Sunway NT 4000 Power Supply User Manual


 
Protection concept The following parameters are monitored
continuously and in parallel by the micro-
controller and displayed on the screen:
· AFI error (ground fault)
· Overheating of the cooling element
· DC overvoltage
· AC undervoltage/overvoltage
In the event of a fault, the conversion is
immediately blocked and the grid relay
disconnected.
In addition, the following protective devi-
ces are provided on both grid and PV
generator side:
· Grid-side varistors
Protect the power semiconductors from
high-energy, time-limited voltage spikes on
the grid and provide for a reduction of
energy in the throttle in the event of grid
disconnection.
· Generator-side varistors
Thermally monitored varistors provide pro-
tection against atmospheric overvoltages
(e.g. due to remote strikes during storms).
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