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RotorStar 120A HV (4~14S) Brushless Speed Controller (OPTO)

RotorStar 120A HV (4~14S) Brushl...

We are proud to offer our Hobbyking RotorStar ESC series. With helicopter specific programming options such as super smooth soft start, fixed RPM mode (governor mode) and ultra high resolution, you won't find a better helicopter ESC on the market ...

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We are proud to offer our Hobbyking RotorStar ESC series. With helicopter specific programming options such as super smooth soft start, fixed RPM mode (governor mode) and ultra high resolution, you won't find a better helicopter ESC on the market today!

We have tested these units on our own helicopters and found them to be among the best we have ever seen. The super smooth soft start, along with its ultra high resolution throttle response puts this ESC in a class of its own!

RotorStar ESCs are built with the highest quality components to ensure true-to-rating current handling and high efficiency operation.

All RotorStar ESCs can be programmed via optional programing card or by transmitter stick inputs.

• HV capability for use with up to 14S (51.8V) Lipoly
• Optional programming card for convenient setup 
• ESC had separate programming lead built-in so there is no need to unplug from RX
• Super fine throttle resolution provides first-rate and highly accurate linearity 
• Super smooth adjustable start-up mode
• Constant RPM mode (governor mode)
• Adjustable F3A brake.  
• 3 steps adjustable normal EMF brake  
• High anti-interference capability
• Low voltage cut-off protection with automatic adjustment for NiCd/NiMH/Li-Ion/LiPo/LiFePO4  
• Soft cut-off option at low voltage, slows motor RPM gradual rather than hard cutoff (LVC)
• Low voltage cut-off can be disabled  
• Variable cut-off voltage / cell    
• Active free-wheeling circuit allows for unlimited "partial load" capability
• LED status display  
• Adjustable motor timing from 0° to 30°  
• Blocked rotation protection (senses a jammed motor and stops motor rotation)  
• Motor reversing from ESC (no need to change ESC/motor wires) 
• Over-temperature protection and overload alarm  
• Anti sparking circuit: reduces connection sparks 
• Throttle signal lose protection. If the signal is lost for 3 seconds, the power will automatically cut-off.  
• Safe power-on. (Motor will not start until throttle is returned to lowest position)

***This ESC is compatible with both helicopter and airplane models.***

Max Cont Current: 120A
Max Burst Current: 140A for 10 seconds
Input Voltage: 4-14 cells li-XX or 12-42 Ni-MH/Ni-Cd battery
BEC: None (OPTO)
PWM: 8~16 KHz
Max RPM: 240,000rpm for 2 Poles Brushless Motor
PCB Size: 68x53mm
Weight: 164g (including wires)


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Great ESC. Used in TT X50e. Programming card a must and for £5. A little bulky compared to other amkes making mounting a litle more difficult. Seperate progeamming lead a good idea. Running 6S and 1100kV>YEP 20A SBEC>UltraGuard.
I have had many cheap Hobbyking items and I've never had a problem. This has been the first problematic electronic thing I've had from Hobbyking in the thousands of pounds I have spent here. This ESC was pretty cheap for what it does so I went for it (bear in mind that a YGE is completely and utterly overpriced, even if they used military grade components then you could not make it cost that much). It worked 100pcnt perfectly for the first two flights in my helicopter (a Hirobo Cobra). Then on the second flight the motor started cogging on spool up... So I put it on the bench and made a voltage booster for the throttle signal. This made it work better but it had lost all of the settings. Re-programming it made no difference. I kept trying and eventually it totally died, it won't even power up now. I took it apart to have a look (I am an electronics engineer by trade) and nothing seemed amiss however the main MCU (ATMEGA168) had totally died. It's very unusual for an Atmel chip to die like this so clearly they are using QC rejected items. Very unimpressed. Now that I've opened it I cannot get my money back either...
Bulletproof ESC, will put this in my Dechatlon 2450mm, with 6374-200Kv motor. Same as YEP 120A HV, but cheaper :)
Este regulador cuando funciona se programa con la tarjetaHobbyKing YEP ESC Programming Card II
El mio le programe pero dejo de funcionar y ahora trato que H.K. me de uno que funcione (gratis claro)
Puede alguien decirme con que tarjeta programadora vale para este regulador , con el stick de la radio es un coazo
Upgraded my trex 600 to a 750mx motor so needed an upgraded esc, so purchased this. 3 flights today and very thing running great. I would recommend as it is alot cheaper than the castle equivalent.
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