Technical description
MT150PP, MT230PP, MT350PP, MT550PP
EN
18
6.2
LED indicators
6.3
Battery charging function
The charging characteristics for fully automated continuous operation without monitoring are
referred to as IU0U characteristics (see charging curve in fig.
1: I phase (Constant current phase)
At the beginning of the charging process, the empty battery is constantly charged with the maxi-
mum charging current (100 %). The charging current decreases when the battery has reached a
state of charge of 75 % (90 % for lithium batteries). Batteries with a voltage of 0 V are charged with
reduced charging current until the battery voltage exceeds 9 V.The duration of the I phase
depends on the state of the battery, the load from the consumers and the state of charge. For safety
reasons the I phase is terminated after a maximum of 15 h (in case of battery cell defects or similar).
2: U1 phase (Constant voltage phase)
The U1 phase starts when the battery is fully loaded. The charging current is reduced. During the
U1 phase, the battery voltage is kept constant at a high level. The duration of the U1 phase
depends on the battery type and the depth of discharge.
LED
Status
Description
Batterie/n voll
On
Batteries fully charged (100 %); U2 phase
Lights dimly
Charging process in U1 phase
Off
Charging process in I phase
>80%
On
High charge (80 – 100 %)
Laden
On
Charging current present, brightness indicates the
intensity of the charging current
Flashing
Battery protection:
• High temperature protection
• Low temperature protection
Flashing once
Over voltage protection
Standby
Flashing
Standby mode
Schwach
(only MT 150 PP,
MT 230 PP)
On
Low voltage at the house battery
AES/RE
(only MT 350 PP,
MT 550 PP)
On
Excess solar power, “AES/RE” terminal is activated
Off
No excess solar power, “AES/RE” terminal is inactive
