ESC and T100 Power Input

General Discussion
1

Hello my name is Julio and I was wondering what is the proper size fuse I should use for the T100 thrusters.

I plan on putting a 15A fuse in line on the positive terminal of the basic ESC and was wondering if that is too high and damage the T100 thruster since the specs say the T100’s are rated for 12.5A max. Or will the ESC make sure the T100 never receives more than 12.5A? Below is more information on what I plan to do.

Battery
-12 V

  • 35 Ah
  • just one of these batteries

T100 Thrusters

  • 4 X T100 thrusters (running for a few seconds all together at a time)
  • In parallel to battery
  • each one will have a fuse on their positive terminal of ESC

Tether

  • 25 feet one way (50 feet total)
  • 10 AWG

My friends working on this project to build a submarine told me there was going to be 2.5V voltage drop meaning we would have 9.5 volts to work with. Since Power = Voltage x Current we would need 14.21 amps to run the thrusters at max (135 watts), but that is past the 12.5 amps max rating for the thrusters is this okay?

2138×2851 2.09 MB

2

Hi Julio,

If you have a 2.5v drop in the tether cable, that will actually decrease the amount of current that the thrusters use. As the voltage is decreased, the thrusters are able to draw less current. So, for instance, at 9.5v, I think you may only be able to reach 10A or so per thruster. In that case, I think the 15A fuse will work well.

We don’t put fuses on our ESCs very often. The ESCs can draw more current very briefly when starting and stopping the motor, so if the 15A fuses blow you might need a little higher.

Hope that helps.

-Rusty