See Heater <name> not heating at expected rate
This is not a setting you usually determine. This is a Klipper sanity check to make sure the hardware works as expected, i.e. your heater is actually heating up.
All regular heater that I know or have dealt with during support activities can usually cope with Klipper’s default settings.
If your heater is really that weak, you might want to add
[verify_heater extruder]
check_gain_time: 40
If it craps out anyway, then you should consider changing it.