HobbyKing Micro UBEC 3A / 5v

 fireball412 433 points

It depends. This BEC is very small. It is similar, may be even less powerful, than most integrated BECs. This device is more suited for application where space and weight is critical.

 fireball412 433 points

There are dedicated APM power modules available. One has 5.3V and supplies up to 2.25A. These are quite similar specs compared with this device. You should double check all your components regarding power consumption. The specified current of all components should not add up to more than 3A/2=1.5A. If it is more, I would use a stronger BEC.

 fireball412 433 points

Sure, why not? 4S is between 2 and 5S and 5V works for every receiver.

 VetyCZE 4 points

Yes, it may function. Why not?

 fireball412 433 points

Have a look on the backside of the kk2 circuit board. you will see that the middle and lower pin of alle channels are connected with each other. The same is true with the receiver. when you connect any channel with the rx you connect ground and 5v of both devices. It does not matter where to provide the power into the system. Both ways will work.

 Antonio 5 points

Can this be used for an ignition system?

 fireball412 433 points

Please start a separate thread (new topic) and please specify what kind of ignition do you want to use.

 Tanmay 8 points

Which flight controller are u using

 Arxangel 971 points

The BEC should go to your flight controller. When you connect the flight controller to the Rx, through the channel wires, the flight controller will supply power to the Rx.

 fireball412 433 points

An ESC with opto is powered by the flight battery, like all other ESC. It does not power the receiver that is why you need this BEC. it is connected to the receiver.

 Arxangel 971 points

Not necessarily. He said "Flight controller", and I assume he means the KK2.0 multi-rotor flight controller. If he is using that, either with normal ESCs, or with OPTO ESCs, the flight controller always supplies the power to the Rx through the channel wires. In this situation the Rx does not get power directly from the ESCs or the BEC, but from the flight controller. He will have to connect the separate BEC to a pin on the flight controller that he is not using for ESCs.

 fireball412 433 points

it does not matter if the controller powers the rx or if the rx powers the controller. All ground and all 5v pins are connected with each other. I would always provide the power to the most critical device. However, in this case both components are equally critical and we have no servos that draw current. finally i would say that it does not matter where to connect the Bec.

 Robwuk 1 points

All sorted now, thanks, connected to rx spare channel, KK2 lit up and has been working fine. My problem now is waiting for a new arm, had crash :(

 fireball412 433 points

When your ESC does not have an internal BEC (opto type) you do not have to worry. Just plug it in as you described. The connection between BEC and battery can be done exactly the way you describe it. You can either use the outer wires of the balance plug or the main leads of the battery. I did both in the past. I prefer using the main leads since I do not completely trust in the reliability of the balancing connectors. Finally, you do not need a separate battery for the servos. Some people still use an extra battery for mainly two reasons: 1. being independent on the discharge of the flight battery or 2. the flight battery has too high voltage for the BEC they want to use.

 hate2crash 13 points

I have several planes that use same batt packs...all currently use esc's with built in ubec's... i understand the balance plugs could be a less dependable connection verses main battery leads... But how can you wire into main leads without splicing wires or adding leads to female battery plugs? again not sure i would want to have extra wires soldered on my packs...but if there is a simpler reliable way i may do it..thax

 fireball412 433 points

When I solder the connectors to the ESC, I integrate a small extra wire (behind the connector). This wire is routed to the BEC. This is much more convenient than using two sets of connectors.

 hate2crash 13 points

yes that seems the best way ...actually just soldering this units wires on male connector same time you solder connector to esc is ideal and these ubecs are so small anyway...thax

 fireball412 433 points

Ok, now it makes sense. Using the external BEC, you must disconnect the red wire of the ESC. The black wire of the external BEC must be connected to the black wire of the ESC. The red wire of the external BEC must be connected to the pins that were previously supplied by the red wire of the ESC. It does not matter how you obtain this situation (soldering, y-lead). The white wire of the ESC must be connected to the receiver and the LED-system.

