PIKA B801 REcharge User manual

Pika B801 REcharge™
Off-grid Charge Controller
Operation Manual

OperationManual
B801BidirectionalREbus™BatteryChargeController
Revision Table
Revision
Date
Changes
1.0
03/19/2015
Initial Release

1
General Remarks
Congratulations! You have purchased the Pika Energy B801 Bidirectional REbus™Charge Controller, a
dependable, efficient component of your clean energy system. The B801 is the result of thePikateam’s
careful development and testing, building on decades of experience in the fields of power electronics
and renewable energy systems.
The B801 is a charge controller designed for high-efficiency bidirectional conversion between a REbus™
Microgrid and a 24V to 48V battery bank. This charge controller is equipped with a small fan to keep
things cool under extreme conditions. An illuminated display and intuitive system of menus enable you
to configure a variety of setpoints as well as view the energy output of every component of your
renewable energy system. The charge controller also serves as an information gateway, enabling
monitoring and control of your entire renewable energy system.
Unlike conventional charge controllers,whichonlyconnecttoonetypeofenergysource,Pika’sB801is
designed to operate as the hub for an expandable network of renewable energy devices, based on the
REbusTM renewable energy standard.
What is REbusTM?
The underlying technology behind Pika’s B801 charge controller is an innovative energy management
technologyor‘smartmicrogrid’calledREbus™.REbus™isaDCenergynetwork that enables customers
to build cost-effective, scalable renewable energy systems. The REbusTM network is designed to serve as
an open interconnection standard for networking next-generation energy technology – like Wi-Fi or USB
for green energy!
IMPORTANT! Only REbusTM compatible components may be used in connection with this charge
controller. Do not connect the output of a PV array or any other non-REbusTM electrical source to the
charge controller terminals. Serious property damage and/or personal injury may result.

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Contents
Revision Table ............................................................................................................................................... 0
General Remarks ........................................................................................................................................... 1
1 Regarding this Document ......................................................................................................................... 4
1.1 Symbols used in this document .......................................................................................................... 4
1.2 Data Label ........................................................................................................................................... 4
2 Important safety information and instructions ......................................................................................... 5
2.1 Appropriate Usage .............................................................................................................................. 5
2.2 Supported Battery Types .................................................................................................................... 5
3 Notes concerning installation and operation ............................................................................................ 6
3.1 Intended (normal) use ........................................................................................................................ 6
3.2 Pika Energy Factory Limited Warranty ................................................................................................ 6
3.3 Service ................................................................................................................................................. 6
4 The REbusTM Microgrid ............................................................................................................................... 7
4.1 Simple and Efficient Power Distribution and Management ............................................................... 7
4.2 Integrated Power Line Carrier (PLC) Communications ....................................................................... 7
4.3REbus™ControlProtocol(RCP) ........................................................................................................... 7
5DesigningaREbus™System ....................................................................................................................... 8
6. User Interface............................................................................................................................................ 8
6.1 Overview of User Interface ................................................................................................................. 8
6.2 LED Displays ........................................................................................................................................ 8
6.2.1Multicolor“REbus™”LED ............................................................................................................. 8
6.2.2Multicolor“Battery”LED ............................................................................................................. 8
6.2.3Blue“Wi-Fi”LED ........................................................................................................................... 9
6.3 LCD Display .......................................................................................................................................... 9
6.3.1REbus™SystemPage.................................................................................................................... 9
6.3.2 B801 Charge Controller Page ..................................................................................................... 10
6.3.3 Wi-Fi Status Page ....................................................................................................................... 14
6.3.4OtherREbus™DevicePages ...................................................................................................... 15
6.3.5 Background Illumination ............................................................................................................ 16
7 Operation ................................................................................................................................................. 16

