optional digital display is available to monitor PV charge performance. The display is available in the Solar
Boost 3048 controller chassis, and as a remotely mounted panel. Both the chassis display and the remote display may
be installed and used simultaneously. The digital display can be selected to show Battery Voltage, Solar Panel Current,
or Output Charge Current. When the MPPT system is functioning, charge current boost can be seen by noting the
difference between Solar Panel Current and Output Charge Current. If MPPT is not operating, it is normal for Output
Charge Current to show ≈0.1 amps less than Solar Panel Current since the system consumes 100/70mA at 24/48 volts
respectively to operate during charge.

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CHARGE STATUS INDICATOR
An LED charge status indicator is provided both with and without the optional digital display. Indicator function is
identical for the SB3048, SB3048D, and SB50RD.
CHARGE STATUS INDICATOR
INDICATOR
ACTION
CHARGE
MODE
TYPICAL BATTERY STATE
OF CHARGE
OFF CHARGE OFF
(NO PV OR OVER TEMP.)
NOT DISPLAYED
CONTINUOUSLY ON BULK LESS THAN 70% FULL
BLINKING
2 SEC ON / 2 SEC OFF
ACCEPTANCE BETWEEN 70% - 95% FULL
BLINKING
0.2 SEC ON / 2 SEC OFF
FLOAT FULLY CHARGED
BLINKING RAPIDLY
0.2 SEC ON / 0.2 SEC OFF
EQUALIZE N/A
TABLE 1
THREE STAGE CHARGE CONTROL
Solar Boost 3048 is typically configured for a three stage charging process. Acceptance and float voltages are
factory set to approximately 28.6/57.2 volts and 26.6/53.2 volts respectively, which are appropriate for a liquid
electrolyte lead-acid battery at 80°F. As described in the installation section, the most highly optimized charge process
is obtained by using the optional SensorLug battery temperature sensor, and if battery load varies during charge, an
optional external current shunt to determine full charge based on net battery charge current.
Bulk Charge
During the bulk charge stage, the charge status LED will be on continuously. Solar Boost 3048 delivers as much
charge current as possible during bulk to rapidly recharge the battery. In the bulk stage, the battery is typically at a
low state of charge of less than 70% full. Bulk charge is initiated when; 1) Charge current during acceptance or float
increases above the Float Transition Current, or 2) Insufficient power is available from the PV array to hold the battery
at the desired acceptance or float voltage. Maximum available charge current during bulk varies with the number and
size of PV modules installed, available solar energy, and operation of the proprietary MPPT current boosting
system. Electronic current limit prevents the possibility of overload by limiting output current to 30 amps regardless
of available PV input current or input power.
Acceptance Charge
Following bulk charge, the system changes to a constant voltage mode where the acceptance voltage is applied to
the battery. In the acceptance stage, the battery is typically at a high state of charge of between 70% to 95% full.
With installation of the optional SensorLug battery temperature sensor, the acceptance voltage continuously adjusts
to the optimum value based on battery temperature. The graph of Figure 2 shows acceptance voltage as a function of
battery temperature for the factory setpoint of 28.6/57.2 volts @ 80°F. Charge current slowly decreases as the battery
continues to charge at the acceptance voltage. When charge current during acceptance decreases to the Float
Transition Current, typically set to 1.0 amps per 100 amp-hours of battery capacity, the battery is fully charged without
being over charged and the system switches to float.

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Float Charge
Once the battery is fully charged the charge control system switches to the float charge stage. During float charge,
a constant float voltage of 26.6/53.2 volts is applied to the battery to maintain it in a fully charged state without
excessive water loss. The purpose of float charge is to provide a very small charging current to offset self discharge of
the battery. During float charge a healthy lead-acid battery that is fully charged and stabilized will draw approximately
0.1 - 0.2 amps per 100 amp-hours of battery capacity. For example, a typical 330 amp-hour battery will draw
approximately 0.4 - 0.7 amps. If the battery attempts to draw more current than the Float Transition Current, the system
will switch back to acceptance or bulk. Continuous application of a proper float voltage to a fully charged battery will not
harm the battery or lead to excessive water loss.