 fireball412 433 points

Removing the red wire of the ESC must be done if your ESC has an integrated BEC. However, then I do not see the reason why using the external BEC is this application. Please explain why you are using the external BEC. Please also name all components that are used: receiver, ESC, servo, car size

 fireball412 433 points

I read 5 times through your post, but I cannot make any sense out of it. I downloaded the manual of the 3racing LED system. I assume you are using it in an electric car. All car ESCs I know have an integrated BEC. In this case you do not need an external BEC at all. You need a Y-cable.

 fireball412 433 points

This device has two sets of cable. One side goes into the receiver. The other two wire are connected to the battery. The white wire of the ESC is the only wire (of all possible wires) that is not related to any of these things.

 fireball412 433 points

An external BEC serves the same purpose as an integrated BEC. It reduces the voltage of the drive battery to 5-6V to power the receiver. Some people do not trust in internal BECs powered by high voltage batteries. The difference between the voltage of the drive battery and 5V stresses the electronics of the BEC. That is why people sometimes use an additional 2S battery together with a BEC (voltage regulator) for the receiver. I would not do this for a boat. I would either use the integrated BEC of the ESC or if this has been proven to be unreliable I would use an external strong (5-10A) high voltage (6S or higher) BEC. Nevertheless, this device here is extra small for ultra light flyers. A boat is large and weight does not matter.

 fireball412 433 points

What is a fe boat? Do you mean a boat powered by LiFePO4? How many cells do you use? What kind of servo? What kind of boat?

 QuadSB 441 points

Hi Jacobus, it will work fine with any DC voltage you have available. As long as it is within the specs, (6-23 volts), it doesn't matter whether it is from a LiPo, lead acid (SLA, Car batt, etc), a laptop PSU, AC adaptor etc, etc, it doesn't make any real difference! Hope this helps.

 fireball412 433 points

I use it in a DLG. It provides enough current for four small servos. It is small (PCB: 20mm x 20mm x10mm) and light weight. I recommend to remove the heat shrink. Mine had a metal covered foil beneath. I destroyed one of them by mechanical pressure. The metal foil short circuited some wires. I used normal heat shrink instead. Shielding is not an issue today.

 Manmohan 26 points

is it good for the hobbyking micro composite dlg glider

 fireball412 433 points

Why not? it is small, light and provides sufficient current for small servos.

 Manmohan 26 points

what kind of dlg glider do you have

 fireball412 433 points

I have an Ultrawing DLG by modellflug-technik. I am currently building a RCN09. There I also use this BEC. - Why are you so currious about the suitability of this device? It has good evaluations, it is cheap and it matches the specs of a DLG. Just give it a try.

 fireball412 433 points

A device can not have a 5V input with 1000mAh. It is the wrong unit. The current in measured in mA. The unit mAh specifies a charge or capacitance of a storage or the integral consumption during a time span. I believe the device requires 5V and 1000mA. This BEC delivers up to 3A and works up to 5S. Thus, using a 3S is ok. Your battery will last around 10h. I believe this is enough. Be careful it will not shut down when the battery is empty. You must observe the state of charge.

 David 1 points

You are correct in mA. I use an alarm on my batteries to warn me ~10.5 volts, so running flat will not be an issue. Thankyou for your response.

 fireball412 433 points

The integrated BECs of many ESCs are usually not very strong. Large digital servos require a lot of current. Using an external BEC allows you to choose an appropriate device for each purpose. In addition to that you still have control of the model in case of a failing ESC. However, the Micro UBEC of this page has similar performance than most integrated BECs. The HXT UBEC is much better.

 Marc Volovic 66 points

Yes, it is within tolerances

 glenn_mech 338 points

absolutely

 sklenar 127 points

It depends on which servos, so it is not possible to give really true answer. But it works wery well, even at permanent load 2.6A it stays cold. So, for normal servos (not extremely fast), I may GUESS that yes, You can. Throw a towel on the plane (to load servos somehow common to airflow), and keep moving all sticks for few minutes. This is the easiest test that should unveil the problem if exists.

 weekendflyer 966 points

****

 Heppy Ket 401 points

No you need to solder a connector on yourself, the advantage is that you can use what you like.

