37 PC Battery configurations and charging issue


NH-PC

NH-PC

New member
So, I am new to the 37 PC After 30 years of boating and 3 other boats (I keep them a long time) I finally graduated to my forever boat and my first Formula. Been waiting a long time for a Formula.

As a new boat of course there are issues - to be expected. Even w a surveyor and 2 mechanics fixing everything we missed this one. On the test drive, after being charged on AC, the electronics all crapped out, dead on the 12volt. It was thought this was a battery issue but it wasn?t. 5 batteries later and I own her now the same thing. On Vessel View the starboard's voltage will go to 13.8 but port will go down to 11.x and DC items slow then stop, including all dash Gauges.

I spoke to Thunderbird support, and they clarified the following locations - looking from the back.):

- The 1 to the right (hull side) of port starts port
- The 1 left of starboard (hull side) starts starboard
- The 2 in the middle between both engines wired in series are for house "only"
- The one by itself forward of Starboard is for the generator.

They also said (1) both alternators charge house and that (2) in my config house is not shared with started batteries.

These 2 points don?t seem correct in practice. They obviously know there stuff but w different boats being wired differently, based on options, and getting info second hand from someone else putting down the phone, does this ring true?


With both alternators putting out proper charges while running I still go dead w just cabin lights, bilge, 1 cabin refrigerator and radio all in a few hours w the new batteries? this can't be right is it? I have proper battery types too.

Thoughts on this...

(1) Should it die this fast? Do yours? Does your Port go to 11.8 or 12 like mine and alarm low battery

(2) Do both engines charge house while underway or just one (port), or neither like mine seems

(3) Does anyone have this 5 battery config config and if so are the 2 house batteries shared w any engine when not in parallel? Likely in parallel all 4 are shared but without parallel, in the 4 battery configs is house and port tied together? Not sure why house goes dead AND port is low voltage. The BUT in here is when house is dead Port starts? 2 different problems maybe> The port being low, but starting , and house being dead? The low port side in Vessel View make me thing Port is tied in w house some how? I have run in parallel and not and the outcome is the same.


oh, and I thought I would ask. Do you turn off the 12 volt under the sink when at dock and on AC? I was told not to as there is a relay for Bilge there but I always thought both Bilges were wired past any switches and always on... What is best practices here.

She is SOO beautiful but tired on coming home dead with engines that always start.

Thanks all
Steve
 
That is similar to the way our 41PC is wired. BUT is the boat new or just new to you? I ask because if it is just new to you some PO may hav changed the setup. What type of batteries did you put in for the house bank? Not sure how Formula is distributing the charging from the engines but that would be an area to check and make sure that the house batteries are indeed being charged.
 
With all due respect to Formula TAG, I would caution you on taking their info as gospel on this issue. They are typically a very good source, but the information isn't always absolute, as there seems to be some variations from hull to hull on some occasions. Beyond that, your vessel's battery/charging system could have been modified by a previous owner. All being said, an electrical audit of your vessel's DC system might be in order before proceeding. Best of luck getting it resolved.
 
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Thanks for replying Comodave. The boat is new to me, so I’m figuring out these challenges even though I paid for two different mechanics to check the boat out. When were I bought it and one here my mechanic. They did fix a lot of things that were valid so some stuff got missed and I expected that.

I forget the exact battery models at the moment but I went down that whole path and the house batteries are highly rated appropriate deep cycle.

I think it’s making more sense now because I checked more carefully with a voltmeter and even though both alternators show consistent power all the batteries sets have different voltages such as the two house batteries in Siri‘s are a slightly different voltage than the port battery, so that means they’re not connected

So it seems like two different problems the house batteries are only being charged when on AC
<and> The port battery is only being charged on a AC or unless I set them in parallel.

so I’m thinking the two different problems have the same source and that though the generator on the port side is making power it’s not reaching the port battery or the house batteries

when I explained this to formula when I was asking about the battery layout they said they really don’t know but suggested maybe I need to buy this : integrated relay. I’m wondering if the boat has two of these one for each alternator and this is what’s stopping the power from making it to the batteries

INTEGRATOR RELAY TYCO EV200AXANA02
 
That’s the feeling I got as well after talking to formula, he even said our electrical diagrams are general guidelines but we do build them differently. This is something new to me as other builders have very specific documentation but these things seem to be really handbuilt, which I’m fine with. And that’s what I’m trying to do is figure out the whole system before doing much and as mentioned above I think I’m onto something, I suspect the port charges the house only and something is stopping the house and the port engine battery from charging Even though I’m getting 14.3 at the alternator
 
I had what appears to be a similar issue on a 31pc. Batteries charged fine with shore power but not - as I was to learn after the fact - through the alternators. Not good at all when BOTH engines died while making a U-Turn in congested Ego Alley here in Annapolis.
Limped home on one engine after a magical restart and later found that each engine has a main 50 amp (??) breaker that interrupts current from alternators to batteries. Both had tripped when I was installing a new ProNautic charger. Mechanic reset them and all was well.
Since he found and resolved the problem when I wasn?t there I do not know any more details than the above.
I share this at the risk of sending you down a rabbit hole that has nothing to do with your issue, but also to give you another data point in your troubleshooting.
Good luck.
 
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On my 34 PC, the documentation shows 4 batteries, Starboard start, Port start/house, House and generator. Port start and house tied together by ACR. The way the boat actually was built is Starboard start, Port start/house, 2 house in parallel, with ACR tying in the port start, then generator. Also a parallel switch for emergency start, tying port and starboard. Lesson being that the documentation isn't necessarily correct. I'd start troubleshooting by running one engine at a time, taking voltage readings at various spots, (alternator output, battery posts, battery switch, ACR if you have one) Take one set of readingings then increase RPM and take another. Do this on both engines, individually, then with both running. Repeat voltage tests with engines off and shore power on, to verify charger.
 