TWO STAGE CHARGE CONTROL
Certain battery types or system configurations may require two stage charge control. Solar Boost 3048 can be
configured for a two stage bulk-acceptance or bulk-float charging process to accommodate these batteries or systems.
Refer to the Solar Boost 3048 Setup section to configure two stage charge.
EQUALIZATION
WARNING: Not all batteries can be safely equalized.
Equalization should only be performed on vented liquid
electrolyte lead-acid batteries. Follow battery manufacturers
recommendations pertaining to equalization.
Equalization is essentially a controlled over charge and should only be performed on vented liquid electrolyte lead-
acid batteries. Since each cell of a battery is not identical, repeated charge/discharge cycles can lead to an imbalance
in the specific gravity of individual battery cells. Stratification of the electrolyte can also occur. Equalization brings all
battery cells up to the same specific gravity, and eliminates stratification by heavily gassing the battery. Note that the
three stage charge technique matched to battery size, type and temperature provided by Solar Boost 3048 minimizes
the need for equalization, as the battery is properly and fully charged on each cycle.
A proper equalization cycle is a substantial over charging of the battery at relatively high voltages with significant
battery gassing. Solar Boost 3048 features a manually operated equalization function since an operator should always
plan and monitor the process. The operator should ensure that equipment connected to the battery can tolerate the
high equalization voltage which will be applied to the battery, and that the battery attains the proper voltage for the
desired time period. Battery voltage setpoint during equalization will be the bulk voltage plus 2.0 or 4.0 volts for 24 or 48
volt systems respectively. Note that with temperature compensation, the equalization voltage can be quite high at cool
temperatures.
As shown in Figure 1, the equalization push-button is located on top of the enclosure. Equalization is enabled
when the push-button is out, and the Charge Status LED blinks rapidly. Equalization is normally conducted
approximately once per month, with the battery held at the equalization voltage for a period of approximately two hours.
It is best to equalize a battery that is already fully charged so that the desired equalization voltage is reached quickly.
Following the desired equalization period, the equalization cycle is terminated and normal charge operation is resumed
by again pressing the equalization push-button. The battery should then be topped off with distilled water per the battery
manufacturers recommendations.
Disabling Equalization
For certain battery types or electrical systems, it may be desirable to eliminate the possibility of initiating the
equalization cycle. This can be accomplished by gently pulling the red equalization push-button cap off of the equalize
switch and ensuring that the remaining switch plunger is in the normal position. Use needle nose pliers and gently rock
the cap side to side while pulling to avoid damaging the switch mechanism.

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OPTIONAL TEMPERATURE COMPENSATION
The ideal charge voltage required by batteries changes with battery temperature. Temperature compensation
of charge voltage leads to enhanced battery performance and life, and decreased battery maintenance. Fully
automatic temperature compensation can be provided through use of the optional SensorLug battery temperature
sensor. If your system includes this option, the charge voltage setpoints will continuously adjust to the proper value
based on measured battery temperature. Appropriate temperature compensation curves for either lead-acid and
NiCd battery chemistry can be selected. The lead-acid curve for a 24 volt system (12 cells) is –60.0 millivolts/°C or –
33.3 millivolts/°F, whereas the 24 volt NiCd curve (20 cells) is –40.0 millivolts/°C or –22.2 millivolts/°F. These values
double for a 48 volt system. The graph of Figure 2 shows lead-acid charge voltage setpoint vs. battery temperature
for the factory acceptance voltage setting of 28.6/57.2 volts @ 80°F, and float voltage setting of 26.6/53.2 volts @
80°F.
LEAD-ACID CHARGE VOLTAGE SETPOINT -VS.- BATTERY TEMPERATURE
Figure 2
MAXIMUM POWER POINT TRACKING (MPPT)
MPPT and associated current boost operation is fully automatic and will function whenever sufficient PV voltage
and current are available. The percent increase you will receive in output charge current relative to PV array current is
variable, and will change with operating conditions. When conditions are such that sufficient PV voltage and current are
not available to produce an increase in output current, Solar Boost 3048 will operate as a high performance series pass
PWM controller. Current boost performance can be easily monitored using the digital display. Whenever output charge
current is greater than solar panel current, current boost is functioning. A minimum PV current of just under two amps
is required before current boost can begin to operate.
