Adding a volt meter to the Rad Rover battery?

syl3

New member
Joined
Jul 15, 2020
Messages
10
Points
1
Does anyone know, is the charge port a good place to tap a volt meter on a Rad Rover battery. My other thought is at the headlight power cables may work, then you could just turn on the headlight to check voltage. Unless the voltage is stepped down at the headlight possible to usb 5v. I will check when I get a chance.
 

watts888

New member
Joined
Jul 13, 2020
Messages
9
Points
1
I just ordered a couple of voltage displays to mount on my 'dashboard' and plan on plugging them into each battery's charging port. Simply unplug it and plug in the charger when it is time for a charge.

 
Last edited by a moderator:

pete

New member
Joined
Jul 8, 2018
Messages
14
Points
0
I ordered this one, it has a really cool display showing either voltage or percentage.

 

syl3

New member
Joined
Jul 15, 2020
Messages
10
Points
1
Thanks guys, it will be great to see the actual voltage on the fly :)
 

watts888

New member
Joined
Jul 13, 2020
Messages
9
Points
1
I can report that the charge port does not show the voltage of the battery, it is connected through the BMS (battery management system) and only shows a low voltage. My voltmeter will be here tomorrow I believe, next I will look at the front light, for measuring voltage. I don't really want to cut into the wiring at the battery or battery mount as this may void the warranty.

I tested with a plug that fits the terminal, and the voltage is about .1v. I used to make camera parts so I have good collection of different plugs. This does not surprise me as this is an intelligent battery with a built in balancer and thermal protection using a BMS logic board. It is not connected directly to the cells. If it was then you would need a balance port and a n intelligent charger/balancer.
 

pete

New member
Joined
Jul 8, 2018
Messages
14
Points
0
I build custom lithium battery packs of all chemistries. The bms controls the ground side of the pack using mosfets as the switch. It is either open or closed based on cell voltage, current and temperature. No or low voltage at the charge port would indicate an open circuit. How does current from the power supply flow in an open circuit? Right it doesn't.

You should be able to get a pack voltage reading from the headlight terminals.
 

watts888

New member
Joined
Jul 13, 2020
Messages
9
Points
1
Volt meter installed, on the head light circuit. Works great, just turn on the headlight and I get a voltmeter reading. I only want to take readings now and then to get an accurate reading of power left. This works perfectly.

Once again the charge port on the Rad Rover does not give a reading of Lipo voltage. This is actually neater, no need for a switch. It was easy to solder the wires on the connectors, piggyback to the original connectors after removing a little of the heat shrink tubing. And then reinstalling new heat shrink and zip tying to original harness.
 
Top