Another Battery Question... Help!

C

caution

New member
There was a lot of great information on batteries and electrical in some of the threads, which I'm still absorbing, but I have some specific questions and need to get straightened out in time for a trip to the San Juans the day after tomorrow.

We have a 2004 CD-25 that came from the factory with a refrigerator, Wallas stove, 2 batteries (one deep cycle for the house, one non-deep cycle for starting), and a VSR (voltage sensing relay). The VSR was installed by Sportcraft Marina down in Oregon. We have a Honda 150 main, plus a Yamaha 8hp (since the orginal Honda 15 was stolen.) The Yamaha is an electric start model that also charges the battery. Incidentally, I believe that the Guest battery charger on the 2004 model is actually the 3-stage variety, per its documentation.

The two motors are connected directly to the starting battery. The only other things connected to the starting battery are 2 Scotty electric downriggers, only because nothing else would fit onto the terminals of the house battery -- they are chock full of the other 12-volt connectors.

The VSR has 3 switches: Starting battery, House battery and Emergency parallel. I just leave all of these switches in the "On" position, figuring that both batteries will get charged and the VSR will handle that automatically. (But I don't know exactly how that device works, so maybe I'm not using it properly.)

We have been doing a lot of fishing lately, so we generally start out of Dagmar's in Everett, make a quick run to the Tulalip Bubble (45 minutes?), then troll for hours on end with all of our electronics running, with only the trolling motor running. We then go back to Dagmar's and plug back in to shore power for a week, which presumably charges both batteries. Two days ago, however, we started from Dagmar's, fished all day (8 hours or so), then ran on the main motor to Everett, parked the boat at the Everett Marina for the night and went home. We did not plug in to shore power, but we turned off everything electrical except for the refrigerator. When we came back the next morning, the motor would not start -- the battery was too weak.

So far this makes sense -- the refrigerator ran down an already low battery (duh). But doesn't the VSR protect against this? Also, when the motor wouldn't start, I of course plugged into shore power and turned on the battery charger. I then tried to start the motor almost immediately, and it still would not start. I then turned the "House" switch on the VSR to "off", and surprisingly, the motor started right up!

So...

Question #1: Could the charger have given enough of a charge to the battery, in (literally) the 2 extra minutes of charging? Or did switching off the House battery do the trick by taking the weak battery out of the circuit?

Questin #2: While we are trolling, I assume the small motor cannot charge nearly enough to keep up with the refrigerator, stove and electronics. But will the VSR prevent the starting battery from being drained in this situation? Do I have to turn the Start switch to Off, to prevent it from being drained?

Question #3: We have noticed lately that when we start the main motor, after having trolled for a few hours, some or all of our electronics (fish finder, radar, GPS and stereo) shut off and then come back on. They never used to do that, and we can't think of anything we've done differently -- it just seemed to start happening. Any idea why that would start happening?

Question #4: Does anyone know how a VSR works, i.e. what it actually does? I don't know the manufacturer so I haven't been able to find any info on the web. Should both batteries get charged if I just leave both switches on? (Whether I'm charging from the engine(s) or from shore power?)

Question #5: Is it completely insane to have the downriggers on the battery with the motors? I have a tough time believing they could draw enough current to be a problem, with the small Yamaha charging all the time, since we only retrieve the downriggers about 2 times per hour, per downrigger. (5 amps x 30 seconds per retrieval comes out to about .04 Amp Hours, by my math...)

Last question -- with all of our electronics, it seems like moving up to a larger house battery is a no brainer. Anyone disagree? Any other suggestions on how to improved this system, or even some thoughts on some better usage techniques? Should we switch off the Starting battery every time we turn off the main motor, so that the electronics never drain the starting battery? (Sorry, I know it's a lot of questions, but I need to start somewhere.)

Thanks all.

Tom and Sherry on the Caution Horse...
 
The biggest problem is that you are connecting the batteries all the time by having the emergency parellel switch on. It is there for an emergency, ie:when the start battery is dead. Leave it off, and the vsr will connect the batteries when the start battery is fully charged and allow the house battery to then charge. When the batteries, (now one bank) drop below a threshhold voltage level, the relay opens to isolate the start battery.

The second problem is the wiring configuration. There are many ways of doing it, but most of them are just not optimum. The whole point of the vsr/battery switch cluster, is to be able to isolate the batteries, or to selectively connect them. Wired like yours, you cannot connect your motors to a good house battery if your start battery is dead or shorted.

I feel that the wiring diagram that comes with your unit is not correct for most applications, as the emergency parellel connects the two batteries, not the two loads. This works, except in an situation when one battery is shot, and you need both the motors and the house loads to work. (Isn't that the point?)

This is the company that makes the switch, click on the wiring diagram to see how yours is probably wired. http://www.bepmarine.com/showproduct.cfm?productid=501
 
Second thing that jumps out is your comments about the electronics blipping off when you start the engine. That's a sign of a weak battery. The amp draw from the starter is drawing voltage so low that the electronics are affected. Assuming you are using lead acid batteries, if they have ever been fully discharged, they will never perform the same afterwards. Each time they get discharged the worse the problem gets. That would explain why it didn't used to happen but now it does.
Click to expand...

