OMD10078 rev F
10
1.2.2 Overload management
Inverter can provide continuously 100% of nominal load and can tolerate overload
conditions up to 125% for 10 minutes or 150% for 1 minute.
Peak conditions such as take-off of engines or magnetic parts are managed limiting
the output current to 200% for 5 cycles, then reducing to 125%.
Any times output power grows above 100% the inverter keeps feeding the loads,
while the microprocessor activates the “thermal image” algorithm to calculate the power
overload based on the output current and duration of the overload.
User loads are powered by inverter output up to the end of maximum allowed time,
then the static switch transfers the load to the emergency line without interruption of
output power.
Picture 6 – Thermal image characteristic
Picture 7 – Overload with bypass available
1) BYPASS AVAILABLE
As soon as an overload is
detected the algorithm starts
to calculate the increment of
the energy.
When the threshold value is
reached the load is
transferred to bypass.
To allow a safe cooling of the
components (IGBT’s,
transformer) the inverter is
switched off for 30 minutes.
When this time has elapsed
the inverter is switched on
again and the load
transferred back to the
primary supply.
