# Power Industry - How to determine if a transformer is sufficient for the use

If I have a customer who provides me with their peak kW demand (say, 1000 kW) and wants to know if it is sufficient for them to downgrade from a 2500 kVA unit to a 2250 kVA unit.

Is this determination made by simply using the formula kVA=kW/pf Is there any guidance/code/recommendation for how much "room" should be left based on peak demand?

• It would be kW/PF not PF/kW. Don't know more than that as I only know about small electronics Commented Dec 15, 2022 at 17:50
• There is not enough information in the question to make a judgement. Commented Dec 15, 2022 at 19:03
• You also need to know the peak and typical demand. Big transformers can be run at above their rating for short periods, especially in cold weather. Commented Dec 16, 2022 at 13:57
• @SimonB I have 2-years worth of kW records so I know the peak is 1002 kW and typical seems to be about 800 kW Commented Dec 16, 2022 at 13:59
• For a peak demand of 1000 kW to overload a 2250 kVA transformer, the power factor would need to be below .5 - is there any chance to learn PF@peak demand or increase it to saner regions? Commented Dec 16, 2022 at 14:03