Siemens SITOP solar User Manual page 22

The indication of daily peak performance tells you which maximum PV generator
power was generated on the current day by the device. The indication of this value is
designed as a purely peak value memory so that you will see higher performance as
the nominal performance of your PV generator during the transitional times of year
due to radiation values above 1000 W/m
caused by reflections in cloud layers.
A lower module temperature also contributes to high yields during these times of
year.
Remember that the values stored in the data logger are always the average value
over a 10-minute interval and are thus usually lower values than the peak value.
Specification of the switchon duration of the inverter refers to the current day. The
highest values are naturally achieved during the summer months.
This display shows you the operating time of the device since its first commissioning.
The hours of operation are always incremented when the MASTER is in operation.
Remember that this value can be lost during high electrical interference (e.g., during
a thunderstorm). This may also occur when the voltage of the installed lithium cell
becomes too weak. See also chapter 4.6.1 on replacing the lithium battery.
This display appears when the solar voltage just covers the power consumption of
the inverter. There is no mains supply.
If the solar voltage continues to drop, the device switches off.
Possible causes:
1) Twilight/bad weather: The generated solar voltage of the modules is too low.
2) Good weather: There is probably a defect in the photovoltaic system.
Other actions:
1) No action
2) Please contact your installation technician or distributor. The DC voltage of the
modules and the DC wiring must be checked. If sufficient voltage is applied to the
modules and the wiring is okay, the master inverter may be defective.
Siemens AG C98130-A7580-A1-1-7619
SITOP solar 08/2006
Peak/d 5220 W
2
. Some of these high radiation values are
Time/d 12.3 h
Time/tot 1890h
U-DC too low...
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