PV*SOL Expert 6.0 - Manual - Valentin Software

Factor = 45 for roof or façade-integrated modules without ventilation space
System Check
This gives, for example, an offset of +9°C on the external temperature for modules with
ventilation space, and a minimum irradiation of 300 W/m².
If under Options/Settings/System Check you select Set Values, you can enter
temperature and irradiation extremes, which are then used in the system check.
The module array’s MPP voltage is calculated for both of the working points described
above, and then compared with the inverter’s MPP tracking range.
A message warning of discrepancies appears if the inverter’s threshold values vary by
more or less than 10% from the modules. A value over 50% less than the lower MPP
threshold is not permitted.
Overstepping the upper MPP threshold is restricted at the next stage by the strict
observation of the maximum no-load voltage.
Upper Voltage Threshold Check
The inverter’s maximum system voltage must not be exceeded on any account. Exceeding
the inverter’s upper voltage threshold can cause irreparable damage to the inverter.
The maximum occurring voltages should be checked very carefully.
As a comparative value PV*SOL ® defines the module array’s no-load voltage at the working
point: minimum module temperature and maximum irradiation. This point has already
been calculated for the MPP voltage check (see: MPP Voltage Check).
A message that the critical voltage has been reached appears if the module array’s no-load
voltage equals the maximum inverter voltage.
You are able to continue with simulation, but you should take into account when
planning your system, that exceeding the maximum inverter voltage can cause
irreparable damage to the inverter.
Exceeding the maximum voltage by 25% is not permitted.
The following checks are made on stand-alone systems:
Stand-Alone System Inverter AC Output Check
For AC appliances the inverter’s nominal AC output and the appliances’ maximum output
are compared to ensure that the inverter can deliver the maximum output for the
appliances.
Without a back-up generator, a message appears if the inverter output is less than 98% or
greater than 120% of the appliances’ maximum output. Outputs less than 33% and greater
than 500% of the appliances’ maximum output are not accepted.
If a back-up generator is used, this is able to cover the consumption directly, ie the backup
generator’s energy does not flow through the stand-alone system inverter. The upper
threshold remains the same, but the programme does not strictly set the lower threshold.
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