General description
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value. The result of the comparison is used to make the decision to change the
working mode from the mains to the inverter.
–
Battery voltage - the value measured at AKK_LEV input determines the process of
charging and discharging the battery. The value is averaged. During battery
operation a signal is needed to indicate a low level of the battery or to protect the
battery. In mains mode this value determines the charger's working mode.
In DC/DC converter voltage the value is not averaged and is used to check if “out” is in
short-circuit state.
During load current the value is measured at PWR_LEV input. The value is needed for
calculating the power of the load (RMS for one period), battery current, overloading.
1.2.6 Communication
The thread of communication is in charge of communication to the PC. This thread
completes the packet from the PC and sends answers. Received packets are interpreted in
the main loop.
1.2.7 SPI
SPI interface is using for communication to EEPROM memory. SPI needs four signals:
MISO, MOSI, SCK and CS. In inactive state all signals are high.
1.2.8 Keyboard
The keyboard contains only one key button connected to BUTTON input active low. The
reaction for this signal depends on the working mode:
Table 12.
Battery state
Battery voltage
BAT_LOW
>=21.75 V (+/- 1%)
L
<
21.75 V (+/- 1%)
H
Table 13.
Working modes
No
Working mode
State
Action
Reaction
OUT_REL
BUTTON L time
OUT_REL
ON/OFF
1
Mains/boost/buck mode
H
Short
No change
H
2
Mains/boost/buck mode
H
Long
Fall to L
H
3
Mains/boost/buck mode
L
Short
Rise to H
H
4
Mains/boost/buck mode
L
Long
Rise to H
H
5
Inverter mode
H
Short
No change
H
6
Inverter mode
H
Long
Fall to L
H
7
Inverter mode
H
Double long
Fall to L
