SimpliPhi Battery Manual
REV020620
SimpliPhi Power, Inc. | 3100 Camino Del Sol | Oxnard, CA 93030, USA | (805) 640-6700 | info@simpliphipower.com| SimpliPhiPower.com
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discharge. Over-discharging the PHI Batteries will destroy them and Void the Warranty.
In the case where the inverterβs AC Power Output rating exceeds the connected loadsβ actual power draw
(i.e. the inverter is rated at 5 kW but all loads amount to 3 kW of maximum instantaneous power draw),
SimpliPhi still expects that the proper additional precautions be made to ensure that the PHI Battery bank is
not over-discharged. This typically involves the installation of an additional overcurrent protection device
between the PHI Battery bank and the inverter to ensure that the PHI Battery bank does not discharge
beyond its maximum instantaneous power rating. Failure to do so will destroy the PHI batteries and Void
the Warranty.
ππ»πΌ π΅ππ‘π‘πππ¦ π΅πππ ππ΄π ππππ‘πππ’ππ’π πππ πβππππ πππ‘π
=
(
π΅ππ‘π‘πππ¦ ππ’πππ‘ππ‘π¦
)
Γ
(
ππ΄π πΆπππ‘πππ’ππ’π π·ππ πβππππ π
ππ‘π πππ π΅ππ‘π‘πππ¦
)
Example: Two PHI 3.8 kWh-51.2V
nominal
batteries must be installed with an additional 75 ADC-rated
breaker between the battery bank and the inverter.
(
ππ»πΌ π΅ππ‘π‘πππ¦ π΅πππ ππ΄π ππππ‘πππ’ππ’π πππ πβππππ πππ‘π
)
= 2 Γ 37.5π΄π·πΆ = 75π΄π·πΆ
3.2.2 β Sizing for Maximum Instantaneous Charge Rate (DC Coupled)
In a DC Coupled system, the solar PV array output can be mitigated using charge controllers. However,
reducing the solar arrayβs power output using charge controller programming implies that the PV arrayβs
output is also reduced for the entire remainder of the system, including the solar power available for
powering loads and for exporting to the grid. Furthermore, greatly reducing the PV arrayβs output via the
charge controllers effectively wastes the solar PV arrayβs power and puts strain on the charge controllers.
Calculate the minimum quantity of PHI Batteries needed to prevent over-charge from the solar PV array by
considering both the solar array size and the charge controllerβs potential output. Whichever value is less
should be used to size the PHI Battery Bank. If the solar arrayβs maximum potential current output is less
than the paired charge controllerβs Output Amps rating, then the solar arrayβs maximum potential current
output can be used to size the PHI Battery bank. If the charge controllerβs Amp rating is less than the solar
arrayβs maximum potential current output, then the charge controllerβs rating is used to size the PHI Battery
bank.
Divide the systemβs potential charging current by the MAX Continuous Charge Rate per PHI Battery (found
in Table 1.0 or on the relevant batteryβs specification sheet) to calculate the minimum quantity of PHI
Batteries needed to ensure that the solar PV array does not over-charge the battery bank.
Example A: Three PHI 3.8 kWh-51.2V
nominal
batteries (used in a 48-Volt system) must be paired with a
4,500-Watt solar PV array wired to an 80 Amp-rated charge controller. In this case, the 80-Amp charge
controller is used to determine the minimum PHI Battery quantity needed to prevent over-charging from
the solar PV.
πππ‘π‘π = π΄πππ Γ ππππ‘π
4,500 πππ‘π‘ πππππ ππ πππππ¦ = π΄πππ Γ 48 ππππ‘π
4,500 πππ‘π‘π
48 ππππ‘π
= ππ. ππ π΄πππ = ππ΄π πππ‘πππ‘πππ π ππππ ππ πππππ¦ ππ’π‘ππ’π‘