Free T-shirt or hat if you solve my problem

[Chris Reinke - CD330]

I am looking for some assistance in solving my electrical problem and will offer either a CD hat or T-shirt (Leo and Catherine please advise T-shirt availability) to the sailor who provides me with the corrective solution. I have re-posted my previous message below, plus my follow-up findings from last nights endeavor.

6/12/00 posting:
I am totally perplexed. Like most sailors, I consider myself to be relatively proficient in trouble shooting the onboard systems – but this has me totally confused.
At the end of last season my batteries and charging system were functioning perfectly. I have two group 27 batteries (purchased 8/99) hooked up as my house bank and an automobile type battery (purchased 4/99) as my engine bank. I replaced my alternator at the start of last season with a high output model. I have a dual bank Newmar model ABC 12-15 charger wired directly to each bank.

Here are the three confusing issues which may or may not be related:

1 – The shore power indicator light comes on when the shore power is connected. The indicator light begins to blink randomly and dimly when I turn on the battery charger. I can operate appliances in the outlets without any problem and the indicator light remains on providing the charger is off.

2 – The battery charger has an amp meter located on the front panel. The charger shows it is putting out almost 15amps when it is turned on. After about 5 minutes of operation the charger will suddenly drop to 0 output at which time the shore power indicator light will return to full intensity and no longer blink. After another 3 to 5 minutes the charger will kick back on and the shore power indicator will begin the blink dimly again.

3 – While out sailing this past weekend I was motoring down the Hudson River during the early morning hours. The amp meter on my engine panel indicated a moderate charge when I first started the motor. After 15 minutes or so the amp meter showed little output so I assumed my batteries were fully charged. Once the wind picked up an hour or so later we raised the sails. I had only the cockpit instruments operating off my house battery bank of two group 27 wet cells. After 3 hours of sailing I tried to start the motor while using the house bank. The battery level had dropped from 12v to 9v and was unable to turn over the motor. I was able to start the motor without a problem off my other battery bank.

Any ideas as to why my battery charger would cause my shore power indicator light to blink dimly? Any ideas as to why my charger would peak at 15amp output and then suddenly drop to 0? Any thought as to how my minimal cockpit gauges could draw down 2 group 27 cells after only several hours (last season I could get 24 hours of gauge operation without the need to recharge the cells)? Can all these items be related?

I guess my last call for assistance should be to ask if anyone knows a good marine electrician in the New York area?

Any thoughts or comments would be appreciated. I am at a total loss to explain this one.


6/15/00 Posting:
Last night I went down to my boat with the print outs of the various suggestions I received in one hand, and a digital multi-meter in the other. I was committed to isolating the cause of my electrical drain / short and fixing the problem.

Now for the frustrating part – Everything was operating perfectly when I arrived at the boat. Both battery banks were fully charged at 13.25v, the charger was cool to the touch and the amp meter indicated only a minimal trickle maintenance charge. The refrigeration had been left operating the charger had functioned sufficiently to maintain the battery charge level and power the refrigeration when needed. The only problem I found was that the shore power indicator light (the little red one) on my electrical panel continued to flicker intermittently, and would go off completely when I turned on the shore power breaker. I determined the shore connection was adequate by monitoring a constant supply at my onboard outlets.

I isolated each battery and monitored the depletion rate over a 30 minute period for each one (this gave me 1
hours to tinker about the boat – something we all do so well). I had each battery power my instrument, radar, GPS, and refrigeration. Each battery (both group 27 and my automobile starter battery) rapidly dropped from their initial charge of approximately 13.25v down to 12.25 within the first 5 minutes. Each battery then dropped at a reduced rate until they leveled out at approximately 12.05v to 12.10v towards the end of the 30 minute period. I then started the engine and noted my alternator output was 13.85v and returned the batteries to a full charge level within 5 minutes.

So now what? I am scheduled to leave in 3 days for a 10 day cruise from New York along the New England coast and am concerned that the problem will return. Any suggestions? I am already planning on pulling the battery out of my car when I arrive at the marina so I can take it with me as extra security. Is it possible that the 90 degree weather we experienced last weekend was sufficient to cause the charger overheat breaker to trip? Is this a problem in warmer climates that I have just never heard of?

Any thought or suggestions would be appreciated.

Chris Reinke



chris.reinke@transamerica.com

[D. Stump, Hanalei]

Chris,
3 things: 1. There is nothing wrong with your batteries - the start voltages are normally above 13 volts right after taking them off of the charger or alternator. The leveled out voltages are OK too, at least what I would expect. 2. The alternator is probably OK too, charge voltage sounds about right. 3. The charger - now here may be the problem. An intermittent output ground would be one guess. The fact that it showed 15 amps out and then shut down shows an overheated output coil and there is a thermal overload protector built into the charger. It trips, and when the coil cools off, it resets.

OK, that's what I see from your explanation, but the question is what pulled down your two house batteries? It could be the output ground on the charger, but it would be a massive current draw to do it so quickly. I would think that something would get HOT! Now my question, Did you change out anything else electrical in the time before you noticed the problem? How about a glow plug switch? If you did, and wired the glow plug switch in wrong, the plugs will be energized at all times while the ignition is on, and that will draw down your batteries RIGHT NOW!

Finally, I have no idea why the shore power light is flickering, it may be an entirely seperate problem.

Dave Stump
Captain Commanding
s/v Hanalei CD-30

[Ed Haley]

First let me make an assumption regarding your situation. You have three batteries, two house batteries that are connected together to supply your needs aboard the boat and an isolated single starting battery. This is a relatively common arrangement for higher current draw when operating electronic navigation and other equipment. When two batteries are connected together for simultaneous discharge, there is usually another discharge that may be present in your situation.

