Is wattage rating of a VFD split between 3 phases?

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Gary25

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I've been asked to complete an electrical load list with the watts required for each phase of a 3Ph, 400A, 11kW VFD. The VFD is feeding two motors with a total load of 21A. How many watts for each phase?
 
The most accurate way is to just scroll through the menu and interrogate the VFD for the phase currents when it's running and work out the power in Watts from those. Some drives will even give you apparent power and real power figures.
 
I would say that 21A sounds about right, that would equate to an apparent power of 14.5kw (4.83kw on each phase)

Of course if not fully mechanically loaded, you'dd draw less power and you could follow marvo's advice to look at the data from the VFD.

It all depeneds on what you want to know and for what purpose as to whether you want actually maximums, or general real world figures
 
Thanks for your feedback Marvo and Phoenix, it's very much appreciated.

What you've both said makes perfect sense, unlike my original post, which should have said 400V AC not 400A.

The VFD isn't installed yet. I think the requirement is to give the customer a general idea of what to expect. I had initially thought it might just be a straightforward 11kW divided by 3, i.e. 3.67kW per phase, but then started to have doubts.
 
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