RC India

RC Equipments => Electric Power => Topic started by: roopeshkrishna on December 29, 2011, 07:26:22 PM



Title: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:26:22 PM
Friends.., some of my Friends were in anger with me, as i stopped posting about the circuit and details of E S C s and related stuffs..and also getting lots of personal requests..answering to all individually is not easy..so i am posting all of my proved circuits and stuffs..proved..for years..and my team is winning lots of competitions in various segments...all we know only a few among us are capable of following high density electronic circuits, and in practical means, so we must consider all modelers,and here i am sharing some of my stuffs, that can compete by anyone, who only need some interest and time...oh..yes..with some good coffee...

so all we know, once again, we must need a basic radio controlling unit for our modeling. previously buying a radio set was almost far beyond reach of an average modeler..but now even the high brands are offering some good radios for value for money. a good 4 channel radio is enough for a beginner..but a 6 channel is preferred as it will be a benefit to you later...
so, most of the modelers now uses a second battery pack for the RX in the craft..it increases extra weight and will be space consuming..especially for a small craft it will be a mess..so we starts from a B E C...B E C..?  yes all we hear about B E C, over the E S Cs.we know B E C, is Battery Eliminator Circuit..is yes this unit reduces the battery voltage to our specific needs...here for us is 4.8 volts to 6 volts. most standard reputed company radio Rxs are based on 6 volts as you can see the battery box provided with a Futaba radio set. is a battery box is capable of holding 4 dry cells each rated at 1.5 volts..so total 6 volts..but my experience and study shows most cheap class servos starts to emit a kooorrrrr noise as we fed it with 6 volts..so a 4.8, or 4.4 more clearly is enough for Rx unit,as most of the input circuits works on 3.3 volts..

so, here i am starting with a B E C, is a basic need of any modeler..then will follow through the simple electromechanical  E S C s, then full electronic, and advanced, in to BLDC...

we need a standard servo wire, can purchase, or can take from a scraped servo...the color codes as red is battery +, yellow is Signal, and Brown is Gnd. or battery -.in some other companies red will battery +, black will be battery -, and white will be signal..so follows...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:28:05 PM
now collect some vero boards, from any electronics shop...
and some appropriate heat sinks...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:30:52 PM
now buy a 7805 voltage regulator, for4.6 volts and 6 volts for 5 4 volts...
as this regulator is only capable of driving around 600 mAh safely, we must add a power driver to it to cope with additional loads..
we can add M J E 13005, or M J E 3055 for this purpose, but only using up to 2 servos..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:32:45 PM
we need two electrolytic capacitors in to 470 micro farad, with a voltage of 25 to 35 volts..must be a good quality one...

shows the pin configuration of the voltage regulator...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:34:46 PM
we need two diodes, and must use a transistor insulator kit, to isolate the transistor from heat sink..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:37:30 PM
fix the power transistor to the heat sink...
solder it as shown..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:40:22 PM
solder the regulator, as shown that the out put pin directly attached to the base of the PT...
follow the diagram..and solder it as well..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:45:26 PM
attach two of the capacitors as in the diagram...
attach an L E D with a 1 kilo ohm resistor in out put lines..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:48:17 PM
now time to check out...set metr in to respective mode and measure the voltage...
now load test..an  RS 380 motor with a three blade prop..at load...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:52:39 PM
make sure there is no over heating, and seal the board with silicon..
now application to the radio RX...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 07:58:31 PM
can operate any radio..and with any servos...
but i request to you all to use a T I P 3055 instead of MJE 3055, as it is far capable than smaller one..lasts for a life time...
you can add a diode, in the input line as a protector of reverse polarity, and can add a zener dioe with a 520Ohms resistor, in the input of the power transistor, to fail safe..

will take a good load for hours..and for years...please add a fuse in output lines and its capacity is up to your needs.

see the cool working of this device...

will continue...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 08:03:56 PM
http://www.youtube.com/watch?v=imZOCB27-ro


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on December 29, 2011, 08:11:27 PM
how to connect it..follows..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: Dharmik on December 29, 2011, 09:29:37 PM
hi roopesh you always came with useful stuff. Can you complete one request from me. If possible please post tutorial about simple DIY navigation light(blinking leds) circuit?


Title: Re: make our own B E C, E S C s for our crafts...
Post by: KALYANPRODHAN on December 29, 2011, 11:17:59 PM
BECs should be designed with more volts insted of lower voltage and so if designed, it should be with 6 volt. Just insert 2 nos 1N4007 diode between 7805 middle pin and negative rail and voila, a 1.2 volt boost you will get. So, voltage = 5+(2x.6) - 0.7 = 5.5 insted of 5-.7 = 4.3 volt.

But another Issue. LM78xx series requires a dropout of 2.2 volt for faithful regulation. So, you need 3S for this and 2S will not be suitable. So, use LM2940CT-5 rather than LM7805. It will cost you Rs 28/- over Rs.5/-

As the flight weight is critical, so we cannot use it for aeromodeling due to 2 reason.
1) Weight of HeatSink and
2) Power Loss and flight time will be lower.

However, you can use this in Car, Hovercraft, Ship etc.
Better use Switched Mode regulator.

An simple circuit is Black-Regulator or RomanBlack. Just increase Inductor current capacity and main switching transistor with higher current capaciity (Preferably with MOS) and Capacitors with Tantalum Capacitors and you get professional grade BEC. For inductors, you prefer small ring core for more inductance.

A link is here.
http://www.romanblack.com/smps/smps.htm

Just Replace free wheeling diode D1 with 1N5822, BC327 with D882, R2 with 0.5 watt resistance. You will get 3A switched mode BEC.
Also previous topics :
http://www.rcindia.org/wanted/wanted-an-external-bec-for-2s-lipo/
and
http://www.rcindia.org/batteries-and-chargers/battery-for-fuel-powered-plane/


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 03:33:27 PM
Hai..Kalyan..i was expecting a posting from you, with some internet links ...as usual..i am too thankful to you, that your opinion came to me as an eye opener..and gave me a golden chance, to take a deep research in same subject, not alone, but with my R&D team, and working on some stuffs related to same matter, and found some astonishing facts about the B E C, and E S C. and i am too happy and proud about my arrangements, and my own stuffs related to my modeling...i will share all of research results and findings here, so we can understand related stuffs more..i red your posting about the same day, but was carrying on my research with team..still working..exploring more goodies and some more about new devices...and from your comments it is sure, to understand that my simplest set up is far superior to a commercially available same one..thank you again..i do not have any internet web site links to post here, as none of them aren't my works, and to me, we must research, work and find ouselves..for that we need only the basic diagrams of a device, from its manufacturer and not a circuit..with the shematic we can design our own needs..this not an argument..dispute or not boasting..but, i am thanking you, that i started my team research in this subject from your above posting..will share all of my findings...Happy New Year...to you all of my Friends..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: KMohanan on January 01, 2012, 07:02:06 PM
Roopesh, I highly appreciate your attitude. Thinking our own and finding out things, refining/correcting them, getting support from friends with similar thinking... All are very satisfying. Think of improving Quality and Reliability in the designs. Also, making designs with specific applications in mind will be very useful to the community. This will enable you to get you total professional satisfaction and at the same time contributing to our country's indigenous development efforts. If we have a determined mind, nothing can beat us... Wish you and all your efforts all the best in the new year 2012.


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:28:13 PM
Mohan..its happy to see one more dedicated modeler here...its a nice thing that in this new year occassion..none of my efforts are for money making but i know sharing our knowledge will be too useful to all others..once i was wandering to aquire knowledge in model making..and i know the value of aquiring some knowledge in modelmaking..it makes our models even more worthier..all with less cost...

friends..i am sharing all of my proven ideas and arrangements here, for good thing, all to us, is all i learned from my own research and hard work.its all not a boasting, one man show, or false proud..instead i started sharing my ideas here, because i am getting lots of personal requests in my mailbox, and yes through mobile.all of my shared works are true, and proven, not in theory, but in real crafts in various segment. i am happy that after posting this article in our Forum, 6 modellers able to wire this B E C circuit, and happy to here it is working nicely.