I totally agree there. In fact, everything may be wired correctly and you're only facing a global battery replacement and a new, more battery friendly useage procedure. In 30 years of travel trailer RV'ing I've learned that the typical RV'er only gets between 12 and 18 months out of so called "Marine deep cycle" batteries and useage between RV and boats is pretty similar. Long idle periods, occasional Senior Moment full discharges, heavy use at times, and more often unsophisticated chargers plugged in for days/weeks, rapidly take their toll.

The smart boater (and rv'er) usually switches to true deep discharge designed 6 volt golf cart batteries wired in series if they have room or they obsessively care for their stock batteries. Even then, feces occurs and battery life of the Golf Cart type is typically 4-5 years.

In a previous wifetime I served on diesel submarines where batteries are absolutely critical. The Navy takes incredible pains to extend the life of those batteries, maintaining them on a daily basis and checking them continuously. Us boaters and RV'ers just pay the price for lack of maintenance and learn to buy new batteries on a regular basis....

Don
 
1. Most likely taking the house battery out of the circuit helped.

2. You're right the trolling motor won't keep up with the load. The VSR will prevent the starting battery from discharging if you have the emergency swich off. By keeping this switch on the VSR is not accomplishing anything.

3. If you have the emergency switch off your starting battery won't affect the other electronics.

4.I don't know how it works, just what it accomplishes. Yes, keep the switches to both batteries on and both will be charged.

5. You probably won't drain the starting battery with the downriggers but the reason for the VSR and 2 batteries is to remove any chance of not having a good starting battery. With a manually startable kicker that charges you may be willing to take the risk, it's up to you.

Last Question. If you insist on using the fridge, yes you'll probably need a larger battery. If you don't use the fridge your kicker should provide most of the juice needed while trolling and the battery should be good.
 
All good suggestions! Just an FYI, I think the Yamaha T8 has a 10amp alternator so that is what you have to work with while running the kicker. That said it should provide plenty of power for your GPS/Sounder and downriggers.

I've run my Sounder and Scotty Electrics on my sled all day without draining the batteries enough to start the big V8. My kicker doesn't charge the batteries while running.

Were it me, I would probably install a second house battery. This will allow for multiple days of fridge use. I would also make sure to not turn on the emergency switch on the VSR UNLESS you have a dead starting battery.
 
There are a number of things going on here - perhaps only some of which can be communally solved. You might consider taking the boat to a trusted mechanic to ensure everything is OK now that you know how to shut off the emergency start feature on the VSR.

I can offer the following observations:

1. You should never connect all your electronics directly to the battery. If your house terminals are "chock full", you have a problem and whoever did the install for you should be shot. You need to run main power to a fuse block or circuit breaker panel (try a Blue Seas (http://www.bluesea.com)) using a heavy guage marine duplex wire and then wire each electronic/electrical component from there. In this way, you have fused protection for all electrical systems. A lack of fuses and gobbing leads to a battery is a great way to have a boat fire.

2. Your deep cycle should always be fully re-charged and periodically allowed to completely discharge. The fact that your system is charging two different battery types may prove problematic, especially because the VSR system, when properly configured will always be perferentially recharging the starting battery. Starting/cranking and deep cycle batteries also charge differently (probably why you were able to start off only the cranking batt when you connected the charger). I use 4 dual purpose (Interstate) deep cycle/cranking batteries for charging and house in by 22' (twin Suzis) - one for each engine, one for house and #4 currently a spare (pending a heater install).

Hope you get things sorted out!
 
Wow, you guys are awesome, as always!

Minnow, thanks for digging up the specs on the VSR, that was really important and helpful. And the problem of the electronics turning off when starting the main was due to me turning on the Emergency Parallel switch.

Also, Dan, I took your advice and added up the current draw for all of the devices, and it totals nearly 10 amps. Since it surpasses the 6 amp (max) of the Yammy 8, we'll need to plan an appropriate usage model and probably beef up the house battery. At least now we know what we're dealing with.

Thanks for the other comments as well, they are all helpful.

Take care, and we hope to meet more of you at future C-Brat events...
 
I use my boat frequently, sometimes a couple of times per week...so it doesn't sit idle for long. Today, I decided to test my batteries with my volt meter and found both reading only 11.9, about totally discharged. Both battery switches had be inadvertly left on, but all electronics are turned off and the boats on a trailer with the plug out....so the bilge pump should not have come on and drained them. It is factory rigged with Bep switches: one starting, one deep cycle; one starting switch, one house switch, one paralleling switch, and one bus breaker. I am powered by two 50hp Suzukis. Loads are light. Only electronics, no refigerator.

As the factory explained it to me, the switch setup, without turning them off, will automatically direct house power to the house battery, preventing draining of the starting battery. But I find that both batteries are equally discharged, and when charging, are charging at an equal rate. Looking at the Beb webpage, the arrangement I have is supposed to be for a single engine, not twins. Is this my problem? Did the factory goof?
 
