Hi,
I was wondering if qould be possible to install separate switches to power on/off the computers and let the battery connect. This to avoid open the housing and disconnect the battery every time.
Have anyone tried that before?
@Elliott did you guys had experience with that?
If you mean a switch to power off all the 5v stuff yes I did this with their switch. I put it between the bec and tether interface boards positive rail. So basically only the esc’s have power, thought about a crydon 100amp SSR as I use them to control heaters in my customer heated 3d printer enclosure but not sure if the rov will push past 100amps even if just for a moment.
edit:
don’t be a goof like me put your switch on the outside holes so its easy to turn, my silly self put it on the middle holes on the 18 hole plate and its hard to turn.
Hi @rold,
I discussed something similar in this comment, which may be of interest. It’s not something we’ve done testing with, but it’s a decent idea for putting the vehicle into a low power state, as long as you remember to properly disconnect the battery before storage, to avoid it running down to unsafe levels.
This can also work, although it’s not quite as low power as the option I discussed, especially if there are many accessories in the vehicle (e.g. Ping360, Ethernet Switch, Lumens, etc).
It’s worth noting that given we recommend a 5V 6A regulator, and our Switch is only rated to 5A, it’s technically possible to supply more power than the switch is rated for in this kind of configuration. That said, the 5V components in a standard BlueROV2 setup are not expected to require more than 5A, so it should generally be fine unless using additional power-hungry 5V accessories.
Would something like this work for you? Adafruit Push-button Power Switch Breakout : ID 1400 : $5.95 : Adafruit Industries, Unique & fun DIY electronics and kits
I’ve started using it for some of my enclosed electronics using a magnetic reed switch inside the housing to activate. Seems to have very low power draw when off. Only downside I’ve run into with them is that they turn on as soon as input power is applied, so you end up having to power the system down when first setting up, or when depleted batteries start supplying power again during recharge (enclosed batteries).
It’s only 3A though, so if you have some high-draw electronics, you might need to have those go through a separate relay.
Hi all,
Not sure if this is the correct thread but I though that maybe is of your interest. Please @EliotBR feel free to move it if there is a more proper one.
We have build a MOSFET based electronic switch capable of handling more than 80A of load in a very small size. We install it in each battery housing (there are two in our ROV) and it is able to totally switch off the power using standard BR switch.
It is still pending to do a “burn” test to confirm the exact power rating but we have install them in 3-4 ROVs the last couple of years and have pushed them to the limits with no issues.
The plan is to open access the schematics but due to high power handling, we want to be 100% sure for its behavior in all possible conditions. It is based on dual “ideal diode” electronic design and the trick is to choose high power / low on resistance MOSFETs (hard to find these days) and to design the PCB in a way that minimize resistances, thus heat generation.
It also allows charging the batteries and with the combination of Cobalt connectors and pressure relief valves there is no need to open the battery housings at all.
(sorry for the pictures’ quality, I am far from the shop for getting better ones)
That is nice switch I would buy one if you sold them.
I will say having very personal experience with a lipo fire, that occurred after a charge had stopped and no more current placed into it, that they can catch on fire when everything is correct. I still use that charge today years later. I scoped the fireball of death smoke into a 50cal ammo box and ran it outside. The heat was incredible and the last thing I would want to do is have a fire inside of a tube regardless of pressure release, and if that tube happens to be acrylic could be more toxic.
