Model Boat Mayhem

Mess Deck: General Section => Beginners start here...! => Topic started by: boxer on August 26, 2018, 05:26:45 pm

Title: How to work out wire size needed
Post by: boxer on August 26, 2018, 05:26:45 pm
so I have 15 amp viper marine esc


540 motor


Which wire to use to join from motor and esc and how to work out load


Do you solder to motor or use connectors ?


New to this and couldn't find a an answer through search







Title: Re: How to work out wire size needed
Post by: dougal99 on August 26, 2018, 08:30:02 pm

Assuming an ordinary DC motor. You need to determine the stall current of your motor. This is the maximum current the motor will demand. To do this you need to clamp the motor, in a vice for example, connect it to a battery with an ammeter in the circuit. Run the motor and then using a padded pair of pliers grip the output shaft until the motor stops turning. quickly read the amperage and let go. You can damage the motor if it is kept stalled. The required capacity
of
the wiring can then be determined. It is also advisable to fit a fuse with a value below the stall current.


I solder my wire to my motors. Less likely to come free.


HTH
Title: Re: How to work out wire size needed
Post by: CGAux26 on August 26, 2018, 09:34:01 pm
I am into a build with two 540 motors.  Running on 6 VDC, I have 20 amp fuses on each motor/ESC.  Used 16 gauge stranded silicone insulated wire (it's very flexible) You can find tables of amperage vs. wire size online. 



I soldered short wires to each motor, then added Power Pole connectors at a convenient place in the wire run from the ESC's.  On previous boats I have used push connectors at the motor terminals and bullet connectors instead of Power Pole.  Some folks like JR or Tamiya connectors.  Avoid having to disconnect your wires from the motor itself for maintenance.  Those little tabs can break off easily, then it's OH SH.. time.
Title: Re: How to work out wire size needed
Post by: Colin Bishop on August 26, 2018, 10:26:04 pm
If the motor is new then it may state on the box what the stall current is or there is sometimes a label on the motor itself.


Colin
Title: Re: How to work out wire size needed
Post by: derekwarner on August 26, 2018, 11:38:20 pm
extract from Google ....RS540 Motor specifications....hungry eating devils  O0



       
 Model  : RS-540 12V   Weight  : 5.4 oz 
 Operating v  : 4.5v - 12v   Length of motor  : 1.97 in 
 Nominal v  : 12v     
 No Load RPM  : 17200   Diameter  : 1.41 in 
 No Load A  : 1A   Shaft Diameter  : 0.125 in 
 Stall Torque  : 32.64 oz-in   Shaft Length  : 0.3 in 
 Stall Current  : 37A   Mounting Screws (2)  : M3 
 Kt  : oz-in/A     
 Kv  : rpm/V     
 Efficiency  : 70%     
 RPM - Peak Eff  : 14840     
 Torque - Peak Eff  : 4.47 oz-in/A     
 Current - Peak Eff  : 5.85A   
Title: Re: How to work out wire size needed
Post by: BrianB6 on August 26, 2018, 11:49:57 pm
There are many varieties of 540 motors.  It is only a size
I managed to get 2 very efficient ones for my corvette so it pays to check the specs. if possible.
Others as Derek mentions eat controllers for breakfast.  <:(
Title: Re: How to work out wire size needed
Post by: derekwarner on August 27, 2018, 12:06:10 am
Yes .....apologies.....need to know the number of turns <*<    or segments [nothing to do with Egyptian turns.......they probably indicate wire looms]

There is always a reason these motors are about 2/6'd each
Title: Re: How to work out wire size needed
Post by: justboatonic on August 27, 2018, 12:50:01 am
Ugh. Please dont use Tamiya type connectors. Not only are they cheap and nasty rubbish but they are very inefficient.  If you can solder (not hard) solder wires onto the motor from decent connectors like deans, hxt's or gold pin and tube.
Title: Re: How to work out wire size needed
Post by: Peter Fitness on August 27, 2018, 06:44:06 am
I'm a big fan of Deans connectors and use them exclusively. I too agree with soldering the wires to the motor, it's a very secure method.


Peter.
Title: Re: How to work out wire size needed
Post by: malcolmfrary on August 27, 2018, 08:53:23 am
so I have 15 amp viper marine esc


540 motor


Which wire to use to join from motor and esc and how to work out load


Do you solder to motor or use connectors ?


New to this and couldn't find a an answer through search
Look at the wire on the ESC.  Use similar.
Soldering is the only secure way to connect to the motor unless it is some type with proprietary connectors.  But all the model motors that I've seen have solder tags.
Title: Re: How to work out wire size needed
Post by: john44 on August 27, 2018, 08:58:26 am
I to am a fan of deans connectors, but make a adapter for deans to tamiya so you can
Test the esc,s work correctly as cutting manufacturers plugs off to fit your preferred
Connectors will affect your guarantee if you find a fault.


John
Title: Re: How to work out wire size needed
Post by: steamboat66 on August 27, 2018, 11:52:48 am
i use XT60 connectors
Title: Re: How to work out wire size needed
Post by: Klunk on August 27, 2018, 12:07:18 pm
deans or xt60. wire i use house wiring. that's rated at 240v 32amp.