Voltage issue found

Just curious; What was powered up when you measure a 0.2 volt drop from the battery to the acc bus
See there, told you I would be relying on your knowledge, I’m just a little hard headed. After looking again at the switches at the helm, I realized that the anchor light switch was on. Easy to do as it’s a three way with off in the center. Turning it off and like magic, I’m no longer wasting battery and my voltage at the battery matches the voltage at the helm panel. Thank you SS!
 
Memory was one of my guesses:) I feel better now...
As to the load, I knew it had to be something but to be honest, I would have guessed that the VHF was powered up.
Anyway, glad I helped a little bit.
 
Hello-
You posted this recently on a reply to someone and I am most interested. I am having trouble with my house batter (3 battery setup) not charging. Batteries are all new. There is an "isolating charging relay" installed. Battery charges fine when plugged into AC utilizing the onboard charger. But when not plugged in, 3rd (house) battery, which powers my sounder and chartplotter, goes down. Why does it not charge when engines are running?
Any suggestions or advice appreciated. Thanks

"Look into an AUX charging wire for your Yamahas. Most have a built in isolator for charging a secondary "house" battery. All you need is the right plug."
 
How is the third battery wired with respect to the other batteries? Is it wired in parallel to one of the other batteries? If so,it should charge when that battery charges but if the isolater is bad, it won't.
How many banks (separate charging wires) does the boat's battery charger have? 1,2 or more)
Can you tell where the connections to the isolater go?
Is your issue something new or has it been like that since you got the boat?
If battery 3 were disconnected, is it only the sounder and plotter that won't run or are there other devices ( which I suspect) that are not powered.

The point is that is is difficult to troubleshoot without knowing what is what.
 
How is the third battery wired with respect to the other batteries? Is it wired in parallel to one of the other batteries? If so,it should charge when that battery charges but if the isolater is bad, it won't.
How many banks (separate charging wires) does the boat's battery charger have? 1,2 or more)
Can you tell where the connections to the isolater go?
Is your issue something new or has it been like that since you got the boat?
If battery 3 were disconnected, is it only the sounder and plotter that won't run or are there other devices ( which I suspect) that are not powered.

The point is that is is difficult to troubleshoot without knowing what is what.

right. believed to be a new problem, but the boat is new to me. will be looking at the isolator and wiring today (supposed to stop raining). previous owner did not have problem, but was always plugged in. no power in my slip in marina. batteries are new. further research today--will check back with you. thanks.
 
got it figure out. isolator has a lockout feature that kicks in if battery voltage falls below 9.75. mine did, and hence, did not charge when motors were on.

thanks for input on this thread!
 
I am not sure I understand what is happening. Do you know the make and model of the relay? I would like to do some research.