RC EVOLUTION - 遙控工房 - 香港RC遙控車討論區

標題: DIY tail light [打印本頁]

作者: vrally582 時間: 2006-6-20 06:30
標題: DIY tail light
This circuit diagram is very simple but I dono does it work?

M is motor. D is diode. R is resistor. L is light (LED or no polar LED or bulb)

It won't light up when the car forward. it ll light up when the car reverse.

: 登錄/註冊後可看大圖

作者: dimsim8 時間: 2006-6-20 09:49
because diode won't allow currents flow through when it is reverse biased but when the it in forward biased, it will allow currents to flow through

作者: vrally582 時間: 2006-6-20 10:38

原帖由 dimsim8 於 2006-6-20 09:49 發表
because diode won't allow currents flow through when it is reverse biased but when the it in forward biased, it will allow currents to flow through

yes thatz why i set up in this way. I never try it b4 so I dono it works or not. I will try it on my
junk tin car 1st. I 'd use simple red LED to be break light.But what value of the resistor to use?
Does it also work on 1/10 Tamiya R/C car?

作者: ice1234 時間: 2006-6-20 14:13

原帖由 vrally582 於 2006-6-20 06:30 AM 發表
This circuit diagram is very simple but I dono does it work?

M is motor. D is diode. R is resistor. L is light (LED or no polar LED or bulb)

It won't light up when the car forward. it ll lig ...

It won't light up when the car forward.
It may not be feasible .LED still light up dimmer when car move forward .
When your car move forward ,due to the ESC switching at high frequency and so the motor will generate back emf .So it still have some forward basis current via the diode and light up the led.........
Good try

Try and error is a way for u to achieve your target.....don't give up , keep learning and try.....I also had try this circuit few year ago........HAHA...

Also , what u mean" no polar LED "?? Do u mean it is "two colur led"???

[ 本帖最後由 ice1234 於 2006-6-20 14:24 編輯 ]

作者: vrally582 時間: 2006-6-21 15:32

原帖由 ice1234 於 2006-6-20 14:13 發表

It won't light up when the car forward.
It may not be feasible .LED still light up dimmer when car move forward .
When your car move forward ,due to the ESC s ...

Umm... I dont think so. ESC gen high freq wont become AC current but only high freq DC corrent When move forward or back. The Wave form'd be positive from low freq to high freq : like that ^ ^ ^ ^ to ^^^^^^ but not like that ^V^V^V. This is not a AC motor. In the case of Motor gen Back emf, I think the current giving from power is higher than the current gen from motor's emf. And most emf current'd be eaten by resistor. Unless there is a Cap that is big enough to save this emf energy,it'd happen. (maybe the cap on the motor'd cause that) correct me if i m wrong.

General LED has polar. I bought some LED from XX Street in HK (U should know where it is) that has no polar (I guess it is LED or bulb) One color. It is 3V. Dono 's max current. tell me if u know.

Also, I tried doing this on my tin-car today. It works with no problem. only parall two LED on the motor w/o adding any resister.

作者: ice1234 時間: 2006-6-21 15:50
i only try this on old fashion esc ..........i haven't try this with new band esc...
haha...so i say may be...hehe...
normal one colour led only can light up in one direction.....because it 's also diode....
i know some led can light up in both direction ,but it have two different colour.
Thus ,u find this no polar one should not be led, may be it just a bulb...

作者: ice1234 時間: 2006-6-21 15:51
congratulation

作者: vrally582 時間: 2006-6-22 02:04
The LED installed in my small tin car is gerernal LED. it has + -  polar. Another one I said b4 that has no polar that come with 2 white wires on it. It looks like a LED but more bright than gerenal LED. The store
sales vary color of  these : blue / red/ white.  working Voltage is about 3v.

The car I installed LED is a general toy tin -car . it come w/o ESC and other fancy stuff.  2V voltage to
drive the motor to run. Maybe the same circut using in bigger 1/10 car with ESC. IT need another kind of LED and adding resister. It'd be another story and has another result.

作者: ifrogi 時間: 2006-6-22 10:38
i just got another question is.... when the car running forward. the ESC will give out over 100A to the motor. will it burn the diode?

作者: vrally582 時間: 2006-6-22 12:27
I never use ESC b4. I think if u use a right diode, it wont. U re better to test the max current and
voltage to the motor and choose a right diode. Using higher power diode 'd be safe. 100A
is a very high current. Unbelieveable.

作者: vrally582 時間: 2006-6-22 13:23
I never use ESC b4. I think if u use a right diode, it wont. U re better to test the max current and
voltage to the motor and choose a right diode. Using higher power diode 'd be safe. 100A
is a very high current. Unbelieveable.

作者: ifrogi 時間: 2006-6-22 13:43
yes 100A is huge... I never test the ESC. But it is from ESC spec.
you can have a look. even the cheap TBK-101 ESC has 60A output.
MSC230 has 160A. so if they are real, it is hard to use normal multi-meter to check it.

作者: vrally582 時間: 2006-6-22 15:04
so what is voltage for motor generally?

歡迎光臨 RC EVOLUTION - 遙控工房 - 香港RC遙控車討論區 (https://www.rc-evo.com/xbbs/)