12 V power drain when "all" is turned off

[jsbartley]

Friends, I've been struggling with diagnosing a power drain on my 1996 Beneteau Oceanis 400 batteries. Here are facts:

1. 3 large AGM (one year old) batteries on house bank and 1 lead acid battery for engine...these appear to be interconnected since putting a charger to one charges all. Recently did full check on batteries and they are all good, except engine battery which is borderline but above 12V.
2. Smart charger-inverter Xantrex Link 2000 with monitor.
3. boat is at dock, w/ no shore power, only 2x100W solar panels, with regulator connected to one of AGM batteries thru a Coleman 30Amp regulator.
4. Panel cables disconnected from regulator in show 20+ volts with good sun on panels. Coleman regulator shows over 5 amps coming into batteries.
5. But Xantrex shows -4amps, and batteries do not increase voltage above 12.3V, even with all electrical panel shut down.
6. I have disconnected CO monitors and bilge pump fuse, which I know bypass the panel. Not aware of any other devices that might be on.

Questions:

A. Does this mean I have a net 9A loss (5AMPS coming in thru solar panel regulator, resulting in minus 4A showing on Xantrex monitor)?

B. If so, what might be the cause of drain, and how should I go about finding it (or them)?

C. If not, why doesn't my battery bank charge up?

Is there a protocol or checklist to go through to diagnose this issue?

Thanks for any input!
Cap Steve.

[wingssail]

Originally Posted by jsbartley

Friends, I've been struggling with diagnosing a power drain on my 1996 Beneteau Oceanis 400 batteries. Here are facts:

1. 3 large AGM (one year old) batteries on house bank and 1 lead acid battery for engine...these appear to be interconnected since putting a charger to one charges all. Recently did full check on batteries and they are all good, except engine battery which is borderline but above 12V.
2. Smart charger-inverter Xantrex Link 2000 with monitor.
3. boat is at dock, w/ no shore power, only 2x100W solar panels, with regulator connected to one of AGM batteries thru a Coleman 30Amp regulator.
4. Panel cables disconnected from regulator in show 20+ volts with good sun on panels. Coleman regulator shows over 5 amps coming into batteries.
5. But Xantrex shows -4amps, and batteries do not increase voltage above 12.3V, even with all electrical panel shut down.
6. I have disconnected CO monitors and bilge pump fuse, which I know bypass the panel. Not aware of any other devices that might be on.

Questions:

A. Does this mean I have a net 9A loss (5AMPS coming in thru solar panel regulator, resulting in minus 4A showing on Xantrex monitor)?

B. If so, what might be the cause of drain, and how should I go about finding it (or them)?

C. If not, why doesn't my battery bank charge up?

Is there a protocol or checklist to go through to diagnose this issue?

Thanks for any input!
Cap Steve.

I think that without the shore power charger you will have a hard time getting full charge from the 2x100 solar panels, if you are only getting 5 amps.

Try these steps to get closer to the problem:

• Disconnect the engine start and check the voltage at the house batteries with a multimeter while solar is charging. If the batteries are not increasing towards 14v then maybe the solar is not enough.
• check each AGM seperately to ensure that one of them is not taking down the others, they should be equal after a few hours of charging and stay equal. (you'll need to disconnect them one by one.
• With everything turned off disconnect the plus cable from thebatteries and test the voltage between the disconnected wire and the post. If you see a voltage than it means something is drawing down the power.

I am thinking that charging your house batteries on a total of 5 amps is likely to be very slow if not impossible.

[thomm225]

Actually the 2 X 100 watt panels should be plenty to charge your batteries without shore power. (with all your systems off for a day or so)

I have about 155 watts of solar but only use my 65 watt panel when at the marina to keep my two 12 volt 90 ah batteries that are in parallel charged up to 13.6 volts

You probably need to disconnect the batteries from the load totally by removing the wires to the main switch.

You also may want to disconnect that borderline battery at least until you can get your other batteries to charge up to float

[GTom]

Any partial shading on the panels? Do they sit in a wrong angle? 5A/60W on a sunny day isn't much, though fully realistic if you are far from the ideal angle to the Sun.

[sailah]

Do you have an ACR connecting the house and start banks? I have a Blue Seas and even when I shut off switch I see -0.5A sometimes and I assume it's because the ACR is still seeing 12.8+ V from one of the banks (likely house with Solar) and connecting to start and amps are flowing from house to start.

