The T500 Thruster has a maximum operating voltage of 24 V. The T500 can also be powered using a 6S Lithium-ion/Lithium polymer battery (maximum). Continuous full throttle use should be limited to 1 minute or less when the T500 is operated at 24 V or with a fully charged 6S Lithium-ion/Lithium polymer battery to avoid overheating the thruster.
This suggests operating the T500 at its max 35.5lbf thrust for only 1 minute.
Question: What is the maximum continuous thrust the T500 can safely operate at?
Our thrusters are controlled using speed controllers, which do not technically directly control thrust.
I’m not sure if we have a definitive value for the maximum continuous speed command when using a 6S battery, so I’ve asked about that internally. Given the limiting factor is the thruster temperature, it likely depends on the temperature of the water it’s running in.
For some extra context, in our initial development testing we did successfully run a sample set of T500s at full throttle for an hour in 27℃ water, with a 22V power supply, but there were some issues with extended-duration full-throttle tests at higher voltages (hence the warning about extended full throttle at maximum operating voltage), and we don’t have statistically significant samples for longer full-throttle durations, or for extended durations in higher water temperatures.
There is some additional context and discussion about thrust at speed in this post, if you want to know more.
Hi, did you manage to do some more testing on the extended duration full throttle of the T500?
Our plan is to use 2x 24V 200Ah LiFePo4 and 4x T500 thrusters on an USV that is around 250kg max weight, so it is expected to move at least 1.5 h at max speed or close to max speed.
Could you recommend maximum power at which motors could be used for extended periods of time ?
Hi @Petar
Welcome to the forums!
Limiting each T500 to around 750 watts at that high voltage is your best bet for that application! If you’re operating in warm water (greater than 25C) you may need to reduce this…
Generally the T500 is not well suited for USV applications, as the nozzle adds significant drag at speed (it is intended for low speed, high force.) Removing the nozzle and using a prop like this may be a good idea - Blue Robotics is working on launching an M500 with corresponding prop for applications like yours!
Thanks for quick response Tony.
Maximum water temperature in which the motors would be operating is 30°C, average would be 25°C. Would you say that 500W limit on the power would give them long runtimes?
The plan was to test with and without nozzles since USV would be used in shallow waters with obstructions…
Hi @Petar -
Depending on your vehicle and power source, you may not even be able to achieve that power draw! But yes, 500W seems like a safe limit. In 24C water, at 4s voltages, towing a diver I typically see a max power draw of 740 watts, peak - from 2x T500s on the DIY DPV!
The nozzles are likely to cause more issues with entanglement of seaweed or other lines… protecting your props so they are not the lowest point of the vehicle can protect them from damage from impact, like the BlueBoat hull does!