Battery Charge Alarm

[Maine Sail]

Originally Posted by Sun and Moon

Maine,
Is the ACR smarter than a diode? Can it put the start battery on float when the rest of the system is on bulK? I guess I'm wondering why the start battery doesn't get overcharged when the house bank is receiving a bulk charge. Or maybe the depleted house bank pulls the input voltage down during bulk charge so the ACR doesn't turn on? I'm hoping you can clarify for me.
Thanks!

They are just different. A diode isolator charges batteries in isolation from each other. An ACR/VSR/COMBINER charges the batteries in parallel (think of an ACR as an automated BOTH switch) thus the batteries both charge at the same voltage together and enter float together. With a properly installed ACR the batteries will be at pretty much identical voltages thus you can't "over charge" one bank without also over charging the other bank...

[kas_1611]

Couple of things to point out:

1) All 3 of my battery banks are independent. They have individual isolator switches with no way to cross connect. In other words it is not possible to start the engine from the house battery or power the thrusters from the starter (unless I use jumper cables).

2) I do not want to "over" charge any battery

3) Current isolator diode is in the engine bay with feed in direct from the alternator and 2 feeds out to starter motor then onward to start battery and to house (and thruster via second isolator). Alternator senses voltage from the house battery.

4) House and thruster have never been exposed to more than 14.4v while under engine charge as indicated by my external battery monitor (cross checked against multi meter). Starter battery is getting hit (intermittently) with up to 15.5v under engine charge. This is voltage at the terminals.

5) House battery is also charged from 2x35W solar panels controlled by independent charge controller.

I'm looking into both the Sterling ProSpllit R system and the Merlin SmartBank system as replacements for the diode isolator. If anyone has experience of either of these or other similar systems or of smart alternator regulators/charging then all advice gratefully received into the communal consciousness.

Cheers

Keiron

[d4raffy]

Originally Posted by kas_1611

I'm looking into both the Sterling ProSpllit R system and the Merlin SmartBank system as replacements for the diode isolator. If anyone has experience of either of these or other similar systems or of smart alternator regulators/charging then all advice gratefully received into the communal consciousness.

Obviously, I have 😃
I have a Sterling Alternator to Battery charger (A2B 160) - charging Service and Engine
To a ProSplitR 120 charging Thruster / Windlass
A Sterling Battery to Battery charger charging an Aux bank from the Service
A Merlin Smart Gauge monitoring the Service and Thruster & a Mastervolt monitoring the others
And a 3 way 240v charger from shore and generator.
And solar .... MPPT & PWM
Not sure I would stick with this - ideally - but I have my reasons ......
All works for me .... So far ... Happy to show and tell in next few weeks ?

The 'rub' is ... if you have a mix of battery types - then you 'ideally' need 'intelligent' chargers for each type.... And do you have an alternator that allows external regulation - you do - so happy days.

Look at Adverc and Merlin Smart Bank....... Maybe

Tally-Ho


Sent from my iPad using Cruisers Sailing Forum

[kas_1611]

Damian,

You show and tell, I'll bring the beers

With 2 lead acid batteries and a set of AGMs I could do with a "smart" charge system to get the best out of the engine charge and to avoid any damage to the AGMs. However as it stands at present with the thrusters (AGM) getting their charge supply from the house side they have never been exposed to excessive voltage.

Primary task is to replace the diode isolator with something better to fix this overcharge problem then I can look into a complete overhaul of the charge system over the winter.

Cheers

Keiron

[hellosailor]

Keiron-
Removing the isolator, moving the voltage sense lead to the house bank, and installing a Yandina (also sold by West here) combiner with up to 150A capacity, could be the simplest solution and a very effective one.


The Yandina combiner (the principals do come here from time to time) is time-tested and reliable. Once your house bank sees something like 14.1 volts from the alternator, the combiner closes and connects a second battery (I.e. your starter) in parallel. The hungrier battery, presumably the house bank, will absorb more charge so they stay in balance. When you shut the engine and the battery voltage has dropped to something like 13.8V, it disconnects them, so they cannot both be pulled down. The different voltages are enough to prevent any "chatter".

Normally you'd connect to the starter battery and connect the combiner to that, so the starter battery charged up first, but that's a priority you can decide.

Then charging the AGMs for the windless is just another option. You can tie them in to the start battery, switch them manually, or use another combiner, or the lower-power echocharger, to bring them in automatically. Your choice of whatever is simplest. I would suspect that the voltage drop in the long wiring run going forward to the AGMs, will serve to reduce the alternator voltage from "wet lead" to something tolerable for the AGMs. That's easily checked with a meter.


The Yandina combiners are...hazy memory...maybe $1 per amp with new/old models ranging from 75A to 150A capacity, you can check their web site. And they're quick to answer questions.

