Hi @JosephSmith, welcome to the forum! 
This is potentially contradictory - if the ethernet connection is lost and isn’t immediately restored once you stop trying to control the thrusters, then it’s quite likely the onboard computer has been provided with insufficient power and is in the process of restarting.
You could confirm this by seeing if the vehicle re-connects within the next several minutes, in which case some of these mitigation strategies may be worth considering.
In addition, I’d suggest looking into:
- The discharge current capacity of your power supply, and your onboard power regulator
- Our voltage drop calculator
- The technical details on the T200 product page, for expected current draw at a given voltage and throttle level
- Your other component current draws are also worth looking into, but the thrusters will typically have the biggest impact
There is some possibility it’s an electrical noise issue when the thrusters are running, but if the connection does not re-establish immediately afterwards then an onboard computer restart caused by insufficient power seems much more likely.