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:34:01 PM
Kalyan, here answers for your querry...
its not nessesary to wire a B E C with a high voltage, than required, if it is capable of handling high currents, up to some extents. my research shows us that (Photo) most Receivers are based on 4.5 volts to 6 volts, and if you are working with less current its not an issue.  If you want to get a 6 volts from the same set up, it is not nessesary to add any diodes in between the pin no 2  and Gnd, but can use a 6 volts regulator, 7806, or can simply attach an L E D, between the pin 2 and Gnd. so can attain 6 volts in out with T I P 3055.and if we want to get even more stabilized supply to RX, can use a Darlington pair with T I P 3055.

i found nothing bad with dropout voltage up to 4 standard servos, with 7805 alone, in 6 volt input, except some heating.and its not a matter  related to 2S or 3S,but with the input voltage.it must be 6 volt at least, with any battery. it is not nessesary to use LiPoly battry packs, if we are working with a water or land based models..we are liable to use the LiPoly batteries on rc planes because of the weight issue..and i found some of my water based craft behaves even more pwerful with S L A battery as it is designed for 13.2 volts instead of 11.1.
 the photograph shows the input voltage is 6.5 volts is far enough for to get 4.9 out..

and in my detailed study, i came to know that the 78XX series regulators are well protected against short circuit, over heating and many many more.if you are interested, in 78XX regulators you can look in to it's data sheets. i connected my radio set with 4 servos, and later 6  then later 4 heavyduty with 2 high toprque servos, only with 7805 alone, with a tiny heat sink, at first with 6 and later with 12 volts  input.the only problem was a little over heating, because of the tiny heat sink.


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:36:59 PM
here the fly sky receiver showing that it works from 4.5 to 6.5...
and showing the input voltage..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:39:32 PM
and if you found any trouble with 78XX regulators, please stop using most of the commercial E S C s as all it's B E C s are powered with two 7805 regulators in parellel..below photograph shows my tests, as i delibrately overloaded the B E C line, with an electronic circuit,later stoped workig and i lost the unit..its a brand new 20 amps ESC..and second photograph showing the blon out mosfets as i delibrately over loaded it with a heavy motor, as the manufactures written on it as 30 amp ESC..and it blon off with a load of 14 amps, continious..these study shows me that none of any electronic devices are capable up the limit that written on it...its too easy to use these own made electronics in an rc plane model, as most of it weighs less than commercialy available ones..here you can see a commercialy vilable E S C, noted as 30 Amps, and with a BEC of 5 volts 2 Amps. i opened it and checked its B E C circuits, is same with the 7805 configuration..and it is made from an industrial plant with sophisticated facilty..and SMD..still it weighs 30 grams..
second photograph shows the same BEC wired by me, is capable of 8 amps continues, is weighs only 25 grams..all with rough made, on a vero board, with a heat sink that i can buy from the market..all hand made with big capacitors available..no SMD componets..and the third photograph shows the ESC with same B E C circuit, is capable of driving a CRSE 1200 motor, with ease..and it weighs only 70 grams, because of its heavy heatsink, is a delibrate attachment...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:41:59 PM
see here..commercialy available E S C..still using two 7805 regulators..in parrellel..and you can check it out with meter, in continuity mode for contacts..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:44:42 PM
and i am too happy to know that these of my simpleset circuits are powering some of my extra ordinary crafts and project works without any trouble..still going on...the same B E C circuit is powering my latest U A V with a wing span of 70 inch, with full capability, all with 6 heavy duty servos, and camera.she is powered by a 60 engine..the second one is "RED EYE" is a U A V with almost same wingspan, with a immensly powerful ECM.she works on 14.8 volts..and the third one is based on Thundertiger cessna, 177..with camera and G P S..
so happy..

its a burnt ESC as i tried to load within its limit..

and the simple B E C driving along with G P S co ordinator for car models...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 07:51:21 PM
and you can see the given circuit about the roman black..i know only a few among us are capable of reading and tracing the complicated electronics circuit, so it is feasible to go for a simple but effective circuit..if i post a B E C circuit with a MCP, how much of us are capable of making one..? still i will share one proven circuit here, but my experience taught me that i was wasting my time, money and manhour to make this ultra complicated B E Cs, but worked same as the above mentioned circuit..and this same circuit can be used for battery charger, is capable of charging 1.2 volt any ampere battery..to 12 volts 9 amps battery..with a same configuration..with a little modifications...

