Customization
Feel free to make adjustments if you find that the dimensions of the Simple Installation
Kit do not accommodate your installation location. You can customize the length of the
pipes by cutting the included pipes or by purchasing additional PVC pipe from your
local hardware store. Be sure to use schedule 40 or schedule 80 PVC pipe. Individual
pipe sections should not exceed 36 inches.
6.
Solar Power & Rechargeable Battery
Solar Power Module & Internal Rechargeable Battery
The Tempest device uses an integrated solar power charge module with four
south-facing (north-facing in the southern hemisphere), vertically-oriented solar
panels. This geometry provides optimal solar charging even in low sun angles at
high latitude locations.
The internal rechargeable battery in Tempest is an LTO (Lithium-titanate) type,
1300mAh battery. This is ideal for use outdoors and in extreme temperatures.
LTO batteries are safe on the environment and have a very long lifetime of
almost 50,000 cycles - which is decades of recharging.
Operation
Your Tempest is shipped with a full battery and
should give you about 2 weeks of
operation without any additional power input, but you should put it in the sun as
soon as possible. Note, it must be powered on in order for battery charging to
occur.
From an empty state, it takes about 4 hours of adequate sunlight (350 W/m2 or
so) on one or more of the four solar panels to reach a full charge. This is a rule-
of-thumb and your mileage may vary. It will charge faster in direct sun but can
still charge slowly with indirect sunlight. As long as your Tempest gets the
equivalent of at least 4 hours of
adequate sunlight every two weeks, it will
continue happily running along. In the event of extended periods of low light
conditions, power management code in the firmware will help your Tempest
operate for as long as possible.
The LTO battery will continue normal charging up to about 113°F (45°C) and
down to about -40°F (-40°C). And the battery will continue providing power well
outside this temperature range for as long as it has a charge - usually long
enough to return to a range where the battery can resume charging again.
Battery Level Indicator
You can check the battery level for your device by viewing the status page for
your station: In the app, go to Settings > Stations > (choose a station) > Status
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