Mike, 11.9 for a 12 volt battery is not that low. A 12 v battery in good condition will usually top off at around 12.6 to 12.8 volts and maintain it for a while. My understanding is the bilge pump will come on every couple of minutes, to test for water. Anyway that is what mine does, unless I shut it off manually. If the boat has set for a couple of weeks and the pump has been cycling, that could be why the batteries are down a little.
 
Sealife I have the same BEP switch setup on a Single engine (boat new in august). I recently had a problem that I didn't expect. Launched the boat and when I went to start the motor I got nothing. Not even an ignition light. I was and still am puzzled as to how there wasn't enough juice to start the main since the VSR (voltage sensitive relay) is supposed to isolate the two batteries to prevent this. Lucky for me I have a trolling motor wired to the house battery so I pull started it and let it run for a couple minutes. Then I tried the main and it worked. Needless to say I'm still confused about this BEP setup and just what the heck it's doing for me even after reading the details on their website.
 
Dave,

According to the post above mine and the tutorial, and what I have always understood in the past, 11.9 is discharged. My old boat never ran below 12.55, even after being idle for a couple of weeks. It only had a manual bilge pump. Now the automatic bilge pump....that might be something. When yours cycles on, can you hear it, or is it just an electronic test it does. I have never heard it cycle on, except when I wash down the cockpit and it gets enough water to activate it. I also have a pump in the little depression in the stern, and I believe that one is wired directly to the batteries, so perhaps when it was raining this past week, there was enough water flowing past and out the drain hole to make it cycle. I'll have to look into that.
 
Mike,

If it were my boat, I'd take the time to draw out a schematic, wire by wire, to see how they're hooked up and the voltage isolator hookups including symbol directions on each. It's possible there is a miswire, could happen.

Also, static battery voltage varies with ambient temperature, colder is lower. It's been colder than usual lately, perhaps...? Lastly, if wired incorrectly and the batteries are all in parallel, all it takes is one or more of them to be slightly different (all are inherently different), then one battery will try to charge the other which could fairly quickly drain both or all if they're not being charged or trickle charged during that period. Just some thoughts.

Steve
 
Mike-

Was the boat specifically set up for twins by the factory, or just produced as a generic boat w/o commitment to a single or twin engines? Who installed the engines, the factory or the dealer?

There is a problem that must be overcome with twin engine installations. If they are parallelled so that both engines are charging the same battery or batteries, the voltage regulators of each engine cannot accurately gauge the condition of the battery(s) it is trying to charge because of the voltage being applied by the other engine, which is trying to charge at the same time.

The usual solution to the above problem is to have each engine charge its own starting battery, and then make some provision for house power, either by using a third battery and/ or a battery combiner, battery isolator, or some such solution.

Do you have a diagram of the system set up in your boat by the factory? Is your set up exactly he same, or is it modified? Steve's suggestion that you draw out a diagram will be a great value in understanding your system and what could be wrong with it. Are there any "black box" electronic components that you can't see inside or don't know how they operate? These can complicate the development of an understanding of what's going on, of course.

You've had this boat rigged like this for a couple of years, right? If the system were rigged in a faulty or wrong manner, it should have given you trouble long before now.

When batteries get old, they begin to loose their ability to hold their charge. Usually one will fail before the other, even if they are the same age. Left in parallel, the weak one will draw the stronger one down to at least its own level., and if it's discharging internally, they'll go down together indefinitely. With the switch left in parallel for the first time for an extended period, it sounds like this is the probable cause.


The Rule automatic pumps have a timer in them that turns them on every two minutes or so to check for water in the bilge. If the electronic "brain" controlling the pump senses considerable current flow because the impeller is pushing water, it stays on until the load drops. If the load is light, meaning that the impeller is spinning in air, it shuts the pump off for another cycle. The regular automatic pumps have a cycle of about two minutes, and the Premium series will switch over to a 10 minute cycle after not finding any bilge water for a cycle or two. The drain from these pumps is virtually negligable unless there's water in the bilge.

You might charge the batteries with an external charger, and then, with each of them isolated, check their voltage over a week's period to see how their individual voltage drops and if they are equal in their performance. You might also test each one independently under moderate loads to see how they perform and if one seems weak.

Joe.
 
Just spoke with Scott Matherws at the factory. My boat is pretty new....August of 2005. The wiring is a factory deal. Both batteries, group 24, are crammed into the starboard lazerette with Bep switches and a Bus relay breaker for the electronics. The only way to remove the batteries, is to remove the cover frame for the lazerette. One of the batteries is so hard to get to, I can't even check it's water level. The way Scott explained the installation, each engine is tied to a seperate battery for starting, and that the electronics are tied only to the deep cycle battery. Supposedly, when the engines are on, both batteries get charged, but when the engines are off, the starting battery is isolated from the deep cycle battery which powers the house (electronics). The battery charger, and both bilge pumps, I think, are wired directly to the batteries.

Good advice, Steve, I either going to do it myself, or have someone map my system. When it stops raining here, (yes, sometimes it does rain in So. Cal) I'll have to go down to the boat and run the charger all day to bring them back up, then see if they stay that way. Question: with a multimeter, and everthing turned off, is there a way to see if a battery is leaking voltage?
 
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