MMM V2 Bec 6V possible?

[ptt81]

my guess is that the fan will no longer work?

[Arct1k]

No... technically this doesn't disable the bec it just stops the BEC powering the RX and the servos.

The BEC would still power the fan and the brian board - although easy to to remove the fan plug from the bottom of the MMM and rewire to run off of the RX / UBEC.

The MMM does not have an opto mode which would mean the ESC brian board is powered from the RX and the red wire is left in.

[BrianG]

Originally Posted by Arct1k

...The BEC would still power the fan and the brian board - although easy to to remove the fan plug from the bottom of the MMM and rewire to run off of the RX / UBEC.

The MMM does not have an opto mode which would mean the ESC brian board is powered from the RX and the red wire is left in.

I just took my MMM apart and I could not find a brian board anywhere.

[TruckBasher]

Brian, do you think the MMM BEC unit can handle the Robot Servo (6V-7.4)?

[BrianG]

Considering the torque and speed of a servo is lower at lower voltages, I would technically say yes. Patrick can provide more info, but I would feel a bit leary of hooking up a high current load on the internal BEC. BECs are efficient, yes, but they still get warm with higher currents.

[TruckBasher]

My servo is Hitec HSR 5995

Torque: 333.29oz.in @6V
Speed: .15 seconds/60° @ 6V and .12 seconds/60°(@7.4V) max
Current consumption: 300mA(@6V with no load) 4.2A(@6V lock)
380mA(@7.4V with no load) 5.2A(@7.4V lock)

It has been working on the KoolFlight BEC for a year with no problem but not sure which of the MMM BEC (5.5V) or the CCBEC can be the better option///

[BrianG]

Well, the CCBEC is rated up to ~7A. However, if it decides to fail, it might take the servo and receiver with it. I have no idea if the MMM bec is based on a similar design and what happens when it fails. If it's been working on the KF BEC, why not keep using it?

BTW: The max current draw @ lock is basically saying a stalled motor. As long as the wheels are fairly free to turn and the servo throw isn't fighting against any mechanical stops or steering limits, the real current should be less, and the average current far less.

[TruckBasher]

got...i guess I'm off to buying another KF BEC..I gave my other one to the guy who bought my MM...

I hope Patrick can reply if the MMM is biased..

Thanks Brian...