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7.1 Installation ........................................................................................................................................ 16
7.2 Power Switch .................................................................................................................................... 16
7.3 Enable/Disable .................................................................................................................................. 16
7.4 Charging Stages ................................................................................................................................. 16
7.4.1 Terms ......................................................................................................................................... 16
7.4.2 Bulk............................................................................................................................................. 17
7.4.3 Absorption.................................................................................................................................. 17
7.4.4 Float ........................................................................................................................................... 17
7.4.5 Equalize ...................................................................................................................................... 17
7.5 Battery Voltage Limits ....................................................................................................................... 18
7.5.1 Low Battery Voltage ................................................................................................................... 18
7.5.2 Error Low Battery Voltage .......................................................................................................... 18
7.5.3 High Battery Voltage .................................................................................................................. 18
7.6 High Temperature Operation ............................................................................................................ 19
7.7 Configurations ................................................................................................................................... 19
8 Internet Compatibility .............................................................................................................................. 22
8.1 Wi-Fi Antenna ................................................................................................................................... 22
8.2 Configuring your Wi-Fi Connection ................................................................................................... 23
8.2.1 Scan-based network setup ......................................................................................................... 23
8.2.2 Add network setup ..................................................................................................................... 24
8.3 Wi-Fi Status Messages and Troubleshooting .................................................................................... 25
8.3.1 Connection states: ..................................................................................................................... 25
8.3.2 Connection state messages: ...................................................................................................... 26
8.4PikaaccountandtheREview™onlinemonitoringsystem ............................................................... 27
9 Maintenance ............................................................................................................................................ 28
9.1 Battery Maintenance ........................................................................................................................ 28
9.2 Handling Errors and Faults ................................................................................................................ 28
10 Troubleshooting Guide .......................................................................................................................... 28
11 Frequently Asked Questions .................................................................................................................. 30
12 Specifications ......................................................................................................................................... 31

4
1 Regarding this Document
This manual contains important instructions for the B801 Charge controller that must be followed during
installation and maintenance of the charge controller. The B801 is designed with safety in mind, but as
with all electrical and electronic equipment, certain precautions must be observed when installing
and/or operating the B801. To reduce the risk of personal injury and to ensure the safe installation and
operation of the B801, you must carefully read and follow all instructions, cautions and warnings in this
user manual.
Store this manual so that it is always easily accessible.
1.1 Symbols used in this document
WARNING: This indicates a fact or feature very important for the safety of the user to
prevent injury or death and/or which can cause serious hardware damage if not
applied appropriately.
CAUTION: Presents information to prevent damage to this product
EARTH GROUND SYMBOL
1.2 Data Label
A permanently affixed label indicating the device specifications, serial number, and manufacturing date
is located on the bottom surface of the charge controller enclosure. Tampering with the label can void
warranty.

5
2 Important safety information and instructions
IMPORTANT SAFETY INSTRUCTIONS
SAVE THESE INSTRUCTIONS
This manual contains important instructions for model B801 that shall be followed during installation
and maintenance of the Pika B801 Charge controller.
WARNING: Before installing the Pika Energy B801 Charge controller, read all instructions and
caution markings in this manual and on the B801 as well as on other REbus™devices.
WARNING: Electrical installation in the United States shall be done in accordance with all local
electrical codes and/or the National Electrical Code (NEC), ANSI/NFPA 70.
WARNING: Electrical installation in Canada shall be done in accordance with all local electrical
codes and/or the Canadian Electrical Code.
2.1 Appropriate Usage
The B801 is a charge controller designed for high-efficiency bidirectional conversion between a REbus™
DC Microgrid and a 24V to 48V battery bank. Refer to the charge controller installation manual for
detailed information about the product and its intended use. The charge controller may only be
operated with REbus™ devices. Do not use the charge controller for purposes other than those
described here. Alternative uses, modifications to the charge controller or the installation of
components not expressly recommended or sold by the manufacturer void the warranty claims and
operating permission. Contact Pika Energy technical support if you need clarification regarding proper
use of the charge controller.
2.2 Supported Battery Types
The B801 is to be connected to a 24V to 48V battery bank, contact Pika support for information
regarding other battery voltages. Supported battery chemistries include: flooded lead acid, sealed lead
acid(“maintenancefree”),AGM, NiFe (Nickel-Iron), aqueous hybrid ion and lithium based chemistries.
Lithium-based chemistries including Li-ion, lithium polymer and lithium-iron phosphate may require
individual balancer circuits and special setpoint adjustments. Contact Pika Energy before using the B801
with Lithium-based battery chemistries.