[kas_1611]

Finally back on the boat so have traced and measured all the important wires in the engine charge circuit.



No I have no idea why this is on a black background before anyone asks and yes I know there's no electrical symbols but I hope it's self explanatory. I have tried to indicate the relative thickness of the wires.

Using the circumference of the wires with the insulation I come up with 3 different sizes; 20mm, 40mm and 54mm around. This gives a CSA of 31.8mm2, 127.3mm2 and 232mm2 respectively and according to an online conversion based on the closest diameters and areas gives AWG numbers of 3, 4zero and 7zero respectively (although I admit there is room for error in that calculation as I am not sure how thick the insulation is).

The thinest "wires" on the diagram represent the 20mm circumference and the thickest the 54mm circumference. In effect the wiring from the alternator to the house battery is composed entirely of 40mm circumference or AWG 4zero. This is a long cable run which I estimate to be 4.5 to 5m.

At the moment I am thinking I will change the diode isolator for a Sterling ProSplitR and add in either the Sterling smart regulator or the Adverc system to control the charging of my 3 battery system.

Last thing for now I have checked the starter battery and it is holding 12.6v after nearly 3 weeks isolated from any charging system. This suggests that it has not been badly damaged by the high voltages seen previously.

Cheers

Keiron

[hellosailor]

You show an engine ground that is not connected to anything, and the alternator connecting to both sides of one battery, presumably ground and hot, while we're left to guess everything else is grounded maybe to the engine ground separately? Risky to make assumptions that way.


Also, as you note, measuring wires with the insulation on them only guarantees they are a smaller gauge than what you've measured, it doesn't give you any real good information.


So as you get a chance, keep at the diagram. Replacing the diode isolators will at least bring you into the late 1900's (G) instead of 1950. That you're starting battery has kept 12.6v, even under no load, does indeed indicate that, as Monty Python said "It's NOT dead."(G)

[kas_1611]

Originally Posted by hellosailor

You show an engine ground that is not connected to anything, and the alternator connecting to both sides of one battery, presumably ground and hot, while we're left to guess everything else is grounded maybe to the engine ground separately? Risky to make assumptions that way.


Also, as you note, measuring wires with the insulation on them only guarantees they are a smaller gauge than what you've measured, it doesn't give you any real good information.


So as you get a chance, keep at the diagram. Replacing the diode isolators will at least bring you into the late 1900's (G) instead of 1950. That you're starting battery has kept 12.6v, even under no load, does indeed indicate that, as Monty Python said "It's NOT dead."(G)

I never claimed to be an electrician so don't expect electrical diagrams. I'm also not a mechanic so I might get the names of engine parts wrong. For that I can only apologise. I'm a geologist so if you want a sketch of the San Andreas fault line in 3D then ask away. So I didn't mark a positive and negative on the battery but then I figured it would be pretty obvious given the colour of the wires I used.

Forget the rest of the system and concentrate on the starter system. The alternator connects to the diode isolator directly then from the isolator to the starter motor. This uses 12.7mm OD wires (that is 40mm circumference including insulation). From the starter motor to the battery via the isolator switch uses 17.2m OD (54mm circumference) wiring with the ground wire retuning straight back to the ground point on the starter motor/flywheel(?). Right now I have no other way to determine the size of the cables other than measuring their external circumference as I am not going to start taking the system apart. Despite what others have said there are no markings on the insulation to give me any idea what gauge the wiring is.

This is the critical system at present as it is the one we are seeing the high voltages on.

The alternator has a separate ground wire that is connected to the engine block. Every other ground wire that comes into the engine bay connects to the ground point on the flywheel(?). Either way everything is grounded somewhere to something.

I hope the photo below helps in the understanding of what is wired up to where on the engine block.



Finally can I ask that we get away from the snide comments about diode isolators being old fashioned or that Replacing the diode isolators will at least bring you into the late 1900's (G) instead of 1950. I have already stated that I intend to replace the isolator with a more modern system so there is no need for these negative comments.

Thanks

Keiron

[Sun and Moon]

Kas, I have to say I'm a bit surprised at your attitude. You say "I never claimed to be an electrician so don't expect electrical diagrams." and then "So I didn't mark a positive and negative on the battery but then I figured it would be pretty obvious given the colour of the wires I used."

So you make up your own way of drawing diagrams which includes obvious flaws such as multiple wires going to one battery and single wires going to other batteries. We might guess that red is positive and black is negative, but what are we supposed to think about pink? I'm in the Bay area, so I might think it swings both ways. Then you complain about people labeling your current system as 1950's technology. Guess what - it is 1950's technology!

There are people that have tried to help you solve your problems that are highly skilled professionals. They can and do charge a lot of money for their services, but they have volunteered to help you for free! You'll get a lot more value by dropping the attitude and putting in the effort to communicate in the accepted standard way (ie learn how to draw proper electrical schematics). Maybe then you'll learn how to fix your boat so it doesn't destroy batteries or catch fire.

