All donations are securely managed through PayPal. Amounts donated are not published online.
Many thanks for your kind support.
Model Boats Website Team
Donation History
April 2018: 19 people March 2018: 13 people February 2018: 8 people January 2018: 25 people December 2017: 7 people November 2017: 13 people October 2017: 9 people September 2017: 6 people
I apologise if this has already been covered here but I am now at the point of installing the motor in my new model. The motor is a Graupner speed 600, and the specs are : Nominal voltage 8.4 V Operating voltage range 4.8-9,6 V No-load rpm 15500 No-load current drain 1.8 A Current drain at max. efficiency 11 A Current drain when stalled 70 A Max. efficiency without gearbox 75 %
If I use 8.4 volts what size wiring do I need? Do I need to cater for the 70A current or the 11A current, or somewhere in between, with a fuse? Sorry to be a bit dim on this but I am confused (with most things these days!)
Hi Chris, no you don't need 70A wire! 😊 That might be horribly thick and stiff for a scale boat. You need wire the same size as probably on both your motor and battery. Same the 'standard' wiring in cars. Available I suppose at Halfords and any car diy shop. WHAT YOU DO NEED IS A 15 OR 20 Amp FUSE TO PROTECT THE WIRING IF THE MOTOR STALLS (PROP GETS BLOCKED) 😡 If your ESC has a BEC supply for the RX put the fuse in the positive motor lead, probably red or yellow. If not, i.e. you have a separate battery supply, put the fuse in the positive lead from drive battery to ESC. Then at least the RX will still work and maybe you can see from shore if it still responds; e.g. by switching on lights or some other visible function. With twin or more props fusing the motor wire itself can sometimes help get the boat home on a remaining engine. Somewhere in the Electrical stuff blog is a long discussion on the subject! Have a look here https://model-boats.com/forum/electrical-related/28332 "What type of wire?" Happy sailing 👍 Cheers Doug 😎 PS: Almost forgot, if you have a brushless motor you have no choice but to put the fuse in the positive wire from battery to ESC! Brushless ain't got no positive!
Young at heart - slightly older in other places 😉 cheers Doug Grant me the Serenity to accept things I can't change, the Courage to change things that I can, and the Wisdom to know the difference!
Hi Neil, I noticed that you've had a look at the extensive Electrical Blogs about wire thicknesses from a month or so back, so maybe you found the answer, if not- Use flexible multi-strand wire with a cross section area of about 0.75 mm². Don't get the +s and -s of the exciters mixed up or they will work 180° out of phase and dampen the volume.
BTW: the exciters are not transponders! Transponders are devices which respond to a particular input signal by sending a signal back. Such as the transponders in aircraft; they respond to secondary radar signals by sending back their ID and location, height etc. Or ship's SAR beacons which respond to a 9GHz search radar by sending back ID and location coordinates. The exciters are actually transducers which take an input signal in one form and convert into an output signal of a different form; e.g. here electrical to mechanical! Here endeth the lecture for today! 😉 Happy modding, Doug 😎
Young at heart - slightly older in other places 😉 cheers Doug Grant me the Serenity to accept things I can't change, the Courage to change things that I can, and the Wisdom to know the difference!
Or concentrate everything in the Build/Upgrade blog?
Young at heart - slightly older in other places 😉 cheers Doug Grant me the Serenity to accept things I can't change, the Courage to change things that I can, and the Wisdom to know the difference!
Neil If you want to ask a question the Forum is the correct place. Your build blog is for describing your progress and may not be seen by all members who are not subscribed to your blog.
Young at heart - slightly older in other places 😉 cheers Doug Grant me the Serenity to accept things I can't change, the Courage to change things that I can, and the Wisdom to know the difference!