The principal operating conditions which affect current boost performance are battery voltage and PV array
temperature. At constant solar intensity the power available from a PV array changes with array temperature. A PV
array’s power vs. temperature characteristic is such that a cool PV array can produce a higher voltage, and therefore
more power, than a hot PV array. When PV voltage is sufficiently high for MPPT to operate, a constant power output is
delivered to the battery. Since output power is essentially constant while MPPT is operating, a decrease in battery
voltage produces a corresponding increase in charge current. This means that the greatest current increase occurs
with a combination of cool ambient temperature and low battery voltage. Solar Boost 3048 delivers the greatest charge
current increase when you need it most, in cold weather with a discharged battery.
Because output power is constant while boost is operating, anything that leads to lower battery voltage will
produce an increase in output charge current. While a discharged battery is one way to produce lower output voltage,
and therefore higher output current, other normal conditions may produce lower voltage as well. Any 24/48 volt power

Installation and Operation Manual
8
consumption during the day will decrease net battery charge current, which decreases battery voltage. Operating a
large inverter or application of other heavy loads can produce substantial drops in output voltage leading to significant
increases in output current. Additionally, anything that can be done to lower PV array temperature will also lead to
increased charge current by increasing PV power production. Installing modules in a breezy location for example will
cool the PV array due to increased air circulation.
HOW MPPT WORKS
A PV module is a constant current type device. As shown on a typical PV module voltage vs. current curve,
current remains relatively constant over a wide range of voltage. A typical single 75 watt module is specified to deliver
4.45 amps @ 17 volts @ 25°C. Conventional PV controllers essentially connect the PV array directly to the battery
when battery voltage is low. When a pair of 75 watt modules are connected directly to a battery charging at 24 volts, the
modules still provide approximately the same current. But, because output voltage is now at 24 volts rather than 34
volts (2x17V), they only delivers 106 watts to the battery. This wastes 44 watts of available power.
Solar Boost 3048’s patented MPPT technology operates in a very different fashion. Under these conditions Solar
Boost 3048 calculates the maximum power voltage (VMP) at which the PV module delivers maximum power, in this
case 17 volts. It then operates the PV module pair at 2x17 volts which extracts maximum power from the modules.
Solar Boost 3048 continually recalculates the maximum power voltage as operating conditions change. Input power
from the peak power tracking controller, in this case 150 watts, feeds a switching type power converter which reduces
the 34 volt input to battery voltage at the output. The full 150 watts which is now being delivered at 24 volts would
produce a current of 6.25 amps. A charge current increase of 1.8 amps or 40% is achieved by converting the 44 watts
that would have been wasted into useable charge current. Note that this example assumes 100% efficiency to illustrate
the principal of operation. In actual operation, boost will be somewhat less as some available power is lost in wiring,
connections, and in Solar Boost 3048.
TYPICAL CURRENT BOOST PERFORMANCE
As described above current boost performance for a particular installation varies with PV array temperature and
battery voltage. Two of the other primary factors which affect boost performance include system wiring and PV module
design. The effect wiring has on performance is that power wasted heating undersized wiring is unavailable for
charging. This is discussed further in the Battery And PV Wiring section. The effect PV module design has on
performance is that modules with a maximum power voltage (VMP) of 17 volts or higher will tend to produce more
boost, whereas PV modules with VMP less than 17 volts will tend to produce less boost. Additionally, more PV modules
will tend to produce more boost, whereas fewer PV modules will tend to produce less boost.
For a 24 volt system using eight 75 watt PV modules with peak power specifications of 4.45 amps @ 17 volts @
25°C, representative boost performance under a variety of operating conditions is shown in Table 2. Your current boost
performance will vary due to a variety of factors. What you can be sure of is that Solar Boost 3048 will automatically
deliver the highest charge current possible for a given installation and operating conditions.
