I am curious if anyone has any experience with continuous operation of the T200 thrusters - as in, days / weeks at a time without a break. I understand there are a lot of variables to what I am asking, but let’s assume < 50% rated maximums - i.e., not constant full throttle, average water temps, etc.
I am specifically looking for a known life expectancy with continuous operation, or at least any issues that anyone has had related to the continuous operation of the thrusters. Even any MTBF (Mean Time Between Failures) specs for the motor itself would be most helpful.
You are correct there are a lot of variables that will greatly effect the longevity of a thruster in continuous use. Due to the nature of the marine environment and the many different use cases, its difficult to give an official MTBF rating to our thrusters. Sediment density, particle size, and composition is perhaps the greatest factor affecting longevity. In particular, a high density of ferrous particles in the water can clog up and potentially damage the internals of the thruster if not cleared out and cleaned regularly.
I can give you an couple example from my own experience. We have carried out some long endurance testing on an exemplar T100 from an early batch. This thruster was run at 50% throttle in a heavily chlorinated freshwater tank virtually nonstop for a little over four months total, with no signs of letting up. The main factor limiting thruster lifespan in most circumstances is bearing wear. We’ve estimated the bearings should last at least several thousand hours in ideal circumstances, and I believe this test demonstrates that.
Of course environmental conditions are still the number one factor, and can greatly affect this number.
@adam I completely understand and agree with the variability of use cases, environment, etc. and I very much appreciate your real world examples, that is exactly what I was looking for and gives me enough to go on in order to feel confident employing the T200 for our current project.
I anticipate 3 - 4 months of saltwater exposure at or around 50% throttle continuously beginning in late May / early June. I will report back with our results and a more detailed environmental report for that period upon completion…just to add to the real world data that you have at your disposal.
I have run several thrusters for a long time, both in seawater and tanks, on some robots we manufacture.
one of the robots ran 12 months continiously at 50% throttle, in a tank. (lightly chlorinated) Bearing wear got the best of one of the thrusters. it was stil running, but we decided to replace it as a precaution. the other 5 thusters are still going strong!
In seawater the story is a little different. on our robots that run continiously submerged thruster failiure happens after approximately 6 weeks. (one of 6 thrusters stop) The main causes are burnt stators. Rust in the rotor and around the bearing housing is also a major problem.
the thrusters never exeed 50% thrust. the power supply is 12V.
Water ingression in the enclosure happens from time to time, but i guess that belongs in another thread
propeller blades breaking from impact with objects (sticks, debris, seaweeds etc.) also happens from time to time.
the robots are never in contact with the seabed, or land/shore, so i guess that sediments is not that big of a issue for us. we do not see any kind of abrasion on the rotor/stator.
