Guru
Joined: 13/10/2014
Location: AustraliaPosts: 1770
| Posted: 11:07pm 04 Jun 2023 |
That's difficult to say without a dedicated real time efficiency monitor trying to detect random connector R-Loss effects, it would have to carried out with pure resistive loads across multiple current sets, not going to happen for small R-Loss.
It's not a simple as that, the PD across a resistive connection depends on many variables, the rate of current change, the temperature rise in the connection, current sustained or pulsed, is the connection under physical movement from slight vibrations in the Toriod or choke with suddenly switching loads, the environmental conditions and where the inverter is located, etc.
If you have ever spent time hunting down faults in very high current linear supplies you would have seen this sort of thing a lot, especially as they age. Just looking at waveforms on a DSO may not reveal much.
You could of course, run the inverter up to 7 or 8 kW and use an infra red camera / sensor, or, if you have made your inverter internals easily accessible, you can just feel your way
NOTE: The Startup stall current of equipment like a big compressor varies with:
1:Environmental conditions.
2:Position of the piston in the cylinder at compressor start.
3:Pressure in the tank.
4:Heat in the pump assembly.
5:Point in the AC cycle where the Motor load is dumped across the Inverter.
6:State of Battery Charge.
7:Any variation in R-LOSS across connections when a 27kW input surge is suddenly pulled through it
You can see why measurements at the Limits of Inverter safety vary, you need to plot many readings over time to get a definitive pattern. We do what we can to make meaning out of the limited samples we have, over time a better picture starts to appear, so my interpretation can vary.
These power levels are not something I would want to throw at my Inverter 30 times in a row.
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Edited 2023-06-05 09:09 by KeepIS