 victorhuge 34 points

I don't think so, that only works with batteries, maybe someone knows better

 jimgreen360 18 points

NO! It will fry the ubec's as they are switching UBEC's

 The General - x5 141 points

Yes it will work, the outputs are dampened by capacitors you will get an equivalent voltage, this is pulse width modulation where you get 40 on/ 60 off and take the average of that. The high switching will get you an average voltage say 5 volts, but under the oscilloscope you can see it's jumping between 0 and 11.1volts. The output voltage ofcourse then buffered and put under an inductor to keep the voltage stable. So yes you will be able to ad it in series.

 sklenar 127 points

common ground should cause short circuit of lower BEC, once ground of upper bec is connected to its positive terminal.. You would need galvanicaly separated devices to even think about series connection.. There is 12V BEC offered here, is it too much? Perhaps try to modify that.

 raskal 237 points

the ferrite is suppose to help reduce elecromagnetic parasite(voltage noise) to and from other device.

 The General - x5 141 points

Reduces noise. Without it the high frequency switching may generate enough noise overtime to charge up into a full blown EMP bomb. Your fun fly buddies are going to hate you for causing a blackout in their radio equipment when they find out that you have removed this ferrite ring. o.O

 sklenar 127 points

At 2.4GHz there should be no need to use ferite rings at all. They works like a charm blocking high frequency noise passing parallel by both wires together, but they do not have any effect on voltage or current (including noise) between those two wires.

 ccatalin 240 points

strange words...

 chopchop 144 points

i like turtles

 HAKAN 10 points

out voltaj 4,9 V

 andy65 112 points

Ubec Specifications: Input: 6V-23V Output: 5V/3A Life voltage level:3.3V/cell max.charge voltage:3.6V/cell if you have 2s it mean 7.2V max and 6.6V min. This ubec work fine with your 2s life.

 Ronald007 406 points

Yes it will. A UBEC is used to regulate the power supplied to the radio gear and servos. You will use one if your ESC does not have one built in, if the built in one does not supply enough amps to adequately power the servos, or if you don't use an ESC at all. When in use, it will maintain a preset voltage and amperage supply for your electronics. So it will take the 2s 7.2v and reduce it to a constant 5v at 3amps.

 Mitja 5 points

Sure :)

 chopchop 144 points

anything more than 6v in is good

 juanfe 6 points

La Proteccion ante conexion inversa no funciona. Se quemo! en 12 volts. Esta mal lo que dice HK. Cuidado!
The inverse protection polarity dosen´t work. It´s burned on 12V. Wrong when HK says "polarity protection", be careful. Waiting almost 2 month and Puf!

 HAKAN 10 points

i work with 2s life 700 mah. no problem. good work

 BossJay 159 points

Yes you can use this with your 6S Lipo. BUT, you will have no more allowance on your UBEC. Your UBEC might be destroyed by the Voltage surge when you connect the fully charge lipo batt. That is why the Max recommended Lipo is up to 5S only to give your UBEC a 3.7V allowance to be on the safeside.

 andy65 112 points

No you cant because, full charge 6s lipo voltage is 4.2*6=25.2V, This is out the range

 CharlitoCZ 22 points

Its becouse a loaded lipo has 4,2V, not only 3,7.

 saipoon 6 points

Tx guys! Now I understand. I will connect the bec to a seperate 2 S lipo.

 CharlitoCZ 22 points

thats the best way :-)

 Awni 165 points

my guess it is functioning as a heat sink to keep the PCB cold

 andy65 112 points

The shield is to protect RX against radio frequency interference from the UBEC.

 Ronald007 406 points

I agree with andy, sounds like a shield to porotect from signal interference. Still, it's a good practice to keep ESC's, motors, and UBEC's as far away from the radio gear as possible.

 Javet 14 points

Hi Awni, some testimony here said 3 layers cover (shrink tube, alu sheet, thin plastic sheet) prevent the air to get in and out, thus this UBEC easily gets hot.

 Mnekap 13 points

UBEC gets hot because it is burning off excess voltage and converting it to heat. The Metal foil is not as a heatsink primarily, but more for signal interference shielding as Andy65 correctly pointed out

 Javet 14 points

Ok, thanks Mnekap.

