Additional notes for the radian gs8048a, Forcing specific slaves to be active, Nd figure 11 – Outback Power Systems GS4048A Operators Manual User Manual
Page 42: Operation
Operation
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Additional Notes for the Radian GS8048A
The GS8048A has two modules. The modules are controlled individually. The Power Save function
will activate one module at a time, making an additional 4 kW of power available for every load
increase of approximately 2.5 kW.
Figure 11 shows a system of four GS8048A inverters (the master and three slaves) in a parallel system
with a common load bus. The labels at the top indicate the ranking of each unit. The notations at the
bottom show how the units are activated in sequence as loads of approximately 2.5 kW are applied.
The first line shows little load and only the first module in Master is activated.
The second line shows load beginning to be applied. The second module in Master is activated.
The third line shows increasing load. The first module in Slave 1 is activated.
The fourth line shows even higher load. Slave 1 is completely activated.
In general, roughly 5 kW of loads are applied to fully activate an additional slave inverter.
In the example shown in Figure 11, an 8-kW load has been applied, fully activating the first slave.
In this example, loads of approximately 17 to 18 kW would be needed to turn on all inverters.
Figure 11
GS8048A Power Save Priority
Forcing Specific Slaves to be Active:
It is possible to raise the priority of a slave and force it to activate. This is done by setting the master
rank higher than that slave. However, the
Master Power Save Level scale is not the same as the Slave
level.
Slave level settings apply to the whole inverter. Master level settings are applied per module.
This means that increasing the master by one rank will only turn on one additional module. To
completely turn on a slave inverter, the master must be increased two ranks. See the next page.
In Table 4, instead of loads, the number on the far left of each line shows the master increased by one
rank. (This example is otherwise the same as Figure 11.)
The last line of the table shows the master increased to 3, which is the same as the rank of the highest
slave. However, this only activates the first of the three slaves. The master would need to be set to
rank 7 to activate all slaves.
Minimal Load
On
Off
Off
Off
Off
Off
Off
Off
approx. 2.5 kW (12 Aac)
On
On
Off
Off
Off
Off
Off
Off
approx. 5 kW (24 Aac)
On
On
On
Off
Off
Off
Off
Off
approx. 7 to 8 kW (36 Aac)
On
On
On
On
Off
Off
Off
Off
Module 1 Module 2
Module 3 Module 4
Module 7 Module 8
Module 5 Module 6
Master
Master Power Save = 0
Slave 1
Slave Power Save = 1
Slave 2
Slave Power Save = 2
Slave 3
Slave Power Save = 3