Model Boat Mayhem - Forum

Technical, Techniques, Hints, and Tips => DC Motors (Brushed) and Speed Controllers => Topic started by: ajb63 on February 01, 2018, 10:26:31 AM

Title: Bowthruster Wiring
Post by: ajb63 on February 01, 2018, 10:26:31 AM
Hi, I am building Model slipway 1/16 Tamar and need help on wiring the Raboesch bowthruster brushed 400 motor. My main motors  are brushless with 2 x 5000mah 11.1v lipos. I don't know if I can take the power from one of the 5000mah batteries and put it through a voltage regulator to 6-7.2 volt then to a brushed regulator. Or what are my other options . Have looked on the forum pages and can't find find any info to help. This is my first model in radio control.  Thanks in advance. Alan
Title: Re: Bowthruster Wiring
Post by: Stavros on February 01, 2018, 10:45:42 AM
You could do what you suggest but my preferred route would be a 7.2 stick pack and a speed controller for it....now whatever route you take just remember that you need to disconnect the red lead in the esc lead from the controller otherwise you will pop the speed controller also if you have twin motors on it you also need to disconnect one red wire as well....


Dave
Title: Re: Bowthruster Wiring
Post by: ajb63 on February 01, 2018, 11:31:57 AM
Hi Dave.
I realise I have to disconnect one of the red wires from the 2 main brushless motor before the RX . Are you saying i also have to disconnect the red wire from the brushed esc. Should I look for a brushed esc with or without bec  or is there no difference .
Alan
Title: Re: Bowthruster Wiring
Post by: inertia on February 01, 2018, 11:45:53 AM
Alan
This one is just the job for that job. It runs equally in either direction, will handle 10A continuous and has no BEC to worry about. https://www.componentshop.co.uk/p79-condor-10-2-autoset-computer-speed-controller.html (https://www.componentshop.co.uk/p79-condor-10-2-autoset-computer-speed-controller.html)
DM
Title: Re: Bowthruster Wiring
Post by: Stavros on February 01, 2018, 11:58:56 AM
Another Dave beat me to it  baisically if the esc has Bec then Yes but the one that Inertia has reccomended you DO NOT have to dissconect the red wire


Dave




Title: Re: Bowthruster Wiring
Post by: McGherkin on February 01, 2018, 12:54:08 PM
I am doing what you alluded to in your original post.


A regulator, something like one of these:
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F322552610733 (https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F322552610733)


And then just a 7.2v ESC (A Viper 15 in my case).


The setup is lighter than carrying a second battery and makes things simpler for charging.
Title: Re: Bowthruster Wiring
Post by: ajb63 on February 02, 2018, 02:32:21 PM
Hi DM
Does the Action P79  controller require the battery power to be lowered to 7.2v the same as output to bowthruster motor . Or is it calibrated in the P79 unit from my 11.1v supply. Thanks
Alan
Title: Re: Bowthruster Wiring
Post by: Tug Fanatic on February 02, 2018, 02:43:52 PM

Hi DM
Does the Action P79  controller require the battery power to be lowered to 7.2v the same as output to bowthruster motor . Or is it calibrated in the P79 unit from my 11.1v supply. Thanks
Alan


Another entry in the "worlds smallest font" competition.


Does anybody know why these keep occurring?
Title: Re: Bowthruster Wiring
Post by: ajb63 on February 02, 2018, 03:18:53 PM
Text was from my tablet .
If it happens again l will try laptop.
The text size actually reflexes my true knowledge of electronics.
Title: Re: Bowthruster Wiring
Post by: ajb63 on February 02, 2018, 03:28:10 PM
Hi DM
Does the Action P79 controller require the battery power to be lowered to 7.2v the same as output to bowthruster motor. Or is it calibrated in the P79 unit from my 11.1v supple . Thanks

Title: Re: Bowthruster Wiring
Post by: McGherkin on February 02, 2018, 04:22:34 PM

Another entry in the "worlds smallest font" competition.


Does anybody know why these keep occurring?

It's a bug in the forum, I think after posting URLs, deleting some text or going back from bold or something like that. I've not tested it enough to pin it down to what exactly.

For those wondering what it says...
Quote
Does the Action P79 controller require the battery power to be lowered to 7.2v the same as output to bowthruster motor. Or is it calibrated in the P79 unit from my 11.1v supple .
Thanks Alan

Looking at the sheet for the P79 it does not look like it will modify the input voltage at all, so you should feed it 7.2v.
Title: Re: Bowthruster Wiring
Post by: Netleyned on February 02, 2018, 04:26:52 PM
I have had the same when I
have pasted something.
Ned
Title: Re: Bowthruster Wiring
Post by: inertia on February 02, 2018, 06:43:21 PM
There are several score (if not hundreds) out there doing this very job with MS Tamars all round the world.
P79 does not reduce the voltage from the one input i.e. if you want 7.2v output then you need a 7.2v battery in. The weight of a separate 7.2v Sub-C pack in this model should be no problem - the hull is a big as a baby bath.
As for the 3-pin lead, you just plug it into the receiver and it will autoset the neutral signal every time you switch on, so there's no need to muck about with flashing LEDs and Tx stick movements.
If you want a speed controller that will take in 11.1v and put out 7.2v then you need a P93 running on 50% ESC mode. That's as close as you'll get.
(Please no comments about my arithmetic - note the phrase "as close as you'll get" before hitting the Send key).
DM
Title: Re: Bowthruster Wiring
Post by: McGherkin on February 02, 2018, 07:14:40 PM
The hull might be big but from all Iíve seen the weight tolerance is quite tight. Plus, the simplicity of only having one battery for the model says a lot!


Thatís my reason for using a regulator.
Title: Re: Bowthruster Wiring
Post by: inertia on February 02, 2018, 08:53:29 PM
OK, OK - what the hell do I know anyway?
The delight with these forums is that you can do just what you like in the end.
I'm outta here to move house. See you some time.
Maybe.
DM
Title: Re: Bowthruster Wiring
Post by: McGherkin on February 04, 2018, 12:41:10 AM
OK, OK - what the hell do I know anyway?
The delight with these forums is that you can do just what you like in the end.
I'm outta here to move house. See you some time.
Maybe.
DM

Slightly disappointed that my last post on this issue was deleted... perhaps accidentally? It gives a bit of clarification that no ill harm was intended.

Anyway, to reiterate;
Plenty of ways to skin the cat, I'm not making a personal dig or anything like that so please don't feel offended. Just giving my reasoning for the way I've done it :-))
Title: Re: Bowthruster Wiring
Post by: ajb63 on February 08, 2018, 11:48:26 AM
If l go for a separate NiMh 7.2v battery pack . Can l get away with 2000mah or 3000mah size battery to run the bowthruster .Thanks for any replies.
Title: Re: Bowthruster Wiring
Post by: McGherkin on February 08, 2018, 01:44:58 PM
Either should be plenty, considering a bow thruster only uses a few amps youíd struggle to wear the battery out in any short period of time.