Odg: Big Turtle
Reply #15 –
Kruške i jabuke.
Moguće je zavrtiti dva motora na jedan esc - očito. Ali to je pokretanje na zemlji bez vanjskih utjecaja na motor.
Ajmo se vratiti na model aviona. Startaš na zemlji, poletiš, spustiš gas na 0 - motori se slobodno vrte (od propa - nema kočnice) - i pokušaš ponovo startati. Šansa da motori nisu u syncu međusobno je ogromna. Esc upogoni jedan - drugi blokira ( to ste sigurno čuli i na jednomotornom modelu - izrazito pištanje) i kaj dobijemo (ako nisi ODMAH spustio gas) - dvomotorni model koji leti na jednom motoru - ravno u zemlju - i/ili spaljeni ESC (iz blokiranog motora ga utuče back EMF).
Eto - možda i radi - ali zašto? za 20$ esc?
I kopija sa Castle sitea
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1. Two motors can run on a single controller -- but:
a. They must be very closely matched -- within 1% or so on Kv 1. If they are not perfectly matched, timing from the controller is AVERAGED between the difference on the two motors (this happens because the back-EMF voltages average when the wires are paralleled on the motors.) 2. This will cause higher surge currents to the motors-- and will tend to increase the temperature of the controller and motors.
b. They will not always start correctly
1. If they don't start correctly (for example, one motor starts, and the other does not) the controller can be damaged.
2. So, if two motors are run, they must be started on the ground, and there should be no attempts at restart in the air -- AND if one motor fails to start, the power should be shut down immediately.
So, my personal recommendations are that:
1. We recommend using two controllers to run two motors.
2. If the user runs two motors on a single controller, the controller should be derated by 30% (for example, a 45 amp controller should be used in an installation which draws no more than 31 amps on both motors
combined.)
3. If two motors are run on a single controller, the motors must be the same type and wind, and must be well matched.
4. The motors should be started on the ground, and not restarted in the air.
5.High inertia loads (for example, large props on very small motors through gearboxes) shouldn't be attempted in a dual motor installation.
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