Figure 21 Output Protection, Short Circuit With No Fuse; Figure 22 Output Protection - Short Circuit With Fuse - ABB 827E Product Manual

Figure 21 Output Protection, Short Circuit with no Fuse

Figure 22 shows two inverters running when a short circuit is applied in a circuit protected by a fuse.
The output voltage is on Ch1, and two of the output inverter currents are on Ch4 and Ch3.
The Inverters clear the fuse within a few cycles and then the output voltage returns. Note that the
inverter output currents are load sharing after the short is cleared. A fuse or circuit breaker trip time
will shorten as more inverters are present in the system. Trip-time curves for circuit breakers and
fuses are usually found in their datasheets. Use 28 amps per inverter (short circuit current) to
determine the trip-time from the datasheet curve.

Figure 22 Output Protection - Short Circuit with Fuse

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