[kas_1611]

I am extremely grateful for all the advice and help I have received from everyone. Trust me I have learnt more about this than I imagined.

And I am sorry for my lack of skill with electrical diagrams but as I am not an electrician I have no knowledge of the rights and wrongs or what symbols mean what. Hence why I tried to keep it as simple as possible because had I got the wrong symbol in the wrong position it would have been even worse.

The pink wire leading to the top battery is the Alternator Regulator sense wire.

I agree I should have labelled the batteries better but the one with no apparent ground is the thruster. I included it to show how it was wired in through a separate isolator off the house live. I can assure you that it is grounded.

I am aware that a diode isolator is old technology and I am going to replace it with something more effective and up to date. That is why I asked that we drop the comments about it as I felt that continually mentioning it was detrimental to the thread

I apologise if anyone has taken umbrage or offence as that has never been my intention.

[hellosailor]

No one faults you [geological pun intended] for being a geologist. Still, like electrica circuits, it is a physical science so your skill set should be able to deal with a charging system.


"So I didn't mark a positive and negative on the battery but then I figured it would be pretty obvious given the colour of the wires I used." Well, again, that can lead to assumptions if there are non-standard colors (like purple from the alternator?) and no labels to confirm with. There's always some oddball setup. Volkswagen used positive grounds in their cars long after the rest of the world had gone to a uniform negative. Toyota wires their headlights with switched ground instead of switched positive. If you don't arbitrarily know that...Ooops.


So the labels help, for the same reason you'd want labels on any field sample or specimen.

" Forget the rest of the system and concentrate on the starter system."
Probably right--but a risky assumption. Integrated systems do, after all, share integrated problems.


"The alternator connects to the diode isolator directly then from the isolator to the starter motor."
Taken in isolation, that would make no sense at all. The alternator can and arguably should go directly to the starter, there's nothing to be gained by putting anything in the way.


"Despite what others have said there are no markings on the insulation to give me any idea what gauge the wiring is." I've seen wires where I needed my reading glasses AND a magnifier AND a torch to read the faint print or stampings on the wire. But if there's really nothing at all, that's a warning to find out what you've got, because AFAIK all cable actually certified and intended for similar use, will have markings to show it is safe for the elevated temperatures and petroleum-fume resistance of engine bays, along with other approval stamps and the wire size. It sounds like someone bought a load of "machine cable" or welding cable.
There is also a good chance that the intended cables size is stamped on each of the lugs or terminal fittings, obviously you might need to unbolt those to read it.
If you had a good ohmmeter and a longish piece of cable (unbolted at both ends) you could actually measure the voltage drop or resistance of the cable, and that in turn would also tell you the wire size. Somewhat less complicated than xray crystallography but I understand not every geologist does that either.(G)

"This is the critical system at present as it is the one we are seeing the high voltages on."
And again, no pun intended, it isn't an isolated system. The alternator is sensing voltage, somewhere, with a voltage sense lead. You need to know where that lead is, and then consider everything between it, the alternator output, and your starting battery.

" The alternator has a separate ground wire that is connected to the engine block. Every other ground wire that comes into the engine bay connects to the ground point '
There's no harm in that. Most alternator installations simply ground to the block by their hardware, and the resistance is effectively zero. Having an extra ground wire, somewhere between redundant, overcautious, and pointless IF the alternator is conventionally installed.


Grounded on the flywheel? No no, flywheels move much faster than continents drift. I can't make out the thumbnail picture but will assume it is a ground point of some kind. The flywheel would be a large disc at the rear of the engine that helps it to spin evenly despite the uneven cylinder firing. Usually under a cover, usually with gear teeth on the outside rim of the flywheel as well, that are used for rpm sensing.


Again, it can be as simple as the alternator voltage sense lead being connected to the wrong place, but without seeing ALL the connections in the system? There's no way to be sure of that. That lead could be tied back to the main output lead six inches away from the alternator ("1-wire" system) or lead to any battery in the system ("3-wire" system) and if it is lead to only one battery and no accommodation made for other batteries/banks...that's just wrong. "Good enough" for light use and frequent battery replacement, but still "wrong".

[kas_1611]

Hellosailor - I would like to thank you for the geological puns (intended or otherwise) for making me chuckle. The world needs more laughter.

Can I go back in time and remove the diagram? No, oh well lesson learnt and I'll try harder next time. Oh and make sure it has a white background. No idea where the black background came from as it's most definitely white on my screen. Think I might just go back to describing sandstones and looking for oil

I can see markings on the insulation but nothing stands out as wire size that I can make out. TF Kable 3 BBJ HAR H07V-K and another as 0052M are all that can be clearly made out. Doesn't help that most of the cabling is hidden in cable guards.

