Hi Sue!
The conversions are:
30 minutes in a 650-watt would be 19 minutes 30 seconds in a 1000 watt.
60 minutes in a 650-watt would be 39 minutes in a 1000 watt.
Basically, I just took the 10 minute times from the
Conversion Chart from 650-Watt Oven to 1000-Watt Oven and multiplied by 3 and 6.
If you are going to need more times over 10 minutes for 650-Watt to 1000-Watt, let me know ... I will be happy to make you an expanded chart and email it to you.