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3 Notes concerning installation and operation
3.1 Intended (normal) use
Your charge controller is strictly constructed according to approved safety requirements. Improper use
may lead to lethal hazards for operators and/or damage to devices and property. Improper use or
modification of the B801 may result in serious property damage, personal injury or death.
REBUS™ INPUT ONLY! The B801 is designed to accept regulated direct current (DC) from REbusTM-
compatible devices (e.g. REbusTM-compatible wind turbine, REbusTM-compatible PV Link unit). DO NOT
CONNECT PHOTOVOLTAIC MODULES DIRECTLY TO THE REBUS™ INPUTS OF THE B801 CHARGE
CONTROLLER. DOING SO WILL VOID THE WARRANTY AND MAY DAMAGE THE CHARGE CONTROLLER.
Any use other than the specified intended use shall not be deemed intended or normal use, and may
result in property damage, personal injury or death. Pika is not liable for damage or injuries caused by
unintended use.
Damage caused by unintended use is at the sole risk of the operator.
“Intendeduse”shallalsoincludeadherencetotheoperatingandinstallationinstructions.
Your trained and authorized installer must obtain all necessary permits and agreements from your local
government and your utility company for a legal and code-compliant installation of your REbus™Smart
Microgrid system. See the User Manual for more detail.
3.2 Pika Energy Factory Limited Warranty
The Pika limited warranty covers defects in workmanship and materials of the Pika B801 Charge
Controller for a period of five (5) years from the date of original purchase of such charge controller at
point of sale to the originally-installed end user location. Contact Pika Energy Support for warranty
claim information.
3.3 Service
WARNING: Do not attempt to repair the B801 Charge Controller. The charge controller contains
no user-serviceable parts.
If the Pika B801 malfunctions or fails in any way, first contact Pika customer service at 1 [phone]
for troubleshooting help. See the Warranty section for details on terms and conditions for repair or
replacement under warranty. You must obtain an RMA (Returned Merchandise Authorization) number
prior to returning the unit. Obtain the assistance of a skilled and qualified installer to safely disconnect
the charge controller for shipment.
Technical Support Information:
Support department hours: 9AM to 5PM EST, Monday – Friday (excluding holidays)
Phone: [phone] United States Language: English
Email: [e-mail]

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4 The REbusTM Microgrid
The REbusTM Microgrid is the underlying technology that allows for the efficient and robust
interconnection of different types of renewable energy products. This section is informational only and
not required knowledge for operation of your Pika B801 Charge controller.
4.1 Simple and Efficient Power Distribution and Management
The REbusTM Microgrid architecture was designed with renewable energy in mind. A clean-sheet
approach to power distribution resulted in the most practical and efficient interconnection technology
available. The REbusTM Microgrid operates at variable voltage in a defined band, between +/- 180-200 V
relative to ground which simultaneously allows for efficient power transmission, reduced shock hazard,
and simplified electronics for a bidirectional converter such as the B801. The variable voltage
communicates energy availability to the attached REbus™ devices, which allows for prioritized energy
storage and load shedding. The REbusTM Microgrid is designed to support many different types of
renewable energy sources and power converters, as well as accommodating future 380VDC REbusTM
Microgrid loads that are presently in development.
4.2 Integrated Power Line Carrier (PLC) Communications
The REbus™ Microgrid standard also specifies an optional power line carrier communication technology
that enables devices on the same REbus™Microgrid to communicate with one another. The B801 uses
this capability to gather information about your system such as the status and energy production of your
Pika T701 Wind Turbine or your solar array, which connects to the REbus™ Microgrid through the Pika
S2001 PV Link.
4.3 REbus™ Control Protocol (RCP)
REbus™ Control Protocol (RCP) is a communications protocol developed specifically for the transfer of
data between REbus™-compatible power converters and data management products. RCP is an open-
standard protocol which enables independent developers to interface with REbus™ products and create
software and applications to enhance user experience. Please visit the Pika Energy website to learn
more about RCP and the software applications that are currently available.