A quick google and the H07V-K reveals the wires are DIN VDE 0281-3 and BS6004 rated for up to 750vDC (1000vAC) usage between -30ºC and +70ºC.

Time I think to go back to the original problem of what is causing the alarm.

What I can't get my head round is if the alternator is sensing the house battery (as it does directly) then if the house battery is full (14.2v) shouldn't the regulator shut down the charge?

So is the problem the isolator or the alternator? No point in spending my hard earned sovereigns on new electricky gizmos if the isolator (1950s technology not withstanding) is actually working fine. All the isolator is doing is splitting the charge and preventing the batteries from feeding back into one another. I am a great believer in "if it ain't broke don't f**k with it" and there's nothing wrong per se with old technology if it works. Yes it can be improved and I am looking to do that but first I need to figure out what the problem actually is.

I am beginning to think the problem may lie in the regulator but without removing the alternator and sending it to a specialist to test how can we check?

Many thanks again to all and if you ever need a rock describing give me a shout

K

[Stu Jackson]

What you need to begin to do is start writing and thinking about the FUNCTION of the wire, not just the size and color. In fact, size & color alone tell you nothing. You NEED to know what that wire did or used to do before you disconnect anything.

You HAVE TO begin to ask yourself this: “What does this wire do? What is this wire called?” Only then can/should you can identify it further by size & color.

Instead of reinventing the wheel, you could start here:

Basic Battery Wiring Diagrams This is a very good basic primer for boat system wiring: Basic Battery Wiring Diagrams

This is another very good basic primer for boat system wiring: The 1-2-B Switch by Maine Sail (brings together a lot of what this subject is all about)
1/BOTH/2/OFF Switches Thoughts & Musings - SailboatOwners.com

[kas_1611]

Stu,

Those diagrams are great if you have a 1/2/both/off switch, which I don't. All 3 of my batteries are individually switched on/off and have no interconnection with each other at all. In other words it is not physically possible to start my engine from my house battery without using (external) jump leads.

However I am sure others reading this thread will be able to use them so thank you for sharing the links

Cheers

Keiron

[hellosailor]

Stu makes a good point, if you disconnect ANYTHING, make sure to label the wire and the lug it went on, so it goes back in the same place.


"TF Kable 3 BBJ HAR H07V-K"
The reference I found for that says it is a 3 or 4 conductor bundle, much like a heavy duty appliance cord with three conductors in it.

I'd suggest further exploring, taking the numbers to an electrical supply house since they usually know what those mean. Or, slitting back some insulation to see what you really have. Are you sure a previous owner didn't cobble that wiring together?

"What I can't get my head round is if the alternator is sensing the house battery (as it does directly) then if the house battery is full (14.2v) shouldn't the regulator shut down the charge?" IF the alternator is in fact sensing the house battery, and IF there was nothing in between the two, and IF it reached the regulator set point, yes, that's how it works. But if there are two diodes, creating possibly a one-volt drop between the alternator and the battery, or the sense lead to the battery, then the system gets screwed up and "deceived" by the voltage drop from the diodes. (Which is why diodes are such a bad idea unless you've got a very simple unswitched system.)

"So is the problem the isolator or the alternator? No point in spending my hard earned sovereigns on new electricky gizmos if the isolator (1950s technology not withstanding) is actually working fine. " Well, a West/Yandina combiner might set you back $150. A second echocharger, another hundred. And by eliminating the diodes, you get to run the alternator COOLER and WEAKER so you get more fuel economy, longer alternator life, and more engine power available for other purposes. Not to mention, you don't have to screw around trying to custom kludge the regulator voltages and other issues.


" All the isolator is doing is splitting the charge and preventing the batteries from feeding back into one another." Nope. That's not what it is doing. It is doing that AND it is changing the voltage that different parts of your system are seeing. What should be one voltage to all charging points, is now three different voltages, creating charging mismatches, possible voltage loops, and other problems. You have noticed, there are problems, right?(G)


" I am a great believer in "if it ain't broke don't f**k with it" and there's nothing wrong per se with old technology if it works." Totally agree, but obviously it is NOT working. And cannot be readily made to work.


" but first I need to figure out what the problem actually is."
My point being, if you do not have the technical skills to document, diagnose, and repair an obscure and obsolete system, it will be faster, simpler, and cheaper to convert it over to a STANDARD contemporary system of higher efficiency and reliability.


Sure, I could dig coal, smelt iron, forge a new hammerhead and fix my old hammer. But I could save a month of hard labor by just going down to the store and buying a nice new one with a nice new handle for then bucks. The ten bucks is the LEAST part of it.

I am beginning to think the problem may lie in the regulator but without removing the alternator and sending it to a specialist to test how can we check?"