what is the best wire/size to run?
7 feet from t200 to (blue robotics)-esc and
7 feet from battery to (blue robotics)-esc
thanks
Hi @catdog, welcome to the forum 
At times like these, our voltage drop calculator is a valuable tool to understand the different factors and determine the consequences of a given decision.
You can also use it to work backwards from a set of requirements (e.g. if you want to run the thruster at a given voltage and its corresponding current, which you can find in the product technical details, then you can use that to determine an expected voltage drop over your cables, and your required cable gauge / battery voltage).
yes,but can you answer my question.
thanks
steve
Hi @catdog -
Generally you want to keep the wires from the motor to the speed controller as short as possible - 7 feet may work, but if you have issues with running the motor at low speed or max speed, it is likely due to this wire extension.
The T200 wire size is 16AWG, and it is carrying 3 phase power. So using the calculator Eliot shared:
It’s important to note that technically the power from ESC to T200 is AC, not DC, which the calculator doesn’t yet support. However by putting 3 conductors in parallel, we get a rough approximation that shows that sticking with 16AWG should be ok.
For the power wires from the ESC to the battery, you want to use enough copper to avoid significant voltage drop, as that is energy lost to heat rather than pushing you along!
12AWG wires for positive and negative should keep your loss to ~5%. You’ve not shared what voltage you’re powering the system with, which is a critical factor - so please use the calculator to accurately predict what voltage drop you’ll have!
it would be better to know what all of the above means.
got any videos or literature on the subject?
Which part(s) / terms are you unsure of?
You could try reading some introductory electronics material (including tutorials or textbooks), but that’s not very specific.
If there’s something you’d like clarified then feel free to ask about it, but broad questions will get broad answers - we can’t read your mind!
Hi @catdog -
The Thruster Commander and ESC should be with your controls in the green control box. It looks like you’ll be able to manage shorter than 7’ cables between the elements?
Using a higher voltage battery will give you a higher maximum thrust. LiFePO4 batteries may not be able to source 30A continuous, but 24V versions are available. The T200 cannot be operated at full throttle at the higher voltage for long - see the product page FAQ for more details.
From an electrical perspective you want to minimise the wire lengths of any high current usage, and of any timing-sensitive digital signal cables, so you’d ideally want the thruster commander and ESC to be located together, and between the battery and the motor.
From a waterproofing and reliability perspective it may be challenging to have the control electronics right at the motor, so in the same space as the battery is likely easiest, assuming everything fits in the space you have (/can make) available.
It should be ok to have longish signal wires to the potentiometer and the switch input, as long as the wires are appropriately waterproofed (they’ll stop working properly if the resistance gets too high from corrosion).
would this work?
Dakota Lithium 12V 54Ah Deep Cycle LiFePO4
the following is from the specs for this battery:
Discharge
60A max continuous, 100A max pulse 10 second pulse.
is there a difference between continuous and max continuous?
Hi @catdog -
That battery should be about to run a single thruster just fine. It should also run two at full throttle continuously. The battery is rated to provide 60 amp continuously or 100 amps for 10 seconds, there is no “max continuous” beyond 60A.
does anybody use a quick disconnect (three way plug )between the motor and the ESC?
and what type of plug?
thank you
Hi @catdog -
Blue Robotics will have an affordable solution for this someday, but in the meantime, you can retrofit a cobalt connector from Blue Trails Engineering onto your thrusters to disconnect them. This connector cannot get wet when unplugged, and uses potting which must be done well to work!
@catdog I came across this relevant video you may be interested in!