Sunny Island 4500
Installation & Operating Instructions
BWRI45-13-EE0304
- 123 -
SMA Regelsysteme GmbH
Fig. 8.12:
Switching behavior when „Kx On tx“ is equal to „Kx Off tx“
Fig. 8.13:
Switching behavior: Exception
•
To control energy sources it is advisable to choose an “On” state that is below
the “Off” state, while in most cases the “ON state should be above the “Off”
state in order to switch loads.
The fact whether the battery state for switch-on is higher or lower than
the battery state for switch-off determines when a relay is actually
switched.
As described above there are two different modes: “Consumer type“
(switch-on limit is above switch-off limit) and “Feeder type“ (switch-on
limit is below switch-off limit). If the same battery state is set for both the
switch-on and the switch-off limit the relay is controlled as for the “Con-
sumer type“ as also shown in Fig. 8.12.
If the same values have been entered under the parameters “7xx_Kx t2 begin“ and
“7xx_Kx t2 end“ a simple setting to a battery state-dependent control of this relay has
already been finished. Often, however – especially in island grids supplied by PV –
an operating mode is desired where the devices are controlled depending on the bat-
tery state, but additionally also depending on the time of the day. To this end it is
possible to define a second time period (“special time period t2“, lasting from “7xx_Kx
t2 begin“ to “7xx_Kx t2 end“, see also Fig. 8.14. For this second period, battery states