GandDFreehold said:
On my 34 PC, the documentation shows 4 batteries, Starboard start, Port start/house, House and generator. Port start and house tied together by ACR. The way the boat actually was built is Starboard start, Port start/house, 2 house in parallel, with ACR tying in the port start, then generator. Also a parallel switch for emergency start, tying port and starboard. Lesson being that the documentation isn't necessarily correct. I'd start troubleshooting by running one engine at a time, taking voltage readings at various spots, (alternator output, battery posts, battery switch, ACR if you have one)
Click to expand...

Mine is reasonably similar to yours. Out of curiosity, where is your ACR located?
 
Thanks all for this help. I've got some of it figured out w your assistance. We made some progress and the local Formula dealer found a bad 100 amp fuse. Still a lot of this is a mystery and the local dealer needs to take another crack but they said they could spend a day and accomplish nothing. A true and fair statement but I’d like to see what I can do here myself, plus they aren’t free for a month.

Here are some updates and what is less


  • Both generators put out proper voltage and amps. The motor batteries charge solid now (thanks Steve).
  • A corroded wiring block being cleaned woke up a lot of the boat
  • The 100 amp fuse fixed a problem I thought wasn’t related. The Starboard starter motor the gear would not fully engage making the boat sound like a bad flywheel

So here is where I am now. It feels like there is a device between the power sources and the house batteries:

  • The House batteries are not charging from running engines though generator charges engine batteries fine. Zero voltage change there at house.
  • The House batteries are not charging from Generator when powered on from the cabin. It starts and shuts right off showing a voltage change to the battery for seconds. No error on the generator display too. If the generator is manually started it charges the house batteries great!. So to go boating I have to wait until the house dies, accompanied by al gauges, and sit there and let the Generator recharge the house to get underway – or not have gauges.
  • The 12 volt systems does not get power from shore. All 12 volt is off when the battery under the sink is off


Is this all the ACL? Whatever that is or where it is located?
thanks again
 
You can google "auto charge relay", good info on the internet. Basically it should monitor voltage on "preferred battery" when that voltage reaches a predetermined setting the relay closes and allows the other batteries to charge. Usually the preferred battery is the engine start battery. I'm not at the marina so I can't give you a brand name at this time.
That being said, if I recall, with my setup, there are isolation breakers at the ACR that must be on in order for it to pass voltage.
You are correct, when battery switch under the sink is off all 12 volt systems will be off. (other than emergency systems, aka bilge pumps.
You should be able to locate the ACR by following the wire back from the battery. One wire should feed house systems the other should come from the ACR. (both wires, I believe are the same size.)
 
This was it, thanks all. The ACR starting motor side reads12-13.x depending on running or not and the house might be 8-12 and never matches the other side. Simple in the end. I really do need to learn all this stuff myself don't I and it's not that bad.. Formula can't get that part any more but this is what they recommend and it's half on Amazon vs elsewhere at $156?
the The 7622 has an override to put both together if it fails. The 7620 does not. Looks like good stuff and what Formula uses now:
https://www.amazon.com/gp/product/B001VIXLRO/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&th=1 f

For those that need it here is the ACTUAL wiring of a 37PC from them, w Axius. This is exactly correct and I've seen nothing like this elsewhere so maybe this will help someone else. Thank you Thunderbird for this one.
https://drive.google.com/file/d/1aO_hgLPBJr-zO8jMTOsPwv06ZvdwhN4-/view?usp=sharing

Also, here is the Pierogi. Yes the word Pierogi is not in the Coast Guard list of registered vessels anywhere :) My wife is 99.8% Polish and happy wife, happy boating life :)

https://drive.google.com/file/d/13US7JiMjpcL8Qi9C75cZ78bUyVj3m7tf/view?usp=sharing
https://drive.google.com/file/d/1LrAHj7iFmJP10_8yLQ3hBwu8HyyqYNcu/view?usp=sharing

I started w 5 wiring issues and am now down to 2. As of next week I can start having the house NOT die after an hour once the part gets in and I pop it in on Friday. I might as well keep these going here 2 left!

(1) With the 12 volt being shut off under the sink , shutting 12 volt shuts all 12 volt off, makes sense. The dealer said it should NOT work like this and 12 volt should be live in this condition. Being off is what every other boat has done for me granted the gerator and more complex AC charging is new to me. I think I need to ask another person at the dealer :) So it trickles in from the charger to the batteries and draws from the batteries the same was. The only 12 volt I really want is the fridge. OK, if this is normal, the last 12 volt bit here is that why would my house batteries die after 1 to 2 hours of use (when they are NOT charging as it's been) ? I need to do an amp test for any parasitic draws (something drawing un-needed) I have 2 new correct deep cycle batteries. How long would a similar boat with the fridge, all dash equipment including Radar, maybe a few lights run on 2 house batteries? Maybe this is normal?

(2) My FINAL wiring issue. The Generator... Moving this to the generator forum. I'm thinking it might be better there. http://formulaboatsforum.com/VBFORU...s-from-Cabin-if-set-to-Auto&p=89573#post89573

slow but sure the Pierogi will regain a full life. Thanks again all
 
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Here is another diagram from my 41 PC. I am having same issue. FWIW. I am purchasing Victron 712 and installing this weekend. WIll advise.41 pc charging.JPG
 
That was it, it?s super easy to test in the end with a voltmeter, check both sides, and you can even jump both sides with a wire to charge the house batteries.

Of course if you hotwire it you don?t have the production of one side being really drained hurting the other or the engine cranking spiking something on the house battery side
 
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