I have done some reading on these forums regarding the operational temperature, and have discovered that 0-40 degrees C would be the only recommended temps, anything over that will start to heat up the internals and the Blue will start to see performance issues and possible serious problems regarding the raspberry pi etc.
To confirm - is it a complete no - go to operate the Blue in 70 degree C water?
Our BlueROV2 technical details actually recommend 0-30℃, which is also the case for our sonars, and the “Tested Cables” table for our WetLink Penetrators recommends 50-60℃ max (depending on the cable). Our battery safety information recommends 50-60℃ max (depending on the battery chemistry).
Our ratings and recommendations for things like temperature ranges are generally based off what we’ve tested to (with success, not to failure). Accordingly they’re not a guarantee that things will instantly break or stop working if they’re exceeded, but we also provide no guarantees that things will continue to work (as normal or at all) outside those conditions, and it may be dangerous to do so.
We can’t stop you from running tests if you consider it worth the risk, but 70℃ is definitely outside our recommended operating conditions, and at a minimum standard performance would not be possible. If you decide to do so, and assuming there are no hardware failures,
it is advisable to use an alternative power supply, and minimise thruster usage
the sensor readings would have reduced accuracy
the lights would likely throttle, and not be able to shine as brightly
the Raspberry Pi would throttle unless maybe if it was running only a very light load
it may help to
disable all but the absolutely essential services,
possibly reduce the video resolution and/or framerate,
install a small fan to circulate air within the enclosure
EDIT: I’ve just been informed that the magnets in the thruster rotors will start to get permanently damaged above ~65℃, so you would likely also need different thrusters lest they become a short-lived consumable.
As always I thank you for your incredibly well detailed reply. That has given us a much greater understanding of the parameters of the blue and we are now in a much more well informed position when it comes to liaising with the potential client.