 Ronald007 406 points

Agreed. That's how electronics deal with reductions in voltage and resistance, etc. The byproduct is heat. So when you charge a battery, balance a battery, use ESC's they will release the excess energy through heat. Putting a heat sync on motors, placing ESC's in the airstream, will extend the life of the component. Wen they heat up, it reduces their lifespan.

 Daniel 5 points

It is a protection shield, because this is a switching mode (PWM) UBEC. It means it works as a DC-DC converter. Usually switching frequencies are below 100KHz.

 MikeyFlys 67 points

Removing answered question.

 mr.sneezy 264 points

Well the 'protection' shield sort of did the opposite for me. Two sharp component pins pierced the foil on the underside, the 5V output shorted to 12.6V input. Trashed a very nice servo, but not the FrSky receiver thankfully. No more shield on mine, I'll risk is as the lesser of two evils.

 Ronald007 406 points

The turnigy will handle a slightly lower input voltage at 5.5 volts compared to the HK's 6v minimum. The turnigy also has an adjustable output of either 5 or 6 volts. Both have a 3amp output. So depending on the needs of your receiver, the turnigy will allow for more volts. The turnigy is only slightly heavier at 7.5g compared to HK's 7.3g.

 christiano 78 points

this is smaller than turnigy

 ..j.. 30 points

I use hobby king ubec in my car it is easy to hide verry small dont have any problems with it.

 Awni 165 points

I agree totally with Ronald007, very well explained

 MikeyFlys 67 points

Removing answered question.

 Javet 14 points

Yes, Mike. And if the ESC already has BEC integrated in it, don't forget to remove/unplug the middle wire of ESC that connected to RX or you'll fry your RX. Have a good flight =)

 christiano 78 points

yes you can do it. but if you want you can use other battery just to the esc.

 Michael 1 points

Yes, you can connect this UBEC to your main battery

 Awni 165 points

Yes you just plug it to the battery balance port

 Phil S 37 points

To avoid extra connections with subsequent risk of accidental disconnection, I soldered the UBEC in. Input wires are soldered to the battery input tabs on the ESC circuit board and the output leads tapped into the lead between ESC and the RX.

 Ronald007 406 points

Yes, solder it in to the plane side of the battery connector with the esc leads. Then make sure you DISCONNECT the red wire from the lead that plugs into the receiver. From the ESC. If not you will fry your receiver.

 MikeyFlys 67 points

Removing answered question.

 BossJay 159 points

To be on the safe side. To avoid any malfunction on the servos, It is better to use the Hobbyking HKU5 5V/5A UBEC. Because you are using more than four servos.5V-6V is what the receiver needs to function properlly. I think you are using 9 servos in your airplane. To avoid crashing your expensive P40, Better order the Hobbyking HKU5 5V/5A UBEC or any UBEC with 5V/5A Rating. Anyway it is only $5 than your $$$P40.

 Javet 14 points

Hi there Customer, in my humble opinion, if we think of UBEC as a gate, its task will be to pass the current not more than 3A with voltage of 5V. Now from your description (please correct me if I'm wrong), I assumed there will be 2 servos for flaps, 2 for retracts, 2 for ails, 1 for rud, 1 for elev. There are 8 servos in total. Let's say you use HXT 9g servos. Some say it draws 250mA each. IF in some point, those servos are all operated in the same time, the total current drawn will be = 8 x 2

 Stephan 5 points

Looks like I need to ***p up the BEC. So Javet, I need a 5v 16 amp BEC? (8x2)? Still unclear. I know what it does, still don't understand what I need.

 Javet 14 points

My prev msg has been truncated by Hobbyking. = 8 x 250 mA = 2A. That's just for the servos. The RC receiver will also draw current from UBEC. Futaba receivers draw 8-10A (futaba-rc**** faq). AV TX as well. So find out amp of all devices you are using, but only the ones which need 5V supply. Sum up all the amps. Use that result to decide UBEC amp.

 Daniel 5 points

It means at output you can get 3 Ampers of current and 5 Volts of tension. Usually receivers and servos are working with 4.8-6V. Output current is enough also for 4-5 standard servos. So, because you have at least 5 servos, it's better to get a bigger one: Product ID: 5AUBEC Specifications: Input: 6V-23V (2-5S Li-Po) Output: 5V/5A