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5 Designing a REbus™ System
Your trained and qualified installer will work with the Pika Energy technical support team to design the
right system for your site. Please consult with Pika Energy sales department at [phone] or on the
web at http://www.pika-energy.com to find an installer near you.
The Pika Energy product system is designed from the ground up for unmatched flexibility. First and
foremost, the B801 Charge controller accepts input from any combination of REbus™-compatible
sources. In fact, the B801 supports up to 32 devices on the REbus™ Microgrid network, and the
automatic power management capability of REbus™ ensures that excess input power from renewable
sources such as the Pika T701 Wind Turbine or Pika S2001 PV Link will be throttled back to prevent
over-charging of the batteries. As of publication, Pika Energy offers the following REbus™productsin
addition to the B801 Charge Controller:
T701 Wind Turbine
S2001 PV Link
X3001 Inverter
REport Data Monitor
Check the Pika Energy website at http://www.pika-energy.com for the latest selection of REbus™ -
compatible product offerings.
6. User Interface
6.1 Overview of User Interface
The B801 Charge Controller user interface is accessible via the LCD on the front cover. It is designed to
provide basic information such as power, energy and battery voltage. Adjustable setpoints for the B801
and attached REbusTM devices can be changed from the LCD screen as well.
6.2 LED Displays
The B801 user interface is equipped with three LEDs to quickly offer information about the status of the
charge controller and other REbusTM devices.
6.2.1Multicolor“REbus™”LED
Thisgreen/yellow/redLEDindicatesthe statusof theREbus™microgrid and attached devices. When
solid green, all devices are functioning normally and are generating power. When solid yellow, devices
are functioning normally but there is no power input from the REbus™microgrid. When red, one or
more of the REbusTM devices are in an error state and require attention before operation will continue.
AredlightcouldalsoindicateafaultwiththeREbus™Microgriditself(e.g.agroundfault). See the LCD
Display for more information about the specific fault that has been detected.
6.2.2Multicolor“Battery”LED
This green/yellow/red LED indicates the status of the B801 itself. If the B801 is Disabled (or powered
OFF), the Battery LED will be OFF. The Battery LED will only be illuminated if the B801 has been Enabled.

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When solid green, the B801 is functioning normally and is importing or exporting power to/from the
REbus™ DC Microgrid. Blinking green indicates a state where the B801 is functioning normally but not
importing or exporting power to/from the REbus™ DC Microgrid. When solid yellow, the B801 is in a
“Waiting”state,nopowerisbeingimported/exportedandnouserinputisrequired. After a timeout
hasexpiredtheB801willexit“Waiting” state and resume normal operation. When solid red, an error
with the charge controller has been detected and user attention is required before the unit will resume
operation. See the LCD Display for more information about the specific error that has been detected.
Blinking red is displayed during an equalization cycle which is initiated by the user. Reference Section
6.3.2 for a table of Error! Reference source not found..
6.2.3Blue“Wi-Fi”LED
This blue LED is illuminated when a connection to a Wi-Fi router has been established and is operating
normally. The blue LED is OFF if no Wi-Fi connection has been established.
6.3 LCD Display
The LCD displayprovidesaccesstoinformationabouttheB801andotherconnectedREbus™devices.
The display is organized into pages with three default pages and one additional page for each attached
REbus™device. Each device page allows the user to enable/disable the device. Additionally, user
adjustable setpoints can be accessed using the LCD display.
6.3.1REbus™SystemPage
TheREbus™System PagegivesanoverviewoftheentireREbus™DC Microgrid (displays voltage and DC
power). This is the default page of the display and appears automatically on power up.
Position
Description
Explanation
A
REbusTM DC
Power
The instantaneous power being generated by REbusTM sources. This is the
amount of power being input into the REbusTM side of the B801.
B
Bus Voltage
The voltage of the electrical bus that connects all of the REbusTM devices to the
B801. The normal range is 340 to 410 Volts.

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C
REbus™
Device
Error
Notification
This message is displayed when a REbusTM device reports an error. The
message indicates which REbusTM device requires your attention.
D
REbusTM
Status
Indicator
LED
This LED describes the state of all of the REbusTM devices connected to the
REbusTM DC Microgrid. The LED will be RED if one or more REbusTM devices are
reporting an error, YELLOW if no power is being imported/exported, and
GREEN if power is being imported/exported from the REbusTM DC microgrid.
The color of the LED does not depend on the page that is currently displayed.
E
User Input
buttons
These five buttons allow the user to scroll through display pages and
command connected devices as well as the B801.
Button functionality when in a menu:
Left
Right
Exit menu or cancel menu selection before
confirmation.
Advance to see menu options
Up/Down
Change menu selection. Selected item will be
highlighted.
Center
Select current highlighted menu item
Button functionality for REbusTM Information Page
Left/Down
Scroll to the Wi-Fi information page.
Right/Up
Scroll to the B801 information page.
Center
No functionality on the REbusTM information page.
6.3.2 B801 Charge Controller Page

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Position
Description
Explanation
A
B801 Status
The B801 displays its name and status at this location. Possible status
messages:
Powering up
The B801 is powering up.
Disabled
The B801 has been disabled by the user.
Waiting
The B801 is waiting for a short period of time before
energizing the REbusTM DC Microgrid.
Bulk Charging
Battery
The B801 is importing power from the REbusTM DC
Microgrid to bulk charge the batteries.
Absorption
Charging Battery
The B801 is importing power from the REbusTM DC
Microgrid to complete the charge cycle on the
batteries.
Float Charging
Battery
The B801 is importing power from the REbusTM DC
Microgrid to maintain a complete charge on the
batteries.
Standby
The B801 will display this message when it is waiting
for power to be generated by your REbusTM devices.
Discharging
Battery
The B801 is exporting power to the REbusTM DC
Microgrid.
Equalize Charging
Battery
The B801 is performing an equalize cycle on the
batteries as initiated by the user.
ERR: General
An unspecified error has occurred. Please contact
Pika Energy for assistance.
B
DC Power,
battery
voltage and
Energy
display
The B801 displays the instantaneous power being imported/exported
to/from the batteries as well as the current battery voltage. It also tracks the
amount of energy that has been exported overall.
C
Battery Status
LED
This LED provides an indication for the status of the B801 which is
independent of the page that is currently displayed.
Battery Status LED Color
Solid Yellow
Waiting
Blinking Green
Standby (Enabled but no power is currently being
imported/exported)
Green
Enabled and importing/exporting power
Red
The B801 has reported an error and requires your
attention
Blinking Red
Equalize charging cycle is in progress
Off
The user has disabled (or turned OFF) the B801

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Button functionality for battery charge
controller information page
Left/Down
Scroll to the REbusTM information
page.
Right/Up
Scroll to the device information
pages.
Center
Open the battery charge
controller menu.
Menu Options:
Enable/Disable
Instruct the charge
controller to enable or
disable.
Settings
Adjust setpoints for B801
Configuration of the B801 can be done from the Charge Controller page. Always configure the B801
before Enabling it. Press the center button to access the various options for the charge controller.
From here, use the arrows keys to navigate. The B801 may be “Enabled” or “Disabled” and user
adjustable setpointsmaybeenteredbyselecting“Settings”andthen“Modify”.
A brief message may be displayed while the setpoints load.
Once the setpoints are loaded, use the up and down arrow keys and press the center button to change a
desired setpoint. When the bar turns solid, the setpoint is ready to be changed using the up and down
arrow keys.

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Holding the up or down button for 5 seconds will increment the setpoint much faster. Refer to Table 1
User Setpoint Table for a description of each setpoint as well as permissible ranges. Only after pressing
“Commit”willallofthe setpoints be saved. NOTE that changing the numberofcells(“Batt Num Cell”,
setpoint #4) or the battery chemistry type(“Batt Type”,setpoint #3) will automatically default the
ENTIRE setpoint table after selecting commit. Any alteration to battery chemistry or number of cells in
the setpoint table will cause the remainder of the table to default to different values. If making changes
to battery chemistry or number of cells, commit changes and re-enter the settings menu from the B801
device page before configuring the rest of the setpoints as described below.
To save time during initial B801 configuration, follow the steps below:
1. Navigate to settings fromtheB801devicepage,select“Modify”.Thisbringsupthemenutoeditthe
setpoints.
2. Select the correct battery type and number of cells (according to Table 1 User Setpoint Table)
3. Commit battery type and number of cells (scroll to bottom of menu, select “commit” and press center
button)
4. Re-navigate to settings from the B801 device page, select“Modify”and configure all other B801
setpoints
5. Committhesetpointsbyscrollingtothebottomofthemenu,selecting“commit” by pressing the
center button.

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6.3.3 Wi-Fi Status Page
Position
Description
Explanation
A
Wi-Fi network
and IP address
The B801 displays the Wi-Fi network and IP address that it has been
assigned when configured to connect to a Wi-Fi network.
B
Wi-Fi Status
The B801 also displays the Wi-Fi connection status when configured to
connect to a Wi-Fi network. The B801 will also print the reason for a
failed connection. See section 8.3 Wi-Fi Status Messages and
Troubleshooting for descriptions of the connection status messages
and troubleshooting information.
C
Wi-Fi activity
LED
This blue LED will flash when the B801 is communicating on a Wi-Fi
network.
D
Wi-Fi settings
not configured
This message is displayed when the B801 has not been configured to
connect to a Wi-Fi network, or after the Wi-Fi settings have been reset
from the Wi-Fi menu.
Button functionality for Wi-Fi Information Page
Left/Down
Scroll to the device information
pages.
Right/Up
Scroll to the REbusTM information
page.
Center
Open the device menu.
Menu Options:
Setup
Set the Wi-Fi configuration
settings.
Reset
Reset the Wi-Fi configuration
settings and connection.

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6.3.4 Other REbus™ Device Pages
Position
Description
Explanation
A
REbusTM Device
Name, Type,
Status
The B801 will display the name, device type, and status of each of the
REbusTM devices.
B
REbusTM Device
DC Power and
Energy
The B801 also displays the instantaneous DC power being generated (or
used) by this device. The total and daily amount of energy generated is
also displayed.
C
Error State
Message
When the device is in an error state, the B801 will display the error
status here. Statuses are device-specific so please refer to the manual
for REbusTM device for descriptions of the status messages and
troubleshooting information.
D
Error Indication
Icon
This icon provides an indication that this device needs attention.
E
REbusTM Status
Indicator LED
This LED describes the state of all of the REbusTM devices connected to
the REbusTM. The LED will be RED if one or more REbusTM devices are
reporting an error, YELLOW if no REbusTM devices are functioning
normally but are not generating power, and GREEN if all REbusTM
devices are functioning normally and generating power. The color of the
LED does not depend on the page that you are looking at.
Button functionality for Device Information
Page
Left/Down
Scroll to either the next REbusTM
device if there are more to view,
or the Wi-Fi settings page.
Right/Up
Scroll to either the previous
REbusTM device if there are more
to view, or the charge controller
information page.
Center
Open the device menu.
Menu Options:
Enable/Disable
Instruct the charge
controller to enable or
disable itself.
Remove
Remove this device from
the display. Only useful for
clearing devices that you no
longer have attached to the
REbusTM.

