Dead Battery - ???

[tom&shan]

This Saturday when we got ready to leave the dock our battery was dead. We have the Optimax bluetop batteries, both house and starter. Both brand new this year (along with the boat). I turned on the parallel switch and then tried, the engine started. Then turned the parallel off and we went out for the weekend (alibet a bit more nervous than usual).
When we put the boat away two weeks ago, I alway turn both the house and starter battery off, so all three switches are off. This last time, the VSR light stayed on. Is the VSR switch possibly faulty? Why would the starter battery drain down so - is it possibly not charging? Any ideas.

i.e. Nothing was left on, all switches were off prior to trying to start the engine, new batteries.
Cheers,
Tom

[seahooked]

Tom,
I had a similar problem with my BEP 716 VSR unit (I believe the same model as yours- the one in the photo). For a long time I couldn't figure out why my house battery kept running down even though my loads weren't excessive. My start battery was always fine but my house would get down to the low 12's or high 11's (volts). Then I would have to manually recharge it. Finally I looked at it closely and found the VSR was never switching and charging the house; even with the VSR light working correctly. The best way to troubleshoot this problem is:
1- with the boat running normally and the start and house switches 'on', measure the voltage on the house battery.
2- now turn the parallel switch 'on' and measure the same voltage. It should be the same, around 14.5V in both cases. If it lower in the first case than the second, the VSR is not working right.
3- if the voltage is never getting up to 14+ in either case, you probably have a problem with outboard engine charge circuit. I don't remember if there if a fuse either in the outboard or between the outboard and the batteries; but probably one or the other.

Mine was reading around 12V in the first case and 14.5 in the second. I had EQ send me a replacement unit, swapped it out, and things were fine.

You definately want this problem solved before you do any permanent damage to your batteries.

[flapbreaker]

Make sure that the house and starter batteries are wired to the correct switch. Mine came from the dealer with them switched. Took a while to figure that one out.

If the light on the VSR was still on, I believe that's an indication that the batteries are still in paralel. Maybe it VSR is faulty or maybe it went bad do to incorrect connection to batteries/alternator?

[tom&shan]

I wonder if my problem with the starter battery going dead, and a possible bad battery switch have anything to do with excess static on the radio? About two weeks ago, for the entire weekend, the radio was almost consistantly blasting out static, turned the squelch all the way up and the volume all the way down, and could keep seeing the busy light coming on, so the static was steady - could barely make out the coast guard notices over the static .
Even this last weekend almost all transmissions are garbled with static - never having used a VHF I thought at first thats how they all work, but I'm beginning to wonder if thats normal. Calling into the Harbor Master outside the Marina we had to have him repeat himself in order to understand what was being said.

Tom

[thataway]

Static is not "normal" for a VHF (FM) radio. There is a squech, which can be turned down, to decrease static. You want to get the digital volt meter, and perhaps an analogue amp meter until you see how much current is being drawn. (Note the other post on the possiable drain due to CO detectors).

Depth sounders, GPS antennas, can be sources of static, as well as ignition noise. Some cables are not as well shielded as we might like. What other electronics do you have on the boat? Also an alternator can easily put out "hash"--electrical interference. You definately need to check the voltage of the batteries with the engine running.

Turn on and off variious appliances on the boat (including electroncis and engines) to see what the cause of the static is.

[edwardf]

If I may I'd like to add one small caveat to the discussion about batteries and voltmeters. It is a fine idea to have a modern digital voltmeter for troubleshooting but there is a gotcha with those. Testing batteries with them can lead you to false conclusions. A battery that wouldn't start your outboard can still read over 12 volts. It could be all but dead and still read 12 volts. The reason is in the theory. It has to do with what's called the input impedance of the voltmeter but suffice it to say the meter doesn't put any appreciable load on the battery. The good part with these meters is they usually give you enough significant digits that you can see 12.1, 12.65 etc. It looks like a little but it's telling you a lot.

[thataway]

To expand on Edward's post--to really find out the state of a battery one has to load test it. But for general trouble shooting, the volt meters which read to a hundredth of a volt are very good. I have guages on the consoles of both of my boats, with switches, so I can read the digital voltage of any battery at any time, without going to the volt meter. Most Fish finders and chart plotters will read the voltage at the unit--if there is a significant drop, then you need to start trouble shooting. I like to see 12.6 volts in flooded cells, 12.7 volts in an AGM battery when "charged at rest". The voltage from the alternators on outboards are generally in the 14 to 14.4 volt range (caution if you have gel cell batteries (not AGM), anything over 14.1 is too much). I have my VSR set to cut in at 13.7 volts and cut out at 12.8 volts.

