We receive electrical specifications from German machine builders that list 2 different KW requirements (German & English). Is this because of 50hz vs 60hz?
That could be, based on the skimpy info you have provided. If the machine can run at 60Hz all the motors would speed up by 6/5ths over 50Hz and because HP is a function of speed the horsepower demand would jump, hence multiple kW requirements.
Probably closer to what dpc is saying. I would think it is related to the slight difference in DIN HP vs Mechanical HP. Since the the Mechanical HP can be converter to Watts, (roughly 746W/HP), they are also maybe converting the Metric HP to what they are thinking of as "German" Watts. A "Metric" HP is measured per DIN 70020, a German standard, and refers to the power at a flywheel. Everyone else uses Mechanical HP, which is slightly different. A metric HP is 98.6% of a Mechanical HP. So for converting to kW, 1 metric HP = 0.73549875 kW, while 1 Mechanical HP = .74569987158227022 kW (and for reference, 1 Electrical HP = .746 kW). Usually if it is an electric motor application, they should only be referring to electrical kW, but mechanical engineers can sometimes be fussy that way.
If this is a small machine someone is splitting hairs on you, but if you are speaking of something huge it can make a difference.
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