Model Boat Mayhem

Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: Nordlys on June 18, 2012, 06:47:31 pm

Title: Parallel connection
Post by: Nordlys on June 18, 2012, 06:47:31 pm
I want to connect two stick batteries with Tamiya connectors in parallel to supply the motor.
Could somebody please describe the connection procedure and what type of contacts I should use.

Thanks......

Nordlys..
Title: Re: Parallel connection
Post by: john44 on June 18, 2012, 07:58:21 pm
Hi N, what connector have you got on your speed controller?
If it is a typical Tamiya  Male type you can connect the batteries together by using a Y lead
with 2 male connectors to plug onto the batteries and 1 female connector to plug them to the ESC.
Either use a connector /chock block or solder the wires black to black,red to red.

john
Title: Re: Parallel connection
Post by: Martin (Admin) on June 18, 2012, 08:18:58 pm
I think you need something like this...
Title: Re: Parallel connection
Post by: Nordlys on June 18, 2012, 08:29:24 pm
Yes Martin, thats just what I need- Can you buy them made up?
John - the Esc connector is as you say a male Tamiya - I think Martins picture is the solution
Many thanks both.

Nordlys
Title: Re: Parallel connection
Post by: essex2visuvesi on June 19, 2012, 06:53:33 am
Im sure Dave at action has them
http://www.action-electronics.co.uk/stuff2.php
Title: Re: Parallel connection
Post by: ACTion on June 19, 2012, 08:19:36 am
We don't sell made-up parallel leads. In fact we don't recommend connecting two NiMH batteries directly in parallel at all. You would be better advised to use one of these, which has screw connections for the batteries and two soldered leads for the onward connection. Maximum current is 15A.
http://www.action-electronics.co.uk/pdfs/P103.pdf (http://www.action-electronics.co.uk/pdfs/P103.pdf)
DM
Title: Re: Parallel connection
Post by: petermun on June 19, 2012, 08:23:34 am
I use several of these ACTion units in my boats and they are good.   Pete
Title: Re: Parallel connection
Post by: Nordlys on June 19, 2012, 08:46:07 am
Hi,
Makes good sense- glad I posted about this! The output
from the board then would connect to my Esc. Is there a
connector for this with the ACTion item?


Thanks

Nordlys
Title: Re: Parallel connection
Post by: ACTion on June 19, 2012, 01:59:30 pm
Hi,
Makes good sense- glad I posted about this! The output
from the board then would connect to my Esc. Is there a
connector for this with the ACTion item?
No - you will need to fit a switch, a fuse and connectors to suit your installation.
DM
Title: Re: Parallel connection
Post by: Nordlys on June 19, 2012, 02:04:58 pm
Hi Dave,
Do you think that I would produce current higher than 15a when I connect two
7.2v nimh batteries in parallel to run a Graupner 9.6v motor?

Should I know how to work this out?

If not then I will contact you with a view to getting one of your parallel power boards.

Nordlys.
Title: Re: Parallel connection
Post by: malcolmfrary on June 19, 2012, 04:40:06 pm
If the motor is capable of pulling more than 15A, it will pull more than 15A, if the battery can deliver it.  If one battery can deliver 15A, and the motor wants it, that's what it will take.  Adding another battery in parallel will let it happen for longer.  If the battery can only deliver 10A, then two will be capable of delivering 20A, but if the motor "only" runs 15A, that is what it will take.
Different batteries have different current delivery abilities, the current taken by individual motors depends, among other things, on the load imposed by, among other things, the propeller.  So no pat answers or formulae, too many variables.  A meter is your best friend in cases like this.
Title: Re: Parallel connection
Post by: Nordlys on June 19, 2012, 04:54:22 pm
Thanks Malcom,
I'm really trying to determine what size fuse to build into
the circuit - knowing that the parallel board by ACTion
electronics is rated at 15a I suppose that will ,by default, be the fuse size?
Anything higher does not protect this board?

Nordlys
Title: Re: Parallel connection
Post by: malcolmfrary on June 20, 2012, 09:50:06 am
My inclination is to fuse below the rating of the electronics I am trying to protect, but as a last resort, i would look on the Action site and download the instructions for the particular item.
Title: Re: Parallel connection
Post by: Nordlys on June 20, 2012, 04:31:47 pm
The only current rating I've seen for this board is written in the post above - 15A
There's no rating shown on the link page which displays the board circuitry.?

So I take it as 15a or lower......
Its just that the fuse size I use in my boats is usually 20a as I use 25A Esc's
from Mtronics.
N
Title: Re: Parallel connection
Post by: Netleyned on June 20, 2012, 05:00:59 pm
The diodes in the parallel power board are 20 amp rated so that is why Dave is telling you to fit a 15 Amp Fuse.
If your motor tries to pull more than 15 Amps all it costs you is a new fuse.

Ned
Title: Re: Parallel connection
Post by: Nordlys on June 20, 2012, 05:44:51 pm
Thank you Ned, thats really all the explanation I need.
15A it will be./.....

Nordlys...