Amp Hrs used steadily increasing despite solar panel.

[macbeth]

I have a Starter Battery (SB) and a House Battery (HB). I also have a Solar Panel which normally produces about 3amps when HB is discharged. I also have a battery combiner connecting SB and HB.

The Soar Panel is connected to the HB.

I've noticed the SB battery is steadily showing on the Battery Monitor an increasing amount of Amp Hrs having been used. Normally, the Monitor shows a discharge of 0.1 Amps for the SB (why I don't know, for it is a two circuit system, and everything on that circuit is switched off when I am sailing). However, for example, today, a nice sunny day, the battery monitor showed no current going to either battery, although the monitor showed - 19AH for the SB, and -0.3AH for the HB. No current going to the HB I was not surprised at, but why was no current going to the SB if it REALLY was discharged by 19AH ? Is the combiner not working ? Should I connect the Output from the Solar Panel to both batteries ?

[skipmac]

More details please.

- What brand/model of battery monitor do you have. All the ones I am familiar with only monitor amps in/out for one battery and voltage for the other. So standard setup, monitor amps on the HB and voltage on the SB. Are you sure you're seeing amps on the SB?

- Wiring diagram? So many things could be happening depending on how all this is wired together.

- Is there an isolator, Echo Charge, diode or something separating SB and HB? If both batteries are connected to the solar panel then the batteries are paralleled and both batteries feeding the house loads unless they are somehow isolated from each other.

Lots more but this is a start.

[skipmac]

I see you mention a combiner. Sorry I missed that. What brand and how is it wired in? On a sunny day what voltage do you see directly at the output of the solar panels. Then voltage at the solar charge controller? Then voltage where the solar panel controller connects to the HB and then at the SB?

[macbeth]

The Monitor is a 15 year old Link 20. Still working well. Monitors two battery banks. Push SB or HB and read V, A, Ah used, Time remaining for that battery. Actually the time read-out changes to CCCCC if the battery in question is being charged. That wasn't happening for SB either.

The combiner is also a 15 year old one from West Marine.

The main battery switch is a dual circuit switch, i.e. it has the SB and HB attached to different terminals, which when switched on has the SB going straight to the starter, and the HB to the alternator and thence onto to all House circuits. NO connection between them. This afternoon, I turned the switch to "Combine", which I hope is self explanatory ! Then I saw on the Link 20, some current going the SB, and CCCC also showing. The solar panel regulator was showing an input of 4.6 amps, with the Link 20 showing 3.8 going to to the SB and 0.7 amps going to the HB.

I guess the 4.6 amps all going to the HB and thence the combiner, wasn't enough to make the combiner split it. At any rate in future, I'll "Combine" the two batteries as I see fit.

Thanks for your interest.

[BrianGJS]

I had to track down a 3A continuous draw on my Cruisers 405. It appears to be a mechanical vs solid state relay issue connected to the smart stuff on the boat.

[hamburking]

Does the solar panel feed go through the smart meter?
Are the panels isolated when they aren't charging?

Perhaps one battery is charging the other, through your combiner, and you are seeing that current draw?

Maybe the smart meter is drawing 0.1 amps? Or some other "vampire" current draw, like a radio/stereo/tv/charger/cp which is switched to "off", but still draws some current?

And finally, I had a boat once where the compass light was always on...no way to shut it off. Maybe you have a light on, but can't see it in the daytime.

[MarkJ]

The monitor is showing a drop, but thats just a monitor. Are the batteries full? Check by voltage.

As your batteries get older do their Peukerts exponent (whatever) change a bit and you need to adjust its offset in the monitor? i.e. Change from 2.5 to 3?

Or are the batteries old and getting to the end of life?

[Russ]

Make sure all the wiring was connected to the proper side of the shunt. Don't ask me why I know and it originally was done by a pro when engine alternator was beefed up. Russ

[mitiempo]

Originally Posted by macbeth

I guess the 4.6 amps all going to the HB and thence the combiner, wasn't enough to make the combiner split it. At any rate in future, I'll "Combine" the two batteries as I see fit.

Combiners do not operate on current, but voltage. If your HB was down very far it would take a while for the voltage to rise enough for the combiner to close. This is especially true with the low output of a small solar panel. It would combine much quicker with a shore power charger or alternator.

[SeaSon]

The Link only measures the amps flowing through ground via the shunt - charge or discharge. It just counts up and down. It does NOT use the voltage to determine remaining battery capacity. IF the solar panel ground is not connected to the shunt it won't count those charge amps. Likely when connecting the batteries via the switch, solar ground gets connected to the shunt via battery connections or other loads.

My link doesn't count all the charge amps from my alternators for some reason, I assume the engine ground connections on the start batteries, so over time at anchor, it reads large negative numbers and will turn on the low battery indicator even though the batteries were fully charged that day. I just accept it, and look at the voltage only. Don't discharge below 12v - 11.9v with a load applied (12.2v, no load for 6 hours = 50pct discharge) so try to stay above 50pct, for long battery life. I use the Link amps indicator to monitor onboard loads. Mostly ignore the ah readings.

Regarding your mystery current draw, make sure voltage gauge on dash or panel can be switched off. They use slight power to indicate. Also your inverter will consume power in standby. Mine draws at least .5 amps @12v. I've seen 1.9a @12v being drawn with little to no load from the house. FYI, I recently had low voltage readout for the house bank, and replacing the inline fuse holder and fuse fixed that - the Link runs on and monitors the voltage from the same 12v line connected to the house bank, which is reported/sent to the Link via the telephone style cord.

[mitiempo]

The shunt for the monitor has to be the first connection after the negative post. There should not be any other connection to the negative post. If there is it will not get counted.

[domander]

I'm in agreement with others and suspect the panels are not sending their charge through the shunt. I did the same thing accidentally while wiring the power to my radar. The shunt informs the monitor about charge going in and out of the batteries. Anything bypassing the shunt, either power being used or power bring supplied, doesn't get recognized. Mitiempo is exactly correct.

- Brian Domander