Will a larger battery bank maintain voltage level better than a single battery?

[MJH]

First, it is the size of the battery Ah rating rather than the number of batteries in the bank, i.e. a single 8D will have more AH than two size 27 batteries. Furthermore, bigger is better; that is, having the same amount of AHs in a singe battery is better than having it spread between two or more batteries.


That said a new 8D should be able to power a winch. I would check the circuits that the winch and chart plotter are connected to. If they are connected to the same one the 75Ah draw will pull from the other whatever it needs. Example, my windlass is connected to my house bank of 2 x 8D gel batteries (450Ah). For convenience sake I also connected the anchor washdown pump to the same circuit. This results in washdown pump interruption whenever I use the windlass even with the engine running...it makes sense and something I will correct one of these days.


Good Luck.


~ ~ _/) ~ ~ MJH

[john61ct]

Originally Posted by MJH

having the same amount of AHs in a singe battery is better than having it spread between two or more batteries.

What an odd idea, what makes you think so?

A string of 2V cells is much easier to deal with for a larger bank than just one batt at higher voltage.

If you're saying "do not put too many strings in parallel" then I agree, but that is due to balancing problems.

[MJH]

Originally Posted by john61ct

What an odd idea, what makes you think so?

A string of 2V cells is much easier to deal with for a larger bank than just one batt at higher voltage.

If you're saying "do not put too many strings in parallel" then I agree, but that is due to balancing problems.

I would agree with you that smaller batteries are individually less bulky to deal with than the larger ones (I dread the day I have to replace my two 8Ds gels at 160 lbs. each), albeit more cabling will be required.

~ ~ _/) ~ ~ MJH

[GILow]

As a few here have pointed out, the cable run to the winch is not likely to be the culprit.

But something to consider. I have read a lot of discussion on older Raymarine chart plotters like my C120 becoming temperamental with age. Mine gets very stroppy about all sorts of things now, particularly when there is a lot of traffic on the seatalk network. My recent addition of AIS data through the NMEA port has only added to the problem and sometimes it will reboot without warning, usually when it is cold.

[mickt243]

The problem may not be voltage drop as such, it may be transient voltages caused by switching the highly inductive load of a winch motor.

First up, I’d put a decently large capacitor across the power connections for the plotter and maybe a reverse biased power diode across the power input to the winch,

[saillr]

<<I also use a battery booster buck regulator to maintain a minimum voltage of 13.0 volts into my autopilot, chart plotter, and SSB transceiver; regardless of my battery voltage (down to 10.5 volts). All of my autopilot problems went away once I implemented that, and my SSB maintains 100 watts output regardless of battery state.>>


Capt Pat, You obviously know your battery/DC stuff. This reply is a little off thread but not sure where or how to contact.
I was unaware of Buck-Boost DC to DC regulators and would like to set up something similar. I too am a ham running an ICOM IC-7000 and all the other stuff like autopilot etc. Recently on a singlehanded voyage from Mexico to HI and AK I had a few problems but mostly with noise generation from the frig compressor. I have tried many things to relieve the problem such as shielding etc. To protect the source voltage to the radio I would like to include a Buck-Boost DC to DC regulator but have trouble locating one capable of 13 volts and the current capacity of the radio/autopilot/refer etc. Can you suggest where to find one and a brand?

[Gordon R]

Hello

Victron make very good reliable isolated 12v DC/DC converter. its called an Orion TR 12/12-9. They are bomb proof and I have fitted a few myself on various jobs. They have a max continues current of 9A and you can adjust the output voltage between 10 - 15v.


The incoming voltage can range/fluctuate/pulse between 8 - 17v but it will always output the constant set voltage.

Very simple to install. Just a plus/minus input and a plus/minus output. And also a separate little terminal that you can use if you want to remotely switch it on. Otherwise its good to go straight out of the box.


IMO a must for any sensitive modern electronics these days. I fit a lot of them for CCTV DVR's on boats and they run 24/7 in warm confined spaces and never ever falter.

BR
Gordon

[Cadence]

Not to course drift. What is the state of charge for storing lithium ion batteries?

[Cpt Pat]

Originally Posted by saillr

<<I also use a battery booster buck regulator to maintain a minimum voltage of 13.0 volts into my autopilot, chart plotter, and SSB transceiver; regardless of my battery voltage (down to 10.5 volts). All of my autopilot problems went away once I implemented that, and my SSB maintains 100 watts output regardless of battery state.>>


Capt Pat, You obviously know your battery/DC stuff. This reply is a little off thread but not sure where or how to contact.
I was unaware of Buck-Boost DC to DC regulators and would like to set up something similar. I too am a ham running an ICOM IC-7000 and all the other stuff like autopilot etc. Recently on a singlehanded voyage from Mexico to HI and AK I had a few problems but mostly with noise generation from the frig compressor. I have tried many things to relieve the problem such as shielding etc. To protect the source voltage to the radio I would like to include a Buck-Boost DC to DC regulator but have trouble locating one capable of 13 volts and the current capacity of the radio/autopilot/refer etc. Can you suggest where to find one and a brand?

