Vitron BMV-702

[capran]

Helmsman 38 with Vitron 3000 charger and inverter. Tried following a you tube video to program the BMV 702 monitor. Inputted amp hours of battery (820) but seems to stop there and doesn't follow the you tube video. But the main issue is the 702 and it's battery monitoring process. We have been attached to shore power with the charger on, but the BMV 702 does not seem to recognize the amp hours being charged. It only recognizes the amps being used and the amp hours total used. So, for example: hooked up power to the 702 meter 48 hours ago, and have the charger on all that time. But the 702 does show current amps and total amps (in 48 hours the fridge used about 109 AH) I am wondering if that is only a measurement of the outflow of AH used without taking into account the inflow of amps from charging, or could it be that the AH used is much higher and the AH being charged offsets some of that? I had a Link 20 on my sailboat and when we were charging at the dock or motoring, even with the fridge running, the AH used would work its way back from a negative number to a positive number ie lets say over 2 days we used 100 AH. would show up as -100. running the motor it would decrease -95, -80- and so on so that after a few hours, the number would be +2 AH, showing that all the AH used had been replunishished so the next time with the power off it would be starting a fresh set of 0 to know how much I was using. Is the 702 only going to give me a total AH used going forward, disregarding any charging going on?

 

[ksanders]

Helmsman 38 with Vitron 3000 charger and inverter. Tried following a you tube video to program the BMV 702 monitor. Inputted amp hours of battery (820) but seems to stop there and doesn't follow the you tube video. But the main issue is the 702 and it's battery monitoring process. We have been attached to shore power with the charger on, but the BMV 702 does not seem to recognize the amp hours being charged. It only recognizes the amps being used and the amp hours total used. So, for example: hooked up power to the 702 meter 48 hours ago, and have the charger on all that time. But the 702 does show current amps and total amps (in 48 hours the fridge used about 109 AH) I am wondering if that is only a measurement of the outflow of AH used without taking into account the inflow of amps from charging, or could it be that the AH used is much higher and the AH being charged offsets some of that? I had a Link 20 on my sailboat and when we were charging at the dock or motoring, even with the fridge running, the AH used would work its way back from a negative number to a positive number ie lets say over 2 days we used 100 AH. would show up as -100. running the motor it would decrease -95, -80- and so on so that after a few hours, the number would be +2 AH, showing that all the AH used had been replunishished so the next time with the power off it would be starting a fresh set of 0 to know how much I was using. Is the 702 only going to give me a total AH used going forward, disregarding any charging going on?

Perhaps the charge source does not go through the shunt.

I say that because if the shunt is reading discharge amps it should read charging amps as well.

 

[capran]

Perhaps the charge source does not go through the shunt.

I say that because if the shunt is reading discharge amps it should read charging amps as well.

WOW. I had not considered that, but it makes total sense. so now I need to figure out if there is a way to have it do both. I have no idea how long it takes to recharge underway but I guess an option would be to assume it's nearly charged up when I anchor, and just unplug and plug it back it which resets the amp hours used to zero, so that if I am anchored for a few days, I can at least keep track of how many amp hours I have consumed.