Phocos ECO-N-T, Руководство пользователя

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The ECO-N-T charge controllers are built to be operated with 12V or 24V vented and
sealed lead acid batteries. A series PWM-charge controller like the ECO-N-T connects
the PV-panel to the battery, to charge it or disconnect it when the battery voltage is high
enough. Depending on the battery voltage it will frequently switch ON and OFF the
charge current to regulate the battery voltage. This voltage depends on the charge site
(Main charge/Boost/Float).
The ECO-N-T will disconnect the PV-panel from battery at night to prevent any current
to flow back from the battery to the panel at night. These functions are acheived by the
use of modern semiconductor switches, called power-MOSFETS. One is used to switch
on/off the charge current, the other one acts as actively switched diode to prevent back
current from flowing from the battery backwards to the PV-panel at night. The output
voltage of these load outputs is the battery voltage.
To protect the battery from getting deep discharged, the charge controller will
disconnect the load output at a low SOC (state of charge). To protect connected load,
the ECO-N-T will also disconnect the load at too high battery voltage levels. This
function is also realized by a power-MOSFET, one for each load output. To acheive
temperature compensation of the charge voltage, the ECO-N-T has an internal
temperature sensor to sense the ambient (battery) temperature. The charge controller
will adapt the charge voltage according to this internal temperature, to provide a charge
voltage compensation of -4mV per degree Celcius and battery cell (24mV/K for a 12V
battery, 48mV/K for a 24V battery).
To provide over-temperature protection functions, it also has a built in temperature
sensor. If the internal temperature gets higher than about 75°C (e.g. at high charge
currents and high ambient temperatures, the charge current will be decreased, to limit
the internal power loss and thus to reduce internal heating. If the internal temperature is
too high, it will also switch off the load current. This shall prevent the charge controller
from being damaged by too high internal temperatures.
This all is realized by the use of a micro-controller inside the ECO-N-T. This micro-
controller is a small computer, equipped with software (firmware) and integrated
peripherals to measure voltages, currents and digital signals, and output digital signal,
to switch on and off transistors, controlling the FETs, LEDs, etc.
ECO-N-T Operational Description