to under stand the limitations and capabilities of 78XX series regulators, i took a gruesome research work on 78XX regulators..from the data sheet, of KIA 7805, got by my request, i found many positive thinks and limitations about these device..so to understand it more i started the nerve racking of the 78XX...i know this device from my earlier electronics life, as i joined as a service technician, in Sony Corp, especially in some heavy series of audio and video systems, as the voltage regulator for the P L L syth: and MCPs.the only addition was the heavy heat sink..
so i started...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:05:41 PM
i added nothing but a 1000 uf capacitor and a heat sink...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:06:52 PM
and can see its working nicely with a simple 6 volts battery..with 4 standard servos and 4 HD servos..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:08:29 PM
the sum result is satisfying but the device was heating up...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:11:37 PM
and with 12 volts..
i told you..the device was heating up as it alone drives the HD servos..so, all we know it is not feasible to leave a power device to its limit..still nothing wrong is happened because the device is protected from over heating..
so i added an even more versatile configuration..as a Darlington pair...with T I P 3055..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:16:24 PM
we do not need to add any diodes in between pin 2 and ground, but can add an L E D, between these two leads, also acts as a power indicator..so you can see the output voltage stepped up to 6 volts..
but i request to you all, that if you are working with cheaper quality servos, it is advicible to go with 4.5 volts..because i have many bad experiences with cheap servos, as i tried to add some loads with 5 volts..and make sure your servos are good in H bridge circuits..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:19:38 PM
and with DP config this unit became more versatile..no input loss..(negligible), no over heating..and driving HDs a lots..still working on real crafts..test continues..


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:23:19 PM
Friends..will share some B E C circuits that employs some complex components..research a lots yourselves..in your model making..and we will sucseed at will..imagine our craft completed with own ideas...its unimaginably satisfying...inspiration never ends..it will continue..on..and on...and on...


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:25:26 PM
see some experiments here..with BEC..
http://www.youtube.com/watch?v=NfANvvHoF7c


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 08:31:22 PM
once again..research yourself a lots..make your crafts even better..yes..not with complicated ideas..but through simple ideas...we must leave the ignorance behind us..and must study ourselves..wish you all a happy prosperous new year..with loads of nice crafts... (:|~ (:|~ (:|~ :thumbsup:


Title: Re: make our own B E C, E S C s for our crafts...
Post by: KALYANPRODHAN on January 01, 2012, 10:59:46 PM
KIA 78D05 is the low drop out 5 volt regulator unlike LM7805 or simply 7805 But similar to LM2940CT-5
Datasheet is here (http://pdf1.alldatasheet.com/datasheet-pdf/view/69423/KEC/KIA78D05F/+4J4_WUhwC/1KIDzwpBwM+/datasheet.pdf).

Consult A. P. Malvino's 3rd Edition of "Electronic Principals" for any type of design. The simplest design book I have ever seen with Rock Solid Backbone and fine tuning.

LED is equivalent with a series Zener with resistance. So loading or input voltage variation varies the current of LED and the voltage across LED changes as the equivalent resistance drop changes. So, it is always preferred either a voltage divider with output to ground and connect the center pin of fixed Zener voltage or Diode string (Similar to diode).

If you add 2 transistor in Darling Pair as buffer, then 1.4 volt drop at output occurs.
Red LED is equivalent to 1.6 volt zener with series resistance. To avoid voltage variation due to change of current in LED use 2 nos of 4007 or 4148.

But the simplest is using one zener, resistance and Pass Transistor. Insted of using vero board, use metal TAB heat sink.

The best one is switched mode BEC for higher battery voltage.

And the cheapest ESC for 2S is make 3S3P diode array (1N4007) and make series with positive voltage drop. You will get 7.4 - (3x.7) = 5.3 volt (theoritically)

but practically you get 6 volt. (guess why?) ----------- Home Task.
Consult any book except I recomend.

Try it.


Title: Re: make our own B E C, E S C s for our crafts...
Post by: roopeshkrishna on January 01, 2012, 11:08:37 PM
Thank you Kalyan..and continuing my research, to make my BEC even better..and found we do not need any complicated circuits then as this circuit powered a big craft with two motors and 4 HD servos..and some switched BEC is making some interferrence especialy in an FPV and UAVs..still happy..DP configuration makes some drops in voltage, but gives a better stability..and if we want to alter the output voltage according to our needs we can add a even simpler device in between..no need of further book referings..but must find myself by research..once again..thank you Kalyan..inspiration continues.. :thumbsup: