New guy with electrical config question?

S

Stearmandriver2

New member
Hello all,

I recently closed the deal and brought home a very nice 2006 22 Cruiser... I'm the new caretaker of Notayot.

I'm just trying to understand my electrical system a little better. I have two batteries, and 3 selector switches: Start, House, and Emerg Parallel.

fNVekiZz_t.jpg

The House and Start switches seem self explanatory, but I'm curious about the Emerg Paralell and primarily, what the proper config is during normal ops. I'm pretty sure the seller said to run with all 3 switches on normally, but I question the word "emerg" on that switch; I'm used to only using things named that way in abnormal operations. I've also read cautions in the C Dory manual about tying the house and starting systems together, which it seems obvious to me that that's what this switch does (but I've certainly been wrong before).

I ran the boat for about an hour that way the other day (all three switches on) and everything seemed (still seems) fine, but I'm having second thoughts now. Can anyone with a similar 2 battery system chime in here?

Motors are a 2006 Honda 90 for a main, with a Tohatsu 9.9 aux.

Thanks!

Joe
 
Joe, you are right, the emergency parallel is usually keep the house bank separate from the start to keep it up to start the motor and on if your start battery is low and needs help from the house bank. But you need a way to charge your house so the parallel has to be on when motoring. BUT you have a "voltage sensing relay" in your system, if it is similar to a ACR that joins your two banks together when charging automatically then you only use the parallel switch for emergencies. I'm sure another C-brat will know exactly what that relay is.
Hope that helps.
 
Yes, he does have a voltage sensitive relay, so that the two batteries are combined when the voltage is over 13.6 volts (charging) and disconnected when the voltage drops to 12.7 volts. Thus run the electronics off the "house" battery, and then it is not charged until the start battery is up to 13.7 volts. Then they are "combined".

Use the combined manual (emergency): for just that, when the start battery is low, and you need to combine them to start the engine...

Congratulations on your boat!
 
When your running ( normal operation ) have the Start Bat switch ON, and have the House Bat switch ON, leave Emerg. switch OFF. Emerg. switch is only used if you come to your boat and for some reason you find a dead start battery. When your storing the boat, you would turn both of those switches to OFF.

Now here is a little problem, that BEP VSR may or may/not have the little red wire loop. The VSR is sensing the Start Bat, even when switches are in the OFF position. It is a very little draw. Newer models of that cluster have the little red wire loop, so it can be cut and a additional dash switch ( + ) / or it can be hooked to Ign. On (+) source. I have always wired to Ign. On (+) source. That way the VSR is working only when your main engine is running.

If you have a storage battery charger hooked to both batteries then no problem, don't just have a charger on the house battery.

Sorry if this is a little mind twisting.
 
san juanderer":3g1b9bw2 said:
When your running ( normal operation ) have the Start Bat switch ON, and have the House Bat switch ON, leave Emerg. switch OFF. Emerg. switch is only used if you come to your boat and for some reason you find a dead start battery. When your storing the boat, you would turn both of those switches to OFF.

Now here is a little problem, that BEP VSR may or may/not have the little red wire loop. The VSR is sensing the Start Bat, even when switches are in the OFF position. It is a very little draw. Newer models of that cluster have the little red wire loop, so it can be cut and a additional dash switch ( + ) / or it can be hooked to Ign. On (+) source. I have always wired to Ign. On (+) source. That way the VSR is working only when your main engine is running.

If you have a storage battery charger hooked to both batteries then no problem, don't just have a charger on the house battery.

Sorry if this is a little mind twisting.
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That is actually very helpful, thanks. I'm on the road now but I'll look for the red wire loop when I get home.

I'm glad you mentioned a battery charger because I forgot to ask. To clarify: if I hook a portable battery charger to the START battery, and turn on both start and house batteries, that will effectively charge both batteries (the relay will close and allow the house battery to charge once the start battery reaches 13.7v). Is that right? And actually, does either battery switch need to be turned on for this charging, or will that relay connect the house battery to the start battery (and charger) even with the switches off?

