Skip to main content

Topic: Big Turtle (Read 5366 times) previous topic - next topic

0 Members and 2 Guests are viewing this topic.

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

______________________________

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.

__________________________
if ($znanje == NULL) {read FAQ; use SEARCH; use GOOGLE; } else { use mozak; make post; }

Odg: Big Turtle

Reply #16
Da, multiju sigurno neces gasit motore u zraku.
Mozda je Tom zato i vidio oktu kak leti na 4 reglera.


Sent from my iPhone using Tapatalk

Odg: Big Turtle

Reply #17
Kruške i jabuke.
Eto - možda i radi - ali zašto? za 20$ esc?


Naveo sam to samo zato da ne ostane mišljenje na forumu da ne radi, kako si prvo bio napisao.

Možda si sam tak slikal - ali svaki motor treba svoj esc. dva brushlessa na jedan esc - no go.
No to je prvi put da čujem da radi.

Dakle zaključak je da radi. Svi učimo dok smo živi.

ako se ne oduzima gas do kraja u zraku i ovaj avio turtle model bu letio vjerojatno bez problema,
a sada kome paše za koji model ili ne to je drugi par rukava.  no moguće je.

npr jasno da auto na tri kotača ne može voziti kao s četiri, ali ne može se reći da nije moguće!
stariji citroen može preći kilometre bez četvrtoga, tj jednog stražnjeg, pošto su prednji širi.
čak i u zavojima.

Citroen GS na trzech kołach

Odg: Big Turtle

Reply #18
Opet bumo došli na batke ;D
Dobro onda bude još vidio, što se tiće reglera vjerojatno kupujem još jedan ili nebum
gasio motore  ;).
Spektrum dx7s i razni modelčeki