Remember that a battery which reads 12.2 volts, at a resting state, is 50% discharged! When a battery drops below 11 volts, it's live span will be seriously affected.

[tom&shan]

[thataway]

To my knowlege the interference problem has not been an issue with the Standhorizon 350. I would look at the ignition system, or alternator. How do you have power comming to the radio chart plotter? I like to feed it off a house or electroncis battery rather than the engine start battery.

[tom&shan]

[thataway]

Tom,
The voltage sounds as if the alternator is putting out fine--If you have a 90 HP ETEC, I believe that you have a 75 amp alternator--large for that size!

If you can adjust the voltage cut out on the VSR, you might want to set it to 13 volts or 13.1 volts. It is keeping connected at 12.99volts. It is not unusual for batteries to keep a "surface" charge of over 12.6 or 12.7 volts. The AGM batteries have a slightly higher "resting voltage" than the flooded lead acid batteries do.

I think that something drained your batteries--Don't know what. I don't know what your VSR draws, mine runs 12 ma open and 175 ma closed (Blue seas 7600 Cl series ACR) or 4 amps a day--not a lot even if the realy had been stuck open! There are some items often wired directly to the battery--these include the Wallas stove (if you have one) the bilge pump--could have had a stuck switch and been on without your knowing it.

Check out any wires from the battery, if there is a fuse, you can put an ampmeter in the line right there, or pull the wire ane check the current draw.

[chromer]

Tom,

Ya started fishing with that downrigger last week - right? What battery were you on? I found that can really drain your battery fast - pulling up that 12lb weight. A quick run back to port, wont really be enough to fully charge. Every few weeks I hookup to my battery charger during fishing season.

[tom&shan]

[seahooked]

Tom,
Just some miscellaneous thoughts on what you're experiencing...

First, your making good progress in ruling out possible causes. I believe at this point you can say: 1) your engine alternator and its charging circuit are ok, 2) both batteries are probably ok, and 3) the VSR is switching properly and thus allowing the charging of both batteries. This said, there are still some puzzling things going on.

Off the top of my head I can visualize two possible senarios that could cause what your experiencing:

Senario #1: the start battery was never drawn down however the VSR Start Switch did not make good contact (intermittent flaky switch).
- in this case when you switched to 'parallel' the engine started on the house battery.
- the 'clacking' you described by the VSR unit is troubling. Clacking is typically a switch engaging and disengaging, and should never occur on a properly designed and functioning product. The VSR circuit in this case would be designed to switch a 13.7V however with a 'hysteresis' of a tenth of a volt or so to avoid continuous engaging/disengaging when the voltage is right at the 13.7V threshold setting. If the 'start' switch is not making good contact, it is possible it is causing the clacking.
- a flaky switch would be a perfect 'electrical noise generator' which could explain why your VHF radio is acting up.
FURTHER TROUBLESHOOTING
If the starting problem reoccurs, measure the voltage on the start battery (now that you have a good voltmeter). Assuming the battery is ok, try switching the 'start' switch back and forth several time and try again. If you can get it to work, the problem resides in the 'start' switch portion of the VSR unit.

Senario #2 : something is drawing down the start battery when all the switches are 'off'.
- my BEP 716 VSR documentation does not specify a current draw when all switches are 'off'. I suspect it doesn't draw anything in this case.
- you may have several accessories that are connected directly to the batteries. The only way to find out for sure is to see what you can activate with the switches 'off'. Personally I have the Wallas, winlass, downrigger, cockpit bilge pump, and shore power charger connect directly to the batteries through fuses on my boat.
- anything directly connected to the start battery could be a culprit. By the way make sure you downrigger stays unplugged when not in use (although you had this problem before the downrigger).
FURTHER TROUBLESHOOTING
Now that you have a nice 4 1/2 digit voltmeter, use the current measuring feature. Use the 10 Amp position first before the 400 mA because both are fused at their respective values. With everything 'off' remove the ground cable on the negative post on the start battery and insert the leads of the meter between the post and the cable. If you read zero amps, repeat with the smaller scale on the meter. If you see any current at all on either position, your looking at a problem. Start disconnecting any wires on the start battery one at a time until the current disappears. Be careful not to turn anything 'on' when you have the meter connected. It's easy to blow the internal fuses in the meter.

Good Luck!

[thataway]

The clatttering has been described before and is a known problem if the batteries/charging source are not matched. The voltage will swing enough to open and close the relay when the battery is too small. Since this is not currently happening and the battery and alternator seem to be in balance this is not a problem.