Thanks, sorry for the newb questions, I just couldn't find any documentation on this. I could just go out to the boat with a meter and answer most of this myself I guess... but I won't be home for three days and I'll bet you guys can answer faster. :lol:
 
Some portable chargers don't have a good 3 stage charge profile and long term float compared to the best of the built in marine chargers like the Pro Mariners. Long term with a portable may cook off more water if you have flooded batteries and may be even worse on gels and AGMs. The best maintainers might work out better in portable chargers.
 
Comes out the back of the VSR, you will have to dismount the cluster to see behind it ( literally a 2" loop of like 20 guage wire ).

House switch would have to be ON for charger current to reach house Bat.

Leaving the Bat switches ON, negates the whole purpose of isolating the batteries OFF during periods of storage.

Charger or chargers should be hooked directly to Battery posts. Some boats with very large House batteries may have 80 to 100 amp charger on that side, and a much smaller charger on the Start battery. So those switches would be OFF.
 
No problem with questions, that is the way all of us learn.

My impression is that the ACR (Voltage sensitive Relay is the same thing) is bi directional--that is if you are charing the house or the start battery it will combine when he voltage reaches about 13.7.
You can read a bit more on the Blue Seas Web site.

I'm glad you mentioned a battery charger because I forgot to ask. To clarify: if I hook a portable battery charger to the START battery, and turn on both start and house batteries, that will effectively charge both batteries
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Battery chargers:
Generally we discourage automotive type of portable battery chargers. They are not marine grade, and subject to rust, corrosion and failure. They are not as "safe" for the battery or the boat's electrical system. They are not always the "smartest" of chargers. There are several stages of battery charging: bulk absorption and float. You want a "smart charger". This will not over charge or damage the battery. Overcharging can damage batteries, as much as over discharging them. Basically never discharge more than 50% for longevity--and that means a "Stead State Resting voltage" of 12.2 volts. Never keep a battery on a charger which boils off the electrolytes.

I have several little 6 amp potted portable battery chargers; if I have a low battery, for example my fishing boat is an 18' catamaran, and no fixed battery charger. (Guest 2606A). My house bank charger is a NOCO Genius 30 amp 3 bank charger. There are a number of good marine battery chargers. You don't have to have a complete 110 V AC system, just a breaker or fuse on the input "hot" leg and a simple bass boat type of charger inlet, up under the gunnel, which will accept a heavy duty 15 amp extension cord. (MARINCO–15A Battery Charger Inlet)

Just running your outboard is not the best way of charging your battery. There should be a "top off" that last 15 to 20% of the battery capacity done with a shore side charger on a regular basis, for best battery life.

There are a number of chargers on the market. I tend to stay with Guest, ProMariner (Pro Series are more expensive, but worth it), NOCO has a 10 amp single battery charger for about $120, "smart"--samples the battery voltage and does a "test" before applying charge. Although I had not had any NOCO product before this boat, I have been impressed with their technology.
 
After an earlier discussion a while ago I double checked my Blue Seas ACR, it does maintain and charge my start from the house and charge the house from the start while of course isolating them when not being charged.

I started out last year with what I thought was a decent bass boat plug in charger as I only have a 220 AH house bank but the float stage boiled off water way too fast, I sold it and put in a Pro Mariner that senses a long term float and turns off till the voltage drops slightly, no more water boiled off. It is definitely worth twice the cost. I used to like my old Xantrex but now I really like the easy set up and charge style of the Pro Mariner.
 
Short term, for topping off before launching the boat or after using the house battery to power electronics etc while on boat in driveway, I guess a portable charger like this would be what's needed?
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It would work--but why not go with a few more dollars, and get one which is "built in". I have not checked out the circuits on that specific charger. I would not leave any clamp on charger on the battery for long term periods.
 
thataway":16a3jgj8 said:
Short term, for topping off before launching the boat or after using the house battery to power electronics etc while on boat in driveway, I guess a portable charger like this would be what's needed?
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It would work--but why not go with a few more dollars, and get one which is "built in". I have not checked out the circuits on that specific charger. I would not leave any clamp on charger on the battery for long term periods.
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Seems like solid advice. I've even got some Cabelas gift cards to burn, and they've got a ProMariner Gen3 Prosport 15 for $130. Think I'll go that route. Thanks again!
 
