T500 - Suggested max PWM if running at full throttle?

Blue Robotics Products Thrusters and Motors
1

Hello,

I am in the process of building a USV with Blue Robotics products for the navigation system. The USV will be used by many different people with the company so I was thinking to set a max PWM as I am sure my colleagues will be running at full throttle regularly to keep the thrusters from overheating
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Is there a max PWM that is recommended for the T500’s when being used with 6s batteries?

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Hi @SweUSV,

That’s dependent on what the limiting factor is - be it the battery current output capacity, the current throughput capacity of the wires / power sensing components / ESCs, or the thrusters themselves.

Given you have specifically mentioned you want to avoid the thrusters overheating, I’ll assume you have already determined / designed a sufficient power system for your vehicle, and are just wanting to avoid high throttle usage overheating the thrusters, as warned about in the T500 product page:

We don’t currently have specific guidance for limits beyond that note, but the maximum continuous PWM would depend on the maximum water temperature you’re expecting to operate in (e.g. in very cold water, thruster overheating is less of a concern). If you can provide some more information about your operating conditions I can try to ask our R&D team for some relevant guidance, although it’s possible we don’t yet have detailed testing information for where that limit should be.

1 Like
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Hi Eliot,

Thanks for your reply.

I am using the Navigator, QuicRun 8BL150 ESC’s and the T500’s.
All extra cables are 10 AWG.
I am using 6s batteries.
I am located in Sweden and the water temperature ranges throughout the year from 2C/36F to 20C/68F.

I have previously used a USV with T200’s which we had some overheating issues with that we finally figured out that it was the 5s batteries that were providing too high voltage when fully charged. When using the old USV we would survey at ‘full speed’ for long periods which I am hoping to avoid doing now that I am using the T500’s. I am however concerned that if we have to do a transport to a survey area that running at full PWM’s for too long will damage the cores.

Just trying to make sure I’ve thought of everything.

Thanks for the help and let me know if you need any further information.

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Hi Eliot,

Were you able to get any feedback from R&D about this question?

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Hej, sorry, no response yet - I’ve just followed up.

It may be difficult to provide guidance for ESCs we’re not familiar with, but hopefully there’s an equivalent current usage or something that we can provide :slight_smile:

Note also per our general longevity guidance, that:

If you’re doing long operations in water with many particulates (and especially iron-rich ones that can get magnetically pulled into the rotors) there may be reduced capacity for
recommended maintenance, which could impact lifespan from factors unrelated to the power supply.

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Tjenare Eliot,

I will end up switching to the Basic ESC 500 so that the entire navigation system is Blue Robotics if that makes it easier for the R&D to respond.

I have a spray bottle with fresh water that I use to rinse the thrusters with after usage in salt water. I also try to remove the rotors to check for damage/cleaning somewhat regularly (once a week if using daily).