[DaleM]

Assuming you don't have a drain or short to ground, it is likely one or more of the batteries have failed. Failed batteries can't hold a charge. The only way to test it is to disconnect and isolate each battery.
Dale

[barnakiel]

I would start with a simple fact that your Xantrek Link monitor may or may not be reading the solar input. The unit uses a remote shunt and for various reasons installers at times place solar input beyond the shunt (towards the batteries) and then you must disregards Link as an amp in out info. STILL, the Voltage info on Link 2000 is supposed to be correct.


So ... one thing to do is to look at where the solar input goes and make sure if Link shows the flow or (far more likely) NOT. Reset your Link 2000 just in case it went nuts (they do at times).



Next step is to make sure you are reading the 5 A from the solars aright. Is it what your solar regulator reads or is it what you have measured with your VOM instrument at the place where the solar cables join the boat system?


5A into almost any battery will, if slowly, fully charge the battery. This may take time, but it will happen.


Other points worth of note:


- an engine batt at 12V is considered DEAD in my book (normal level is about 12.75),
- if the start bat is linked to your house bank BAM and you have one potential culprit -


Because a dead start battery could (e.g. if joined on the 1/2/off/both switch) drain the house bank faster than the solar panels charge it.


I would test like this:


- make 100% sure the engine batt is NOT linked to house bank,
- fully charge the house bank from shore, leave for 24hrs, is it still at 12.75? FINE


- is it at 12.2 again (at least one batt in the bank is dead)



- now discharge the system to 12.5, apply the solar charger, leave 3 or 4 days,
- is the house bank at 12.75 now? FINE
- it is not? test the solar charger, cables, and whatever is between the panels and the batts.


Do have another look at that start battery area. It may be a dead start battery draining the house bank.


Report back in between sparks! ;-)


Good luck,
b.

[Cpt Pat]

Do you have a propane fume detector? If so, close the propane valve at the tank (for safety) and then disconnect the detector. See what happens.


Some detectors draw a surprising amount of current.


If that's not it, treat each wire connected directly to the battery positive terminal as a suspect. Disconnect them one at a time.

[Shrew]

Originally Posted by jsbartley

3 large AGM (one year old) batteries on house bank and 1 lead acid battery for engine...these appear to be interconnected since putting a charger to one charges all.

This would make it a single large bank, not 2 banks. Your banks aren't isolated.

If the batteries themselves aren't wired correctly, I'd be forced to assume nothing else is.

[Howler]

A couple other possible "stealth" battery drains:

AIS electronics are often connected direct to battery

If you have a car radio, sometimes they have a wire that goes direct to battery to remember programmed stations

[wingssail]

Originally Posted by Howler

A couple other possible "stealth" battery drains:

AIS electronics are often connected direct to battery

If you have a car radio, sometimes they have a wire that goes direct to battery to remember programmed stations

We frequently see in installation manuals, "connect directly to the positive terminal of the battery". Installers of equipment will also do that. Everyone, it seems, thinks that their item of electronica needs a direct connection, bypassing not only the switch panel but the battery monitor, ammeter, or whatever you might have to manage your system.

I, on the other hand, have only ONE wire on my house battery. It goes to the main battery switch, the output of which goes only to the switch panel in the nav station. Everything, EVERYTHING, goes though that switch, INCLUDING the alternator output and the starter supply which are on the house side of the switch. Other than those two, and the main Inverter and the Windlass (to keep the large amp loads off the meter system) everything goes through the battery monitor and is switched with individual breakers at the panel. The windless and the inverter have their own in-line breakers.

Yes, I have long cable runs and voltage drops. But I have big wires. At least when I switch the batteries to "OFF", its off. Everything, total (there is no isolator, bilge pump, anything).

The engine starts on whatever battery I have selected. The alternator charges whatever battery I have selected. There are no mysteries about how power is getting away somewhere.

Whenever I have friends who are trying to solve problems like the one the OP is dealing with here, I find a mishmash of connections and wires, with not single, definitive, pattern, and that makes it hard to solve.

[Cpt Pat]

Originally Posted by wingssail

We frequently see in installation manuals, "connect directly to the positive terminal of the battery". Installers of equipment will also do that. Everyone, it seems, thinks that their item of electronica needs a direct connection, bypassing not only the switch panel but the battery monitor, ammeter, or whatever you might have to manage your system.

