2 possibilities, 1. You have more than 50% charge, 250 kW will slow down to 90 kW and will continue to drop as you reach full charge. When you reach 50% or more charge, 250 kW & 150 kW Supercharger gives about the same output. 250 kW will only save about 5 minutes from 0 to 100%. 2. Detective/over heating supercharger, try another one.
another thing to note is that every 2 Chargers uses the same "conduit" or i don't know what to call it, power source haha. that means anytime someone is next to you charging you are essentially taking from same power source. if the area isn't very busy most people will charge EVERY OTHER charging lot. that's why the charging stations are named 1A then 1B then next is 2A and 2B. another easy way to see this is when someone is charging next to you and they leave, your charging will instantly become faster !
There are a lot of variables that determine max charge rate like your batteries % charge, battery temperature, Supercharger temperature so I wouldn't be too worried that you got 90kw here.
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