One of the two connected batteries is usually at a slightly lower potential than the other due to age or condition. It appears to the other higher potential battery that it is in need of a charge. The higher potential then begins to charge the lower potential with an impossible task. It can never bring it up to the higher potential. Soon, both batteries are spiralling down, one trying to charge the other, until both are discharged.

Batteries can be connected for charging purposes but should be isolated for discharging for this reason.

Hope you find the problem.



eghaley@twcny.rr.com

[Matt Cawthorne]

Chris,
Firstly do not burn your boat to the waterline! If you suspect the wiring or battery charger are in any way malfunctioning then do not leave the boat plugged in.
Firstly, I would recommend an additional check on the batteries. 12.1 volts after 1/2 hour might be right if your frige was running continuously, but it sounds like it is a little too low to me. Check the specific gravity of the electrolyte in each cell. They should not have gone bad yet and the fact that they are behaving the same would leave one to conclude that they are ok.
What data do you have to indicate that your batteries are fully charged after only 5 minutes? If you have a multi-stage regulator on your high output alternator (the most common thing to do) then the charge voltage should go to something like 14.2 volts after a period of time and drop back down after the Bulk and absorbtion charge cycles are complete.
Measure the voltage at the indicator light when the charger is switched on. The problem could be that the voltage is dropping on the positive side or, more disturbingly, it could be increasing on the negative side. Compare them to each other and then compare them to an independant ground. Even a 20 amp charger should only be drawing 2 amps of 110 volt current so should not affect the house voltage in any way. If it is, return it for service.
Taking the car battery is a smart idea. If your batteries get flattened again disconnect the newmar charger from both the DC side and the AC side and charge your batteries with the alternator alone for a while. Bring lots of ice so that you do not need to run the frige in the event that your problems continue.

One of the best investiments that I have made for my 36 is a battery monitor. It is a great tool that I use regularly. Just after I installed it the original alternator went bad. It would charge the batteries slowly, but would also draw 3-4 amps out of the batteries when the engine was off. I was aware of the problem within an hour by checking the monitor. I was able to disconnect items one-by-one and sort out the cause within an hour of starting work on it. On occasion I have left the engine compartment light on. It is easy to find things like that just by monitoring the current draw. The down side is that the battery monitor is expensive.

Matt



mcawthor@bellatlantic.net

[Ken Coit]

Chris,

Are your paralleled batteries wired such that the bus from the positive side towards the selector switch is from one battery while the bus from the negative side to the common ground point is from the other battery? If they are, the cable resistances will be similar for both batteries and they will tend to drain equally. If not, then you may be experiencing the spiralling down that was described earlier. Another thing to look for is a poor connection at one of the batteries as this would have the same affect.


Good luck,


Ken Coit



parfait@nc.rr.com

[John Sill]

If it's one problem, seems like a bad ground or a "short" between the AC and DC systems to me. I agree that the charger is overheating and cycling. However ... what is it "charging"; maybe not the batteries.



jesill@erols.com

[Murray Glue]

Chris,

I am a marine systems engineer. One possibility is that your battery charger has a fault in it which may be a bad connection internally or externally and causes the voltage at the input to go low when the charger is under load.

You need to get the charger secondary ( output ) isolated and connect it to a seperate battery sitting in the cockpit. If it charges this correctly then the fault is external to the charger.

External causes will be harder to find. You need to borrow or buy a clamp meter which can read DC current, learn to use it , and go looking for the drain. But first fix the charging problem.

I have a CD30 which I like a great deal, but I would like to keel haul the idiot who wired it up.
My first act on buying the boat was to rip out the panel, dual batteries charging system and most of the electrics and go back to basics. With a bit of kiwi ingenuity I got 24 fused circuits on the electrical panel, and went to a single 240AH battery source for all purposes. I do need to keep a careful eye on the battery state, but the single bank gets rid of splitting diodes and all sorts of complication.

What I do is keep a second set of the Trojan six volt cells which make up the battery bank, at home. The spare set is cycled and charged regularly, and changed out with the set on the boat every three months or so.

Good luck with finding the problem.

Murray Glue



106452.2173@compuserve.com

[John R.]

Chris,
3 things: 1. There is nothing wrong with your batteries - the start voltages are normally above 13 volts right after taking them off of the charger or alternator. The leveled out voltages are OK too, at least what I would expect. 2. The alternator is probably OK too, charge voltage sounds about right. 3. The charger - now here may be the problem. An intermittent output ground would be one guess. The fact that it showed 15 amps out and then shut down shows an overheated output coil and there is a thermal overload protector built into the charger. It trips, and when the coil cools off, it resets.

OK, that's what I see from your explanation, but the question is what pulled down your two house batteries? It could be the output ground on the charger, but it would be a massive current draw to do it so quickly. I would think that something would get HOT! Now my question, Did you change out anything else electrical in the time before you noticed the problem? How about a glow plug switch? If you did, and wired the glow plug switch in wrong, the plugs will be energized at all times while the ignition is on, and that will draw down your batteries RIGHT NOW!

Finally, I have no idea why the shore power light is flickering, it may be an entirely seperate problem.

Dave Stump
Captain Commanding
s/v Hanalei CD-30

I voiced in on Chris' problem with his previous post and highly suspect an internal charger board malfunction and recommended he return the charger to Newmar for bench analysis or at least call their service department for a consult. Apparently he has not contacted them to date. But for the flickering AC light I believe those are neon bulbs and they will start flickering when they age and eventually fail. The light flicker Chris is experiencing may be related or unrelated as you state. My AC light has been flickering for about ten months and I know it is a slow internal bulb failure as there are no other manifestations of electrical problems on board.