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BrianG · 01.04.2011, 02:43 PM

Torque (in oz-in) at the motor shaft is derived from 1352/kv*amperage. There are a couple pages at the R/C Calc site that estimates torque.

However, under load, kv does drop due to copper losses. And amperage is dependent on load (gearing/weight/etc). So any calculated value will be approximate. I don't know of anyone who has "dynoed" their BL setups.

By the way, DO NOT EVER purposely stall a motor. When you do that, the rotor isn't turning (obviously), therefore no back-EMF (resistance). The only thing limiting current when you do that is the copper resistance of the wire, ESC, other wiring, and batteries. Theoretically, a 2200kv Castle motor will draw 3700A on 6s under stall. Of course, that won't happen because something will fry.

	(#4)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	01.04.2011, 02:43 PM Torque (in oz-in) at the motor shaft is derived from 1352/kvamperage. There are a couple pages at the R/C Calc site that estimates torque. However, under load, kv does drop due to copper losses. And amperage is dependent on load (gearing/weight/etc). So any calculated value will be approximate. I don't know of anyone who has "dynoed" their BL setups. By the way, DO NOT EVER* purposely stall a motor. When you do that, the rotor isn't turning (obviously), therefore no back-EMF (resistance). The only thing limiting current when you do that is the copper resistance of the wire, ESC, other wiring, and batteries. Theoretically, a 2200kv Castle motor will draw 3700A on 6s under stall. Of course, that won't happen because something will fry.