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Need Help with Battery Setup

rmm

Regular Contributor
So this is my current battery setup on 1988 31' Tiara. I have a problem where I can't turn my electronics on until after the Starboartd motor is running otherwise the surge restarts all the electronics. Thinking I can resolve by seprating out the House side OR is there any easier way?

I was planning on:

1)Rewiring the Starboard motor to the Port switch (will I need to replace with a 1/2/both/off switch?) or can just connect to existing?

2) How do I still keep the alternator charging the Starboard side House battery?

3) Anyone know what the box with the orange wires is above the parallel switch?
 

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Your situation is not all that unique or unusual. Starter Motors can consume heavy amp loads, reducing voltage, as is the case with your electronics. The electronics shut down to protect themselves.
Most twin engine boats, in this size range, supply house loads via the Stdb side engine battery bank. I hate to see you take your House Bank completely out of the loop (isolating it from Stdb engine), but it would resolve your issue, as long as you brought engine alternator charging abililty back into the system..... of which is pretty easy to do!
You would then crank your Stdb engine from your "shared" Port side cranking bank. This too is not all that uncommon!


I'll also suggest that the HTGR/PMGR starter motors require slightly less amps to crank the same engine. These will also usually kick butt over the Non-GR OEM starter motors (if that's what you now have).
IOW, if it's time for a starter motor replacement..... this would be the route to go.... IMO.
These generally cost less as well.

You may want to look at some of the Bluesea products. Bluesea offers some auto-combining switches that may be better suited to solve this issue for you.

If you do separate the House Bank out, consider an ACR (auto charge relay) or VSR (volt sensing relay) that could become integral with your charging system. This would solve your engine alternator charge issue.


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BTW, both alternators can charge the House Bank when these are used. There are no inherent issues or conflicts when doing so.


I see that you're using two 6v Golf Cart batteries in series (a group of 2) increasing your Amp Hour capacity...... wise move! :D Have you considered adding 2 more? (4 of them?)

I crank my Stdb engine on my large 6v house bank.
While we should NOT crank on Deep Cycle batteries, there are No issues if the bank is large enough! However, I am using the HTGR/PMGR starters. Makes a slight difference, IMO.
Just a thought on that!


The mystery solenoid (with the orange leads) may be an older ACR, or a version of an ACR, that has been added. Hard to tell without more info/detail.



BTW, you could achieve the same "manual combining" by eliminating your ON/OFF switches, and installing two (2) MBSS's (main battery selector switch) also eliminating your one on/off manual combining switch.
You'd have a total of two (2) MBSS's only!
Your "manual" combing would now be achieved via the BOTH/ALL feature of each MBSS. (i.e., both switched to ALL). However, this requires that we remember to return them from this position!

Bluesea also provides excellent switching components that provide this capability. However, I prefer the KIS/ALC...... keep it simple and less costly.... and via parts that are easily available.

One more thought that is simple, yet effective.... is a helm switch activated continuous duty solenoid that momentarily combines Port/Stbd banks for heavy cranking loads! (this may also be your mystery device)
I've done this on my own twin engine boat..... it's my poor man's version of an auto-combining feature.
With a flick of a momentary on/off helm switch at the helm....., the continuous duty solenoid momentarily combines both battery banks (via the "common" terminals) during starting.
I can reserve this feature for a low battery bank scenario....... or to prevent electronics from shutting down.
Either way..... it is simple and works very well.

There is a Bluesea product that does essentially the same thing, but is tied in with your starter motor circuit. More fully automatic, so to speak!

One last note.... I'm a NAZI when it comes to keeping battery cables ONLY connected to our batteries. POS/NEG Batt cables ONLY!
Any Accessory circuits can be supplied via the rear "common", #1 or #2 terminals of our MBSS's.
#1 and/or #2 become schematically the same as though they are direct battery connections, but eliminate the typical "Rat's Nest" that we all too often see at Marine Battery Banks...... avoids small terminal corrosion as well.

#1 and #2 will be "Un-Interruptible" (charger leads, bilge pump float switch, radio pre-set memory, etc).
The Common terminal will be "Interruptible" (anything that we want OFF when the boat is unattended... such as our Nav Electronics).
All else will likely be a part of our OEM hull harness (cabin lights, frig, helm power, Nav lights, and so on).

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The Blueseas is good stuff.
The old black bodied Cole Hersee is good stuff as well (fully serviceable too).
Guess is OK.
Perko is low on my list of MBSS's.

I've cut all of the above open to look at the construction.

Again.... just a thought on that!


I'd post some schematics, but you have not asked for any. I don't want to confuse the issue any more than this can already be.

Good luck with this.

.
 
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Ricardo thanks for all the info. As I am merely a weekend electrician, from looking at your comments and Blue Seas website it states the ACR

"protects sensitive electronics by temporary isolation of house loads from engine circuit during engine cranking"

so can I install just the ACR to resolve my issue and just keep my current setup? If so how/where is it installed? Would like to keep as simple as possible. A diagram based on mine would be great!

The existing parallel switch is just a momentary button on the dash that can use if one side dies.
 
I'd go the separate house battery route and then install an ACR to keep it charged via the alternator. This should eliminate the electronics resetting when starting the engine. Connection could be to either alternator and you could add another ACR to provide the house bank with charging current from either alternator. The key to getting the ACR to function optimally is to maintain the same battery 'type' thruout (all lead acid, AGM, or GEL).

As far as the mystery box, a picture may help as well as the details on which wire connects where. May also need to measure the voltage to finalize its function.
 
All the suggestions above are great. I agree with comments about the ACRs, good upgrades. Some also have the ability to manually parrallel banks. What I want to point out in addition is that your symptom can also be caused by a poor DC supply. May be insufficient DC capacity to maintain proper voltage during start up without a significant voltage drop. I also find that typical electronics installations are hooked up with insufficient gauge wire. This will most deffinately affect the voltage reaching the electronics, especially when a heavy load is applied elsewhere. Though one may think a decent gauge wire is used from the electronic device to the closest positive and negative points say behind the dash (not always the best place), what gauge wire is supplying those points initially from a DC main? That is usually the oversight. You would also want to make sure your main battery cable lugs at the batteries and starters are clean, tight and of adequate size as this will draw more amperage than normally required. A friend hooked up a very expensive sterio only to be dissapointed when turning on engine, fresh water pump, bildge pump etc. the radio or CD would simply cut out. Told him to make sure the ENTIRE circuit supplying radio was of adequate wire size and after a few changes, no more cutting out.
 
And THAT is why I will typically suggest that we run a brand new, fresh, dedicated, proper sized circuit forward for electronics..... and to a brand new dedicate fuse panel...... 6 gang.... 8 gang.... whatever is required!
Power this new circuit from the rear of your MBSS from the terminal that directs this to the intended battery bank..... usually, the House Bank.
This prevents us from making any direct battery connections, and the Rat's Nest that goes along with it. :mad: :mad: :mad: (not to mention small wire terminal corrosion that can occur at/from a direct battery connection)

This also removes the OEM hull harness (and subsiquent harness connections) completely out of the loop.
If your hull harness power were to go down, you'll likely still have power to your Navigational and Comunication Electronics.

I'm not suggesting that this alone solves a low voltage issue (during engine cranking), but it is certainly a step in the right direction, IMO.

.
 
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