If they are the same as Doug posted a little while ago, they only show total volts for NiMh (only a pos and neg plug). The only way you could get individual cell voltage would be to have the cells wired similar to LiPos with check/balance wires from appropriate points, but I don't know if there are any checkers readily available. You could re wire a pack to a multi plug so you could check individual cells with a multi meter perhaps. Doug will probably have a better idea being the tech man. The problem with NiMh cells is there can be large numbers in a 'pack' (as against LiPos which have purpose designed chargers and checkers with JST-XH leads for 1-10 cells) and if there is a dud cell in the middle you won't know till the battery keeps dropping its' charge quickly when not being used.

".....If you are using NiMH or LiPo than I can also heartily recommend a little Capacity Checker/Monitor, available all over fleaBay for a few quid......The Checker can then tell you a bit more, e.g. if you've got a duff cell, which will collapse under load even if the other cells are still good!"

Interesting. But, as far as I can see, these checkers only provide total voltage for NiMH - just like a voltmeter. The individual cell info is just for Lipo or LiFE. Or am I reading their adverts incorrectly?

I heartily agree JB 👍
In fact you'll probably find that most commonly used 'inexpensive' (Chinese🙄) ESCs will only deliver 1 or 2A through the BEC.
Even folks like Action Electronics / Component Shop advise against using them with their modules.
No great demand around here for snow in June❄️
but if you'd like to check back around Christmas time .... 😀
Cheers, Doug 😎

Hi Doug, I always use a UBEC with power taken off before the ESC and disconnecting the BEC in the ESC if it has one. I fly planes as I've mentioned before, and most of us who do, don't trust the BECs in even the commonly used ESCs (maybe not the real expensive ones). They seem to have a habit of going up in smoke as they are mostly between 3-6A and it only takes a large servo jam up or similar to kill them, then kiss the plane goodbye. UBECs are available in much larger amperages as well to suit your max loading . I've never had a problem in around 12 yrs of electrics in planes and boats using this method, and you still have control even if the battery goes down to the minimum. (perhaps the ESC sucks too much power away from the BEC circuit trying to supply the greater demand of the motor in some low battery situations, thereby causing a lack of control,- ie motor,rudder, ie motor trying to go, but REC not getting power from BEC to tell it to, hence a stalemate,) - or in other words, the battery's too small for the job in hand. Selling snow to Eskimos, (sorry-Inuits) in your case, I know Doug, just my experience using UBECs.

My pleasure Ian,
If you are using NiMH or LiPo than I can also heartily recommend a little Capacity Checker/Monitor, available all over fleaBay for a few quid. See attached pic.
The car bulb trick is just to see how the battery reacts to a load.
The Checker can then tell you a bit more, e.g. if you've got a duff cell, which will collapse under load even if the other cells are still good!!
Happy sailing👍 Cheers, Doug 😎

Thanks for the reply Doug, I will use the idea of the car bulb to check next time just to see what is left in the battery.
Regards Ian

Thanks for the memory jog Martin,👍
Reminded me to finish my experiments with Voltage Comparator chips coupled to an external LED ladder or 555 based LED flashing unit as a 'Low Battery' warning!
Cheers, Doug 😎

"I had the rudder control on the Tx back to front ..."
He he😂 EXACTLY the same thing happened to me with my Sea Scout Ian.
Had to think backwards on her first run😮

Re BEC! That sounds very logical.
The internal regulator will need at least one volt more than the required output voltage (presumably 5V if it's like my 10A Vipers) to work.
Another reason I prefer a separate RX battery 👍
When you check a battery OFF LOAD it will always have recovered a little and show a slightly higher voltage than it would on load!
Check it when loaded with something like an old 5W car bulb and watch the voltage.
At 6V the current will be around 800mA.
The voltage will usually drop a little as the load is applied. But if it keeps on visibly dropping then the battery needs charging.🤔
Your motor will draw much more current of course, which accelerates the process.
All's well that ... 👍
Cheers, Doug 😎

Hi Will,
I too like the idea of having a separate battery for the receiver as in the past I have had a main drive battery get extremely low, and by leaving the boat bobbing about in the water for a while it just had enough charge to pulse it in to shore.
If the receiver was run from the BEC then I would not of had the power to do it.

Martin.

Martin, yes too responsive I intend to reduce the rudder throw.
Cheers Ian

Doug, yes I intend to reduce the rudder throw as it is to severe. However when I ran the boat in the video I had the rudder control on the Tx back to front which rather complicated matters. This is now reset. The speed controller is an Mtroniks viper marine 15 amp unit suitable for up to 12 volts. Unfortunately the motor is the original 6 volt jumbo 540 from the 1970s. I am running it on a 7.2 volt Nimh pack. I contacted Mtroniks and they said if the voltage to the ESC drops below 6 volts then the BEC will not work. I think under full load the voltage may drop to 6 volts but when I have checked the battery voltage after the problem occurs it is at 6.7 volts. Anyway putting the receiver pack in has solved the problem because when the main Drive battery has run down now the boat speed slows but control is maintained.

Hi,
She looks very responsive to the helm.
Nice job.

Martin.

Nice job Will, goes well too👍
I might be tempted to reduce the rudder throw though, seems a little twitchy when you put full rudder on.
What was the snag with the BEC? Never run across that before!
What was it's voltage and current rating?
Trust you disconnected the red wire from ESC to RX after fitting the RX battery 👍
Unless weight is an issue I prefer a separate RX battery anyway, leaving the 'drive' pack to do just the driving😉
Cheers, Doug 😎