Orion Jr. BMS Manual
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Rev. 2
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harnesses.
5.) Make sure that all cells are connected to the BMS and that all current is measured by the shunt
current sensor.
It is the user’s responsibility to ensure the BMS is connected to all cells to verify
the BMS has a method to limit current in and out of the pack and to determine and supply the
correct programming parameters (such as maximum cell voltage, minimum cell voltage,
maximum temperature, etc.)
6.) While every effort is made to ensure that the Orion Jr. operates properly under all conditions, it is the
integrator
’s
responsibility to integrate properly into the application such that any failure is a safe failure.
For more information, please read “Failure Modes” in the operational manual.
The integrator is
responsible for the determination of suitability of wire, wiring methods, interconnects, and complying
with any regulations, standards, or codes. The Orion Jr. is not to be used for life support systems,
medical applications or other applications where a failure could cause damage to property or
cause bodily harm or death.
7.) Paralleling separate strings of li-ion batteries together requires special considerations and a method
to isolate each string from each other. One Orion Jr. BMS per parallel string is required.
The Orion Jr.
BMS may not be used with parallel string configurations unless specific external safety systems
are provided. Engineering work by a qualified electrical engineer is required for use with parallel
strings. If you are using the Orion Jr. in a parallel string setup, please see the section about parallel
strings (Note: this is different from paralleling cells inside of a single string which is very common and
can be done with a single BMS.)
8.) Because the Orion Jr. BMS is connected to a high voltage battery pack, hazardous voltages and
hazardous energies may be present inside the unit. There are no user serviceable parts inside the unit
and opening the enclosure or user attempted repairs will void the warranty. Users should never
attempt to repair an Orion Jr. BMS unit. Further, a damaged unit or a unit repaired without authorization
may pose additional safety risks.
DAMAGED UNITS SHOULD BE IMMEDIATELY DISCONNECTED
FROM ALL POWER INCLUDING THE BATTERY PACK AND REMOVED FROM SERVICE. NEVER
CONTINUE TO USE A DAMAGED BMS UNIT.
Please contact the factory or your local distributor for
repair options. Ewert Energy is not liable for damage caused by user attempted repairs or continued
use of a damaged BMS unit.
9.) The Orion Jr. unit is rated for working voltages not to exceed 60 volts DC (48 VDC nominal). The
Orion Jr. BMS may not be used if the voltage between any two points in the battery pack or the
voltage between any 2 pins on the BMS will exceed 60 VDC at any point in time.
Orion Jr. units
may not be used in series to obtain pack voltages above the 60V maximum.
For applications
requiring working voltages above 60 VDC, please consider our standard Orion Jr. BMS.
10.) The shunt current sensor must be installed on the negative side of the battery pack only.
Connecting to the positive side will damage the BMS. Damage from incorrect current sensor wiring is
not covered by warranty.
Orion Jr. BMS Manual
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Rev. 2
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ALWAYS READ THE MANUAL BEFORE USE
The most up to date Orion Jr. BMS manuals can be downloaded at:
www.orionbms.com/downloads
Orion Jr. BMS Manual
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Rev. 2
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Determining which BMS to order
The Orion Jr. BMS is available off the shelf in two configurations
–
with CANBUS and without
CANBUS. Both standard configurations support 1 to 16 cells. In larger volumes, customized versions of
the Orion Jr. unit are available for cost savings including units supporting fewer cells.
Included with the standard BMS
●
Main BMS unit
Optional
●
CANBUS support
●
Shunt current sensor options
●
Pre-assembled wiring harnesses
●
Basic displays, data loggers, and PC interfaces are also options
See “Orion Jr. Purchasing Guide” for details on
ordering options
Orion Jr. BMS Manual
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Rev. 2
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Overview of Theory of Operation
The Orion Jr. protects and monitors a battery pack by monitoring several sensors and uses several
outputs to control charge and discharge into the battery. The BMS measures
inputs from cell voltage
taps, the total pack voltage tap, a shunt current sensor, and thermistors. Using user-programmed
settings, the BMS then controls the flow of current into and out of the battery pack by broadcasting
charge and discharge current limits (via analog voltage references or optionally via a CANBUS) or
through simple on/off digital signals depending on which style is appropriate for the application. The
BMS relies on the user to provide external controls to enforce the current limits set by the BMS to
protect the batteries since the BMS does not have integrated switches. During and immediately after
charging, the BMS will balance the cells using internal shunt resistors based on the programmed
settings.
The Orion Jr. unit monitors each individual cell tap to insure that cell voltages are not too high or too low
(in accordance with the user-programmed values). Using the cell voltages, the amperage going in and
out of the pack (provided by the current sensor), and programmed values in the battery pack profile the
BMS calculates the pack
’s internal resistance, the internal resistance of each cell,
and open cell
voltages. From those calculations, the maximum charge and discharge current limits are calculated and
adjustments are made to the pack’s calculated state of charge i
f necessary. These calculations are also
used in monitoring the health of the pack. Charge and discharge current limits are provided on the
CANBUS or serial bus and can be programmed to trigger on/off digital outputs to allow or deny
charging and discharging of the battery pack.