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6.3.5 Background Illumination
The background light is typically turned off to conserve power, however, any time a button is pressed
the background light will turn on to help illuminate the display. The background light will automatically
turn off after 30 seconds of inactivity.
7 Operation
7.1 Installation
Please consult the Pika B801 Charge Controller Installation & Service Manual for instruction and
important safety precautions related to the installation of your new charge controller. Anyone installing
a B801 Charge Controller should follow the strict safety procedures and instructions provided in the
Installation & Service Manual.
7.2 Power Switch
The power switch located on the bottom of the charge controller and can be used to turn your B801 ON
and OFF. High voltage may still be present inside the charge controller and at the terminals even
when this switch is in the OFF position. Note that disconnecting the battery bank (e.g. via a service
disconnect or circuit breaker) may not turn the charge controller off if sources (e.g. wind or solar) are
providing power to the REbus™ DC microgrid. Always check for voltage on each terminal before
performing any electrical service!
7.3 Enable/Disable
Enable
To permit the B801 to import and export power while connected to the batteries, it must be enabled.
Once enabled, the B801 will automatically return to importing and exporting power after an outage
(power cycle or battery disconnection). To “Enable” the B801, navigate to the B801 page, press the
centerbutton,select“Enable”fromthemenuoptionsandselectconfirm. The“disabled”statemessage
will no longer be displayed on the B801 page.
Disable
To prevent the B801 from importing and exporting power while connected to the batteries, it must be
disabled. Once disabled, the B801 will not import or export power until it has been enabled. To disable
theB801navigatetotheB801page,pressthecenterbutton,select“Disable”fromthemenuoptions
and select confirm. The“disabled”statemessagewillbedisplayedontheB801page.
When disabled but powered up, the B801 will remain connected to your local wireless network and still
operate as a communications gateway for the REbus™ DC Microgrid.
7.4 Charging Stages
7.4.1 Terms
Terminology used in the description of the operation of the B801 is defined below.

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Depth of Discharge (DoD)
The state of charge of the batteries can be 0% to 100% charged. The Depth of Discharge refers to how
much of the total charge you want to use before charging the battery bank back to 100% charge again.
For example a 40% DoD would mean that when the batteries got down to 60% state of charge then the
B801 would start to Bulk charge the batteries back to 100% state of charge (see Bulk charging section for
more information on Bulk charging). In order to get the most out of your batteries every charge cycle
you want to discharge them as much as possible. However, the lifetime of the batteries decreases as
the DoD gets larger. Research your battery model specifications and assess your energy production and
usagetomakethechoicethat’sright for you.
7.4.2 Bulk
Bulk charging occurs when the batteries are between the desired DoD and fully charged. During this
stage the battery voltage rises to the ”Bulk Voltage”andthe battery bank voltage is held atthe“Bulk
Voltage” for a set amount of time.Afterthevoltageisheldatthe“BulkVoltage”forthesetamountof
time the B801 enters the Absorption charge stage.
7.4.3 Absorption
Asthebatteriesnearacompletecharge,lessandlesscurrentisrequiredtomaintainthesame“Bulk
Voltage”. Absorptionchargingmaintainsthesame“BulkVoltage”asthebulkchargingstatewhile
tapering down the amount of current into the batteries. After an allotted time has elapsed the current
will have decreased significantly and charging will then enter Float charging stage, at this point the
batteries are near a 100% charge.
7.4.4 Float
Float charging starts when the battery is close to a full charge, the B801 attempts to apply a constant
float voltage, maintaining a near 100% charge. If the battery loads are consuming more power than the
input power coming from the REbus™ DC Microgrid, then the battery voltage will decrease. When the
battery voltagereachestheuserdefined“Re-bulk” voltage, the B801 will enter Bulk charging mode
again. The B801 will always cycle through the three charging states: Bulk, Absorption and Float.
7.4.5 Equalize
After the battery bank experiences repeated charging cycles the individual cells that make up each
battery become unbalanced, and some hold more charge then others. In order to maximize the lifetime
and total energy storage of your battery bank you must “Equalize” the battery bank. Equalization brings
all of the individual cells within a battery to the same voltage. This is done by holding the battery bank
at a slightlyhighervoltagethenthe“BulkVoltage”.Thisdoesnot harm the batteries in any way and it is
part of typical battery maintenance. Equalization is initiated manually by the user and stops after the
equalization time has elapsed. It is recommended to perform equalization periodically and during a
time with steady input power. Please check with the battery manufacturer about maintenance and
equalization best practices.