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[funtimefrankie]

The instructions for my Graupner Schottel drives advise that a separate 1.4 amp/hr power supply for the hi-torque servos.
Anyne tell how this is done, I thought that the (extra) servo  battery would supply the red and black to the servos whilst the red back to the rec. is disconected. Does this sound right.

Or is this nessessary, as the Mtronik ECS has a 1.5 amps. BEC?

[malcolmfrary]

If I've followed the description right, yes, this should work OK.  Even a 1.5A BEC might struggle and cause a volt drop just when its not wanted.
Anybody out there using Hi-torque servos can give a practical, rather than theoretical answer?

[Bluebird v2]

hi there

Am I reading this correctly? you are planning on disconnecting the red and black power supply that would normally go to your RX? from your Hi-Torque servo and connecting these up to an independent battery supply?

Just leaving the signal wire going to your RX.  If this is the case, sorry I doubt it would work.  Your Mtroniks BEC with 1.5 amp supply has got enough umph in it to supply your servos via your main battery.

The other alternative would be to use a larger amp supply battery for your RX, but, maintaining the 4.8 to 6 volts range.

Hope this is as clear as mud.

Aye
John E
Bluebird

[FullLeatherJacket]

1.4 Ah isn't very much these days, is it? You can buy a 2.4Ah 4.8v pack for less than the price of a fish supper, and avoid all the wiring hassle of a separate battery.

I suspect there's a Graupner item recommended in the instructions to fit the bill here.......at twice the cost of the same thing from somewhere else.

Cynical? Moi??  ::)

FLJ

[wombat]

I suppose I shouldn't suggest this, but if you want to run a separate battery for the Hi-torque servos - what I would do is get a "Y" lead. Disconnect the red lead at the reciever socket - this prevents the battery powering the reciever. Connect the battery to one socket and the servo to the other. Of course you will need a separate power supply to the reciever - say the BEC for the M-tronics unit.

If you are runnig a couple of these scottels, it may be a good idea to have a separate battery for each one - dependin on how much elastic-trickery they consume and how much the trackwork in the reciever can carry. A few more specs would help though.


Wom

[funtimefrankie]

It was only the red I was planning to disconnect, like when you have two ESCs.
Thinking about it today I may put the two steering servos together, on a Y lead.
I think it comes down to the 1.5 amps from the ESC  versus the separate battery, as FLJ says 2400 is not uncommon these days for AA cells.

[Telstar]

Hi I am not sure what type of Hi-torque servo that is being used.  I have 2 elderly Futaba hi torque servos that have separate battery connections ( that is the normal 3 wire from the RX AND a separate 2 wire battery connector ) These servos will not work without both supplies.

Am I reading this correctly? you are planning on disconnecting the red and black power supply that would normally go to your RX? from your Hi-Torque servo and connecting these up to an independent battery supply?

'
This will never work. the signal relies on the negative supply (black wire) for its 'earth' return

A 1.4AHr lead acid (gelcell) battery is capable of supplying a lot more current (amps) than 1.4 amp even if only for a short time (double the current - halve the time)  but a 1.5Amp bec will be damaged if you try to take more than 1.5amp from it (unless it has current limit protection in which case it will greatly reduce the voltage to the RX and servos)

I share wombat's concern

it may be a good idea to have a separate battery for each one - depending on how much elastic-trickery they consume and how much the trackwork in the receiver can carry. A few more specs would help though.

as to how much current can be drawn through the RX when using Y leads etc before the PCB track in the RX melts


I hope to include a sketch of a possible solution

cheers Tom

[funtimefrankie]

Thanks for the help.
I think the diagram above is what I tried to decribe in my first post.
I'll try that when I have obtained the bits I need.
Frank

[glennb2006]

I suppose I shouldn't suggest this, but if you want to run a separate battery for the Hi-torque servos - what I would do is get a "Y" lead. Disconnect the red lead at the reciever socket - this prevents the battery powering the reciever. Connect the battery to one socket and the servo to the other. Of course you will need a separate power supply to the reciever - say the BEC for the M-tronics unit.

If you are runnig a couple of these scottels, it may be a good idea to have a separate battery for each one - dependin on how much elastic-trickery they consume and how much the trackwork in the reciever can carry. A few more specs would help though.


Wom

Y leads work just fine and are available in "heavy duty" versions, leave it as is and most receivers will get powered from them with no problems, I use high torque servo's in two of my models and to keep the response speeds on the servos Y leads are the way to go.

As someone else stated, this omits the PCB bus track on the receiver for powering your servo.

The standard throttle servo can still be plugged into the RX with no problem.

Glenn