TYPICAL 24V CURRENT BOOST PERFORMANCE
EIGHT 75 WATT PV MODULES
BATTERY CONDITION
AND VOLTAGE
AMBIENT
CONDITIONS
PV INPUT
CURRENT
OUTPUT CHARGE
CURRENT
PERCENT
INCREASE
FULLY DISCHARGED
21.8V
35°F
EARLY MORNING
8.8 AMPS 12.1 AMPS 38%
HIGHLY CHARGED
27.6V
45°F
CLOUDY, BREEZY
7.9 AMPS 9.3 AMPS 18%
HIGHLY DISCHARGED
23.6V
65°F
CLEAR, STILL AIR
16.7 AMPS 18.4 AMPS 10%
HIGHLY CHARGED
27.6V
75°F
CLEAR, STILL AIR
18.5 AMPS 18.5 AMPS 0%
TABLE 2

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TEMPERATURE AND OUTPUT POWER
Over temperature protection is provided to protect the unit from damage due to high output power at high
ambient temperatures. When mounted vertically as described in the installation section, Solar Boost 3048 can
deliver full output in an ambient temperature of up to 40°C (104°F). If cooling is restricted at high power levels or
ambient temperature is higher than 40°C, the charge control system will cycle on and off, reducing average power
delivery to within safe limits. During periods of thermal shutdown the Charge Status Indicator will display an “off”
condition.
INSTALLATION
WARNING: Read, understand and follow the Important Safety Instructions
in the beginning of this manual before proceeding. The system must be
installed in accordance with local codes and standards. Adjustments or
connections other than those shown in Figure 3 void the limited warranty.
OVER VOLTAGE / REVERSE POLARITY PROTECTION
Solar Boost 3048 is fully protected against reverse polarity and high voltage transients for both the PV array and
the battery. If the battery is connected reverse polarity, Solar Boost 3048 will not operate. If the PV array is connected
reverse polarity, Solar Boost 3048 will not provide output current and the Solar Panel Current display will show negative
current. Should high PV current be available during reverse PV connection the heatsink will become quite warm but no
damage to the unit will result. Note that the unit is not protected against reverse battery connection to the PV terminals.
Damage of this type is not covered under the limited warranty.
ELECTROSTATIC HANDLING PRECAUTIONS
While transient voltage protection is provided for terminal block connections, exposed circuits may be damaged by
electrostatic discharge during installation and handling. Discharge yourself by touching a water faucet or other electrical
ground prior to handling the unit and avoid touching components on the circuit boards. Keep the Digital Display in it’s
electrostatic protective bag until it is installed. All electronic circuits may be damaged by static electricity and these
instructions combined with special packaging are provided to minimize the possibility of damage. The risk of
electrostatic damage is highest when relative humidity drops below 40%.
MAXIMUM PV SHORT CIRCUIT CURRENT AND NEC
To be compliant with National Electrical Code (NEC), solar module controllers should be sized to provide 125%
more rated capacity than the 25°C short circuit current rating of the PV modules, and then all components be sized
another 125% greater. However, Solar Boost 3048 can regularly produce more than 24 amps of output current from 24
amps of input current. The NEC does not cover MPPT type controllers with electronic current limit, but bases the rules
on older less sophisticated controllers which are unable to manage conditions of higher than expected current. Our
interpretation of the spirit of the NEC is that Solar Boost 3048 connected to 24 amps of short circuit PV current, and
branch circuit protection of 40 amps is compliant with the spirit of NEC requirements. This is because the system is
rated for and electronically limited to 30 amps of output current. With wiring and branch circuit protection then rated at
40 amps, the 125% margin is always maintained. The final judgement of acceptability is to be made by the local
authority with jurisdiction.
SOLAR BOOST 3048 SETUP
Solar Boost 3048 has several setup options that need to be configured prior to connection and use. These
selections are configured by setting a single 12 position dip switch on the main circuit board. Refer to Figure 3 for setup
adjustment locations.