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[newbybuilder]

Hi, can anyone advise????

I'd like to parallel 2 x 6v batteries for a longer running ability, im running a speed controller/ mixer for throttle and steering via 2 motors, im told i need a Schottky diode to protect the esc!!!

can anyone tell me where id find a wiring diagram and a supplier, 2 x 6v 4amph batts, feeding a pair of MFA torpedo motors.

Regards
N

[nhp651]

haven't a clue what a schottky diode is.............never heard of one..........

but the usual way of protecting your ESC's is by putting an inline fuse into the positive wire from the battery to the ESC with a fuse a little lower than the rated continuous rated draw of the motor/esc related figure giiven for the esc. (not the stall draw)......this should be fine for what you want with a torpedo motor.....I've never had any problems with this arrangement.

neil.

[Tug-Kenny RIP]

I believe the Diode protects each battery from each other, rather than further down the line towards the Esc.

Neil's advice holds for the general circuit. What batteries are you using ?   If it's the Lead acid type then,  couldn't you fit a larger amp/hour one instead.  As a note, there is not too much to worry about when fitting these in parallel.  Other types of battery do go mad if one is of a higher voltage  however,  hence the need for diodes in the line to protect the 'back EMF'  (electro motive force)

Hope this helps

Ken

[tr7v8]

Doesn't need a schottky diode particularly but you should have a diode in each lead, not to protect the ESC but to stop circulating currents between the batteries. A standard 1N400x will do where x is at least 1.5 times the max current you'll pull.
Corrected as I've just looked at Maplin & Schottky diodes have come down in price big time & would give less voltage drop across them. I'd suggest 10amps or so would be OK unless you're running massive props & performance. This is the spec sheet of a 16A one which is sensible money, won't need a heatsink. You'll need one in each battery power lead facing the right way. I'd run a fuse in each battery lead as well as close to the battery as possible.

http://www.maplin.co.uk/media/pdfs/Module%2046431.pdf

[john s 2]

You could speak to Dave at Action electronics. I believe he can advise and sell you what you need.John.

[riggers24]

Off the ACTion website

P103 PARALLEL POWER BOARD
£ 14.50 Incl VAT   
This simple little board has a dual 20A Schottky diode and heat-sink. It allows the safe use of two equally-rated batteries, wired in parallel for increased capacity and therefore longer running times, by eliminating the risk of dangerous "back-charging" from one battery to the other.

[malcolmfrary]

Schottky diodes have a different construction to normal semiconductor diodes that allows them to switch on and off faster.  Sounds cool and geeky if dropped into the conversation, especially if neither party in the conversation knows what one is.
As a safety device to prevent circulating currents when paralleling batteries they do a great job as suggested above, as is the fitting of fuses between battery and ESC.  They can also be used to soak up back EMFs coming from a UNIDIRECTIONAL motor since the very short switching time diverts the power before it has time to damage the ESC output components.  Most present day ESCs using FETs have internal circuitry intrinsic to the FETs that act as diodes to direct excess back EMF energy back into the power leads.  You do still need regular suppression.
All this only applies to brushed motors, like the ones in the OP.

[newbybuilder]

Thanx for all your advice,

ACTion electronics P103 is the answer.

N

[irishcarguy]

You guys just confirmed the reason anybody running model boats should be a member of this forum, I am dumb when it comes to electrics so it fascinates me when I see what some of you guys can sort out & without missing a beat, I am impressed. Mick B.