Should parallel 5kw/10kw surge inverters be able to start HVAC w/o soft start?

[free2enjoy]

Any idea?

 

[RCinFLA]

Surge spec without time duration specification is meaningless.

For A/C compressor you need to support surge load for about 0.5 seconds of duration.

Power factor is another issue. HF inverters don't like poor power factor loads. During startup surge on A/C compressor the power factor can be in the range of 0.2 to 0.4, highly inductive.

 

[free2enjoy]

Thanks. I’ll look into that.

 

[free2enjoy]

Surge spec without time duration specification is meaningless.

For A/C compressor you need about 0.5 seconds of duration for the surge load.

Power factor is another issue. HF inverters don't like poor power factor loads. During startup surge on A/C compressor the power factor can be in the range of 0.2 to 0.4, highly

The inverters user manual just show limits for 102%, 110% and 125% overload. Doesn’t show the surge numbers. It does say loaded motor capability 4hp.

I’m guessing a soft start is smart to have regardless.

 

[sunshine_eggo]

The inverters user manual just show limits for 102%, 110% and 125% overload. Doesn’t show the surge numbers.

Those are effectively the surge numbers.

It does say loaded motor capability 4hp.

It lies. I've seen well pump controllers that say "3hp" but when I get hold of the manufacturer and say, "my 3hp well pump has a 50A surge, will it work?"

"No."

I’m guessing a soft start is smart to have regardless.

Yes.