Follow up question: no downside to getting a triple output charger for use with two batteries, right? I could see maybe wanting to add a second house battery and it would be good to have an extra charging channel available if I do...
 
We have 2 group 31s for the house bank they are as is normal wired together in parallel so the 40 amp charger sees them as one battery your start battery will also be charged at the same time as your house through your VSR so you just need a big enough charger for what ever your future house bank will be, very simple. No extra channels.
 
Stearmandriver2":2jmaw7o6 said:
Follow up question: no downside to getting a triple output charger for use with two batteries, right? I could see maybe wanting to add a second house battery and it would be good to have an extra charging channel available if I do...
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The ProMariner chargers that have triple outputs automatically deal with two or three batteries connected without special wiring. On the Guest chargers that came with some boats, you have to wire the 2nd and 3rd outputs together if you only have two batteries (at least the one that was on my boat).
 
You may already know this, but be aware that multi-channel chargers usually divide their stated output among the channels. So for example, you want a 30 amp charger. If it has 3 channels, then only 10 amps will get delivered to any one channel. So if you only hook up one channel, your 30 amp charger just effectively became a 10 amp charger.

There are chargers (the more expensive) that will sense this situation and direct all the available charging power to whatever channel needs it, but you have to look for that feature.
 
I have the Xantrex Pro 40. It charges 3 bank at 40 amps each. It has been very adequate for my two Optima start batteries and the 4 6 volt golf cart batteries for the house.

Gene
 
Gene,

Perhaps your battery charger does do this, but I have never seen a consumer model that does. Every battery charger I've looked at can only deliver its rated charge (40 amps in your case) in total. When the manufacturers rate them at, say, 40 amps, they do not mean that each of the 3 outputs can deliver 40 amps simultaneously, but rather that the 3 outputs will share the total capacity of 40 amps. This limit is not often made clear in their documentation....for marketing reasons I presume.

Some chargers divide the total output equally across the outputs such that each output can only deliver a maximum of its share (for example, a 60 amp charger with 3 outputs, each can only deliver 20 amps max ever). Other units are smart enough to share the total amps dynamically (for example, a 60 amp charger with 3 outputs could deliver 60 amps to one output if there is no draw on the other 2 outputs).

Perhaps there is a charger advertised as a 40 amp charger with 3 outputs that can deliver 40 amps to each of the 3 outputs at once (i.e., a total of 120 amps), but I've never seen one in the typical consumer market.
 
Perhaps there is a charger advertised as a 40 amp charger with 3 outputs that can deliver 40 amps to each of the 3 outputs at once (i.e., a total of 120 amps), but I've never seen one in the typical consumer market.
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That would make it a 120 amp charger. I agree 100% with smckean.

An example of a "large charger" is the Victron 80 amp charger ( & inverter) I have on the 25. I have run the freezer and refrigerator for almost 24 hours, and the Li batteries were down about 60 amps. In about an hour that charger had gone from full output of 80 amps to float at about 2 amps, and it will taper every further. Most batteries will not tolerate this rapid a rate of charge.

Gene's 4 golf carts will handle 40 amps (I have put 100 amps into 4 GC, in an RV setting with a temperature probe on the batteries.). But the average group 24 (60 to 85 amp hours) might be damaged a 40 amp charge, Each type of battery has a maximum safe charging capacity. It is relatively low for flooded lead acid, and high for Li. AGM are in the middle. It also has some relevance to the max rate of discharge.

Page 1-2 of the Xantrex True Charge 40 (also for the 20) states:

The total current into the batteries is a maximum of either 20 amperes or 40 amperes, depending on the model, which is divided amongst the batteries according to their state of discharge.
Note: The three outputs are not independently voltage regulated so it is important to avoid systems with mixed types of batteries.
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Reading the manual, it didn't directly address if the full charge (40 amps) was available to only one battery, but I believe that it is. Some other high end chargers (MasterVolt, Victron, Blue Seas, and some of the Pro Mariner/Sterling series, as well as the NOCO) will allocate full charge to one battery if the charger senses the other batteries are nearly 100% charged. But one should have a temperature sensor, to limit the charge if the battery begins to overheat.
 
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