AEG PV.500-MH Manuel D’Utilisation

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Protect PV.500_MH Operating Instructions 
 
80000043212 BAL 
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If the DC voltage continues to increase due to the sun's rays get-
ting stronger and the mains voltage and mains frequency are with-
in acceptable limits, a start-up attempt is made. During a start-up 
attempt, the inverter stack is switched on, thereby drawing power 
from the DC voltage that is present. Inverter output contactor K7 is 
open during a start-up attempt. If the load on the DC voltage caus-
es it to collapse too dramatically during this start-up attempt, the 
inverter stack is switched off again and there is a delay until the 
next start-up attempt is made. If the DC voltage does not dip too 
significantly, inverter output contactor K7 closes and power is fed 
into the mains. The inverter is now in the "Operation" status. 
Day: 
During the course of the day, the inverter will remain in the "Opera-
tion" status if the sun's rays are strong enough and no faults occur. 
Power is fed into the mains and inverter output contactor K7 is 
closed. 
Evening: 
As the sun goes down, the power fed into the mains decreases. If 
this power falls below a certain value for a certain time, the operat-
ing conditions are no longer met. The inverter stack is switched off, 
inverter output contactor K7 opens and the unit switches to the 
"Waiting" status. 
Once the "Waiting" status delay has elapsed, the unit switches 
back to "Waiting for feed conditions". Although the sun's rays are 
not as strong, the DC voltage might still be high enough for a suc-
cessful start-up attempt with the inverter stack and inverter output 
contactor K7 being switched on again. However, because the 
sun's rays are not as strong, it is unlikely that the operating condi-
tions will still be met in the "Operation" status. As a result, the 
equipment will switch back to the "Waiting" status once a delay 
has elapsed.  
When the unit switches back to this status, the delay is extended 
until the unit switches back to the "Waiting for feed conditions" sta-
tus. 
The cyclic changes of status "Operation" -> "Waiting" -> "Waiting 
for feed conditions" -> "Operation" can take place several times 
depending on insolation, the time of year, location and other condi-
tions (e.g. snow on the PV cells). So that inverter output contactor 
K7 is not overloaded by this cycle of changes, the "Waiting" status 
delay is extended every time the unit switches to this status. 
This has very little effect on the energy fed in, because the low 
levels of insolation mean that hardly any energy is being generat-
ed. 
Later in the evening: 
Levels of insolation continue to fall. As a result, the DC voltage 
drops again. If the DC voltage drops below a certain value for a 
certain time, no more start-up attempts are made. If the DC volt-
age continues to drop, the unit switches to the "Night" status. 
Night: 
The equipment shuts down all possible loads so that as little ener-
gy as possible is being consumed. The equipment remains in the 
"Night" status until the following morning.