I, on the other hand, have only ONE wire on my house battery. It goes to the main battery switch, the output of which goes only to the switch panel in the nav station. Everything, EVERYTHING, goes though that switch, INCLUDING the alternator output and the starter supply which are on the house side of the switch. Other than those two, and the main Inverter and the Windlass (to keep the large amp loads off the meter system) everything goes through the battery monitor and is switched with individual breakers at the panel. The windless and the inverter have their own in-line breakers.

Yes, I have long cable runs and voltage drops. But I have big wires. At least when I switch the batteries to "OFF", its off. Everything, total (there is no isolator, bilge pump, anything).

The engine starts on whatever battery I have selected. The alternator charges whatever battery I have selected. There are no mysteries about how power is getting away somewhere.

Whenever I have friends who are trying to solve problems like the one the OP is dealing with here, I find a mishmash of connections and wires, with not single, definitive, pattern, and that makes it hard to solve.

So do all your digital electronics reboot when you switch batteries, and your bilge pumps are de-powered with the master switch in the "off" position? Is your ammeter really on your positive lead, or is it a shunt on your negative lead (making direct connections to the positive battery terminal irrelevant)? I'm not sure that's not the behavior I'd want. To each his own! In the hopefully rare case you smell smoke, it doesn't take much longer to pull the lead off the battery monitor shunt - if the goal is to de-power everything. What's important is that all the direct connections to the positive battery pole are properly and individually fused.

[smac999]

unplug the solar. Does it change from -4a to -9 amp? Then You wiukd know. If you ha r the 9a draw

Yiu should be getting more the. 5a from 200w solar

[wingssail]

You're pretty much wrong on all counts Cpt

Originally Posted by Cpt Pat

So do all your digital electronics reboot when you switch batteries, No, the battery switch does not cut power when switching.
and your bilge pumps are de-powered with the master switch in the "off" position? Yes, they would be, but I can leave the master on and turn off every other circuit except the bilge pump
Is your ammeter really on your positive lead, or is it a shunt on your negative lead (making direct connections to the positive battery terminal irrelevant)?I have three ammeters: engine alt output, house usage, solar output. Each ammeter has it's own shunt (or internal shunt) and is wired between the house post of the battery switch and the component being measured. Other devices, such as the Inverter/Charger have their own displays, however the windlass, while having it's own breaker, has no display, nor does the starter or alternator. So yes, the starter and alternator are unprotected.

I'm not sure that's not the behavior I'd want. To each his own! In the hopefully rare case you smell smoke, it doesn't take much longer to pull the lead off the battery monitor shuntIt would take infinitely longer to expose the shunt and pull off the lead (bolt) than to reach up and rotate the switch, however the only items not protected are the starter and alternator. I'll accept that risk - if the goal is to de-power everything. What's important is that all the direct connections to the positive battery pole are properly and individually fused.Absolutely, and in the case of my set up, they are (starter and alternator have no fuzes), there are 21 breakers on my panel. In the case of multiple items on a single breaker, each has a fuse in it's power lead

Cpt Pat, my set up is elegantly simple and consistent, safe and manageable. My wife Judy, or anyone who takes a 5 second look at our system can see instantly what is going on and see what to do. Further I have wiring diagrams and labeling on everything. And I did it myself, 30 years ago. OK, for absolute safety I could add a high amperage breaker on the positive lead between the battery and the switch, I'm not sure how valuable that would be if it was high enough to allow alternator and starter to pull their required power without breaking.

Compare that to the OP's, or anyone's situation with an octopus of wires on the battery's positive terminal and they really have no idea what is going on (as proven by the length of this thread).

[sailorchic34]

Several thoughts.

When connecting or reconnecting solar to a charge controller. Be sure that the charge controller is connected to the batteries first, then reconnect the solar panels to the charge controller.

Why.

Many charge controller use the voltage it see's at startup to decide if its a 12v system or a 24v system. if you connect the panels first and battery second then your charge controller will see the 20v solar output and assume you have a 24v system. That can cook the batteries.

The other thing that may happen is the solar charge controller will think it's a 24v system, with seeing 20v and with 12V will assume the batteries are dead and not charge the batteries.

I know of someone that did the above (hooked up solar first, and it either cooked the batteries or would not charge, thinking the batteries were flat.

Second thought. Disconnect alternator hot wire and see if voltage climbs. Could be a bad diode on the alternator(s).

Lastly disconnect the start battery with it's 12v (it's dead jim) and see if the house batteries come up. A bad cell can bring the whole system down.