I have had two of the "N8XJK 12Volt Boost Regulators" installed on my boat for 6 years. One for the autopilot, and one for my radios. Without it, my SSB will only output 100 watts when the batteries are at or above 13.5 volts. The other boost regulator solved all of my autopilot (Tiller Pilot) issues, including glitchiness in my autopilot when I transmitted on the SSB. You can find some reviews here: https://www.eham.net/reviews/detail/6449. I don't know if they are still in production, a search reveals something similar from MFJ: MFJ Enterprises Inc.. (Caution: I'm not a big fan of MFJ product quality.)

Noise is best attacked at the source (your frig) not the load (your radio). I have used several torroids, Digikey 240-2120-ND (just Google that to get a spec sheet) to successfully suppress brush noise from motors. They're cheap. I also place the same at the supply leads to RFI sensitive devices. They are far more effective than snap-on ferrites. Wrap both the positive and negative leads in parallel around the torroid (not just the positive lead - that config will saturate the torroid making it useless). Use as many wraps as you can. Leave some space between the "input" and "output" to minimize capacitive coupling.

The main source of RF noise, on many boats I've helped with, was caused by LED lights. I've seen some LEDs that completely wipe out the VHF band (including AIS) to such an extent that the skipper had two choices: 1) receive on the VHF radio, or 2) turn on his navigation lights. See USCG Safety Alert 13-18 for details: https://www.dco.uscg.mil/Portals/9/D...-16-091109-630. By the way, most Class B AIS transceivers use CSTDMA (carrier-sense) and will stop transmitting with high RF interference nearby. So, not only can't you see vessels on your AIS, they can't see you either. There are some very RF-quite LED lamps, and some that are all-band transmitters. Stick with name brands, avoid plug-in replacements for incandescent lamps. The FCC doesn't require testing of LEDs, so your selection process will be by trial and error. Hopefully the error won't involve a cargo ship. The European Community does require testing, so if you see the "CE" mark, that's a good indicator.

[john61ct]

Originally Posted by Cadence

Not to course drift. What is the state of charge for storing lithium ion batteries?

Not over 50-60% say most.

Lower the better say many more recently, as long as you take zero chances letting self-discharge drop below 12V.

Isolated from everything including BMS and cooler the better.

[Cadence]

Originally Posted by john61ct

Not over 50-60% say most.

Lower the better say many more recently, as long as you take zero chances letting self-discharge drop below 12V.

Isolated from everything including BMS and cooler the better.

Thanks, that is what I was lead to believe. Seems backward when you are use to lead acid.

[dbraymer]

"Pretty sure" that the wiring is sound is not really sure enough. The people that wire boats are working by the hour. I would first be sure that there was no "twist/fold" in the wiring to the windlass. This is where the installers do not unroll the cable properly from the spool, they pull on both ends of the cable that is actually formed into the original spool helix, and the cable gets a little kink, and the electrons run into an electrical "knot" in their path. Eventually the windlass wont even run, even though it shows proper voltage. Been there, done that, and that was quite an invoice for cable in the USVI.

Per previous replies, always a good idea to be running the engine while using the windlass. if the windlass motor fails, or you end up lifting a sunken destroyer from the depths, this can really hit the batteries hard. A good alternator can help the situation immensely.

[NYSail]

Check your ground wires to your engine.

When I first bought my boat I had this problem.... 2 4d agm lifeline batteries.
th batteries are 5 years old and assumed they seen better days (which they have) however at the advise of some real smart folks (Maine sail / Stu) I thoroughly checked and cleaned the ground wires from battery to the engine ground..... cleaned all terminals and also had to replace 1 wire. And while some of the connections looked fine from the outside, still disassembled attachments and found a lot of corrosion. Since then never have the problem even when batteries are down 50% and I’m on the hook pulling up anchor with idle at 800rpms. And my H3 windlass is about 27 feet one way to the bow away from batteries (4/00 wire)

So start simple and check connections to your grounds and go from there.

Good luck!

Greg

[Cadence]

Originally Posted by NYSail

Check your ground wires to your engine.

When I first bought my boat I had this problem.... 2 4d agm lifeline batteries.
th batteries are 5 years old and assumed they seen better days (which they have) however at the advise of some real smart folks (Maine sail / Stu) I thoroughly checked and cleaned the ground wires from battery to the engine ground..... cleaned all terminals and also had to replace 1 wire. And while some of the connections looked fine from the outside, still disassembled attachments and found a lot of corrosion. Since then never have the problem even when batteries are down 50% and I’m on the hook pulling up anchor with idle at 800rpms. And my H3 windlass is about 27 feet one way to the bow away from batteries (4/00 wire)

So start simple and check connections to your grounds and go from there.

Good luck!

Greg

4/0 is about a busbar. Kudos, skimping is ridiculous.