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Hi everyone,
Do you have any idea of the duration of compressors inrush current ? I know (from this post: https://community.victronenergy.com/questions/4454/peak-power-of-victron-inverters.html) that a Multi/ Quattro can hold 200% the nominal current for 600ms (30 cycles - 50Hz).
But how long does an inrush peak current last?
I ask this question because in my sizing, I am 70% over the quattros nominal capacity during the inrush current.
Thanks in advance.
There's no single answer. It will depend on the type of motor and the circuitry placed in front of it. You might be able to talk to your manufacturer, but more likely, you'll have to test it yourself.
You're powering a huge compressor with this inverter. It would make more economic sense for you to buy the right size of inverter for the steady-state demand, and then add a soft-start capacitor to reduce the inrush demand as you test and find it necessary.
Hi Ben,
Thanks for your answer. I kind of expected this answer... But is there any order of time ? Is it more like microseconds, milliseconds or seconds ?
Unfortunately, I can't test it. A customer asked me to size a system and I don't know the compressors models.
It is not just one compressor, there's AC and some resistive load, with an average power factor of 0.9 if everything start together which is OK good.
But if most of the compressors start together, the quattros will be over load during these inrush current.
The inrush current curve is complex and will have different (larger) values in each of those timeframes you mention, typically.
How many ACs do you have? Where did you get the inrush number you are using to arrive at 170% of capacity?
In this set-up, I've got these inductive loads :
I took a factor 4 for the AC inruch current and 3 for the pump, I've got these numbers from the tables on the internet.
