FXTI not charging battery in ROV

General Discussion
1

Hi, i am facing some issues regarding battery on the Bluesolutions ROV, currently error is low voltage failsafe in QGC.

Setup is

PC with QGC.

FXTI ( Blue box)

Bluesolutions ROV

Battery was suddenly flat, i charged the battery separately and checked the fuse in the FXTI, one of was triggered and i changed this one to a new one. Connected everything back and then everything worked, i let the ROV be on to confirm that the battery was actually charging but after some hours i lost connection to QGC and battery was flat again with minimum voltage.

Fully charged the battery and connected everything back but then ROV was working spontaneous, lost connection often with ROV/QGC. Checked the fuse again in the FXTI and one of them had been triggered again ( if this was the one that was changed in first time unfortunately i can not confirm..)

As of now i dont see any damage to the Tether cable. Does anyone have any suggestions to what i can do or what it could be?

2

Hi @212764607 -
Welcome to the forums!
Can you describe how you’re using the FXTI to charge the vehicle? This is NOT typically supported or accomplished… A wiring diagram and idea of what voltage you’re sending down the tether, and how, would be helpful! It seems like you’re saying you’re not able to charge the battery sufficiently via the tether? The FXTI does not have a fuse when sold by Blue Robotics?

3

Hi and thank you @tony-white .

Oh i tought that the FXTI supplied voltage to the battery in the ROV which charged the battery or how else would the battery charge?

230-240V contact from the wall which is connected to FXTI - USB from FXTI to PC - Tether from FXTI to ROV.

This is 1 out of 2 fuses thats in the FXTI.

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4

Hi @212764607
The Blue Robotics FXTI definitely does not have any intention to use AC voltage on the tether, or come with fuses like you show! You may find that the home plug module can send data over a line that is carrying such voltage, but it could be quite dangerous without proper safety systems. Can you share if your unit was modified, or purchased from another group? Is a charging circuit present in your battery enclosure? Without something to convert your AC voltage, a 220V AC supply will definitely not work to charge a DC battery!

5

Hi @212764607

Can you post a picture of your equipment? Especially the FXTI?

A regular FXTI doesn’t have those kind of fuses so I believe you’re describing something else or are dealing with custom equipment.

8

@tony-white @DanielG_BR Hi,

All this is supplied from BlueSolutions if anything has been done or modified i have no clue :frowning: . If any more details or pictures needed let me know, thanks. I am only able to upload 1 photo at a time since im a new user…

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9

Hi @212764607
That is definitely a non-standard, modified FXTI! The sticker, and the hot glue at the power cord penetration into the enclosure are the biggest clues. I’d be quite concerned if the only safety measures are the fuses on the AC power! A system like this should have an insulation fault monitoring system of some kind. The Binder connector is similarly not rated for AC high voltage… 175V max!

Can you please share a website or contact information for Blue Solutions? I assume they are not this distributor based in Germany?

If you can also share pictures of your subsea enclosure, and how that AC voltage connects, I’d like to better understand what additional (non-standard, potentially unsafe) modifications have been made…

It’s possible that your tether has been damaged, and the wires in it are shorting together - making an electrical connection where there shouldn’t be one. This would cause fuses to blow quickly though, which doesn’t match your failure.

Installing and sharing screenshots from the tether diagnostic extension would help to troubleshoot your network connection, as would a bandwidth test.

10

@tony-white it seems they’re this Norwegian company. They have an ROV product page with quite a limited description, so it’s not clear what kind of modifications may have been made.

Our FXTI product page shows the original product, without the mains power connection.

Given the limited details on the BlueSolutions website, I’m not sure what kind of technical details or supporting documentation you’ve been provided with, but our products have quite detailed specifications, which you may be able to refer to to determine at least any major differences. Our BlueROV2 product page and the accompanying assembly guide could be a good starting point, although you can presumably also ask the company you bought it from.

While this forum is not just for discussing official Blue Robotics products, it will be difficult for anyone to provide support for a product with unknown modifications, so if you’re experiencing issues with a custom vehicle then your first port of call should likely be whoever sold it to you.

We can presumably be more helpful when it comes to any unmodified components and software, but otherwise the best we can do is speculate from the information you’re able to share with us :slight_smile: