Battery Setup - 1998 405 Aft Cabin

[Mikwallace]

Background - Purchased the '98 405 AC in Aug '22. Brought it home from Knoxville, TN to Lake Guntersville, AL; nice 4 day trip no problems. We took an extended vacation (without boat) and I'm just now back home to start going through the boat and figuring out what's what. I'll start with the batteries. First of all, there's no issues starting either engine or generator. I'm just trying to figure out what's been done and what batteries run through which Battery Selector switch, and which batteries run the house, port engine, std engine, and generator. Another thing I was looking at is how to connect an inverter to run minimum stuff. While looking through all the manuals in the Carver briefcase, I found a Power Inverter Owners Manual (Original Equipment- Heart Interface Model HF600-12). I figured maybe the boat came with an inverter but perhaps it was removed?? Then I started looking through compartments just familiarizing where stuff is located. Low and behold under the dinette seat I found a milk crate with 3 qts Castrol HD30 engine oil, 1 gal antifreeze, transmission fluid, and a couple funnels' AND two black boxes with wires. One of the black boxes is the aforementioned 600w inverter and the other black box is an auto transfer switch. It appears the inverter only powers the stereo system and salon TV (possibly the main stateroom TV, too. just didn't think to look at it?)

Now to the batteries! All the batteries look new and in good condition; I guess they were just bought at different times and different places. Two batteries are Rural King, Two are Autocraft, and the other is a DieHard.
Batteries 1 (675cca), 2 (750cca), 3 (750cca), & 4 (750cca) are ALL Deep Cycle Batteries. Battery 5 is a Cranking Battery (1000 mca).

Battery 3 is the Generator Cranking battery and wired through an ON/OFF switch. It's pretty straight forward.

Battery 2 is apparently the Port Engine cranking battery. I came to this conclusion because the Black/Ground wire goes to the Port Engine. The POS Red cable goes back through a bundle to the 1/2/BOTH/OFF switch.

Battery 1 is apparently the Starboard Engine cranking battery. I came to this conclusion because the Black/Ground wire goes to the Starboard Engine. The POS Red cable goes back through a bundle to the 1/2/BOTH/OFF switch. But Battery 1 is also Parallel wired to Battery 4, and Battery 4 is Parallel wired to Battery 5.

All 5 batteries are wired to the Battery Chargers. The battery chargers are new equipment installed prior to my purchase. They are Xantrex TrueCharge 2 chargers that can charge 3 batteries each.

For whatever reason, the Inverter is not connected to the batteries. The Red (positive cable to the Inverter) cable is just lying in the bilge next to Battery 1, as if it used to be connected to Battery 1. This red battery cable was a writeup on the Survey, so I just electrical taped the cable-end for the journey home and wire tied it off so not to vibrate against anything. Although now I know what the red cable goes to; therefore, it was not a hazard.

SO??? Where do I go from here??? It's organized but the wiring diagram looks unnatural!! Does anyone have a factory service manual with the wiring diagram???

I'm not real sure where the Positive cable comes from that goes to the DC distribution panel?? It comes out of the bundle that goes to the 1/2/BOTH/OFF switch. I'll have to take the DC panel cover off and trace that wire.
Battery 1 is paralleled with three batteries and I think goes to the 1/2/BOTH/OFF switch. Battery 2 goes to the 1/2/BOTH/OFF switch. The switch is set on BOTH. Which means that when I start the engines they're getting power from 4 batteries! The house power is, I guess, coming from Batteries 1, 4, & 5. But if the house is getting power from 1, 4, & 5 that could pull the batteries down if running interior lights, refer, and 12v stereo at helm? Then throw the Inverter in, if connected to Battery 1, running TV and 110v stereo in the salon. It just doesn't look correct!!

The Carver Operation and Maintenance Manual says to start the engines using the high voltage battery by using the selector switch and after starting both engines select the low voltage battery "to permit the engine alternator's voltage regulator to sense the charge level of an individual battery." But if Battery 1 has three batteries in parallel??

Am I missing something?? Shouldn't the house batteries be separate so not to pull the cranking batteries down while at anchor? I'd like to re-connect the Inverter, do I wire it to Battery 1 where the cable will reach?

Any information from you guys would be appreciated!!


Attached is a JPG file that I drew trying to figure out what's been done.

Battery Diagram.jpg

[KyleR]

I have ran into similar issues. It seems people want to try to get as much "redundancy" as possible by cross-connecting everything!

Have you been able to find a "house" disconnect (i.e. ON/OFF switch)? There should be one somewhere. You didn't mention where the RED POS cable from the house batteries was going but if you follow that it should lead you to the house battery disconnect. From there would be the typical path to the DC distribution panel. It seems very odd that they would wire the house batteries into the 1/2/BOTH/OFF switch, but again, people do weird things. If you can find that disconnect it might shed some light.

I'm not real sure where the Positive cable comes from that goes to the DC distribution panel?? It comes out of the bundle that goes to the 1/2/BOTH/OFF switch. I'll have to take the DC panel cover off and trace that wire.

One thing I've learned is that when a lot of the same color wires (e.g. red) all run into a bundle, my eyes sometimes play tricks on me about which one is going where. I now just cut all the zip-ties and remove covers to ensure what I think I see is accurate. It's much easier to re-tie everything back than wasting potential hours thinking the wires are running one way only to find out they're not. Been there - done that!

Good luck!!

[bud37]

Have a good look at the red cable ends at or near the batteries, they were labled and the numbers may be still there, with one referring to one on the switch, etc. In the manual you may find a diagram which shows the 1,2.all off switch and what load is connected to each terminal....for example house loads may be 1, 2 could have bilge pumps/ windlass etc etc. with some loads wired directly. You can start either engine from #1 , #2 or both, that switch may also control how the batteries are charged from the engines, watch your volt gauges on the dash as the switch is in different positions.
As for the grounds to the engines, that does not definitely mean that battery is for that engine......there is a main ground connection point on each engine and there should be a separate ground cable joining both engines together at those points.

Thats enough for now, have a look around some more. You can check wire runs continuity with a multi meter. Hopefully some of this applies to your particular boat model and helps......good luck.

[km1125]

From what you wrote, I suspect you have just two battery banks. Bank one (made up of three actual batteries 1, 4, 5) is wired to the "1" position on the switch, and battery bank 2 (made up of just battery #2) is wired to the "2" position on the switch. There is no "all" connection on the switch, just a COMMON connection, and I suspect that both your engines and your house lead is connected there. You can test this. When the switch is OFF, does ANYTHING work? Can you crank either engine or use any of the 'house' loads? Then switch to position "1" on the switch. Can you crank either engine or use any 'house' loads? Then go to position 2 on the switch and do the test again.

If EVERYTHING works on either position 1 or 2 is selected, but NOTHING works when "off" is selected, then what I suspect is true.

You can make several changes to the system depending on what you really want to accomplish, but I would recommend at the minimum to get and install a VSR (voltage sensing relay) and put it between banks #1 and #2, so that you never have to run on "both" to charge the other batteries... the VSR would do that automatically for you.

[g36]

I have a 405 . The oem inverter only ran the stereo system stbd side by the steps in the cubby. No tvs. Under the steps youve found the battery selector switch and breakers for windlass and sump pumps. I can forward you the carver 405 oem manual. It does have the wiring and other systems. Shame if your boat didnt come with this.Theres really no change between 405/406 in this regard. If you'll send me a private message I'll send it your email. I use 6v golf cart batteries for my house bank and have used this for many many years and has worked well for me. I leave the battery selector alone it stay on bank 1 isolating from the other bank. If I ever need it it will be switched to bank 2 to get me going. I would suggest getting a better and sine wave inverter . The oem 600 watt is rather pathetic and very limited on its use.

[Mikwallace]

Thanks everybody!! I’ll continue to research and chase sparks until I get this figured out. I do have the OEM Owners Manual and will read through it again.

[Viper]

Source of the post...I would suggest getting a better and sine wave inverter....

+1. The cheaper "modified sine wave" units have too dirty a waveform IMO which affects most power supplies, inductive loads, etc. The accessories/appliances will work but not as efficiently and you'll shorten their life expectancy. Newer inverters are also more efficient than their older counterparts.

[Mikwallace]

Source of the post From what you wrote, I suspect .............................................................. then what I suspect is true.

You can make several changes to the system depending on what you really want to accomplish, but I would recommend at the minimum to get and install a VSR (voltage sensing relay) and put it between banks #1 and #2, so that you never have to run on "both" to charge the other batteries... the VSR would do that automatically for you.

I'll try this when I get back to the boat next week and post my results.

thanks!!

[Phrancus]

Simple rule: all negatives are together on a boat. It's the positives that are separated into groups.

A single battery is the same as multiple batteries connected together in parallel.

I noticed that you write something like 'after starting the engines switch...' If you disconnect a battery from a running engine, you toast the alternator is what I read regularly. And switching usually means a point between the one and the other that is not a connection. Be aware that this may be a potential risk.

When working with battery poles, take the usual precautions when reconnecting. Those things are often made of soft metal, tightened too often and too tight so it's not uncommon that you can't put it back the way it should. Replace when you can't get them bright clean or the nut wont 'grab' the thread any more. Clean the clamps from rust, the battery posts form oxidation and after mounting grease it in to prevent new oxidation forming. Sounds obvious but everyone spent time figuring out the cables, disconnecting to follow them all over and then running out of time and energy so quickly put them back, (over)tighten the nut without feeling it grab. And a week later it won't start due to a loose connection on that battery terminal. (been there, done that and the latter happened during the pick up after the sale....man, I felt stupid.)

[Mikwallace]

Source of the post I have a 405 . The oem inverter only ran the stereo system stbd side by the steps in the cubby. No tvs. Under the steps youve found the battery selector switch and breakers for windlass and sump pumps. I can forward you the carver 405 oem manual. It does have the wiring and other systems. Shame if your boat didnt come with this.Theres really no change between 405/406 in this regard. If you'll send me a private message I'll send it your email. I use 6v golf cart batteries for my house bank and have used this for many many years and has worked well for me. I leave the battery selector alone it stay on bank 1 isolating from the other bank. If I ever need it it will be switched to bank 2 to get me going. I would suggest getting a better and sine wave inverter . The oem 600 watt is rather pathetic and very limited on its use.

How did you connect your 6v golf cart batteries? Did you modify the OEM setup connection? Do they go thru the 1/2/BOTH/OFF switch, direct to the DC breaker panel, or did you install another cutoff (ON/OFF) switch?

Does the 1/2/BOTH/OFF switch also have an Isolator built in? The Owners Manual indicates that when the switch is set to 1 then the Battery 2 will not charge? (If I read it correctly?)