Should I fit a smart charging regulator?

[jonjo]

A recent long thread discussing the Sterling battery charger made me realize there are cons as well as pros to consider when thinking about fitting a smart regulator.

Over the weekend I let my domestic 140 AH battery run down to about 77% capacity with an associated voltage of 12.35v according to the Link-10 monitor. With all electrical demand off, at 1100 rpm my alternator pushed 39 amps into the battery at 13.95 volts. Higher revs did not improve the rate of charge but the charge current dropped off quickly under 1100 rpm.

My yacht is a 2 year old AWB that lives on marina shore power most of the time, maximum time away from 240v shore power is around 4 days, maximum likely motoring duration is 12 hours and I don't expect to venture further south than Brittany.

The domestic battery is a basic wet acid type that can be topped up.

My feeling is there is not a lot to be gained from a smart regulator given my modern charging setup and usage profile.

 

[FullCircle]

4 days is more than enough to flatten your batteries, and the alternator is ensuring that your engine bank is topped first and also(if you read the small print) normal alternator charging will not take your batteries over 75% of their true capacity, so the extra available to you helps tyou stay away from smelly marinas for longer.
In addition, the motoring charging profile assists the life of the battery by reducing the enormous chunks of energy, and lengthens the life of your alternator belt by reducing the initial loads and therefore the wear on the belt/pulleys.
Enough to make it worthwhile in my eyes.
I think its the best thing I have done so far.

 

[jonjo]

[ QUOTE ]
4 days is more than enough to flatten your batteries

[/ QUOTE ]
So true, SWMBO can knock off the daily x-word at impressive speed but feigns complete ignorance regarding lights, amps and junior school arithmetic.
[ QUOTE ]
(if you read the small print) normal alternator charging will not take your batteries over 75% of their true capacity

[/ QUOTE ]
If true I am convinced but my take-away from the mega Sterling thread is this 75% number only holds true for older charging systems with retro fitted split diodes and conservative charging voltages that originate from the auto world.

Anyhow I am off on a mini 11 day cruise in 2 weeks time which should at some point allow me to plot how effective the basic alternator is.

 

[pvb]

You\'re right...

You're right, with your current system and usage, there's not a lot to be gained from a "smart" regulator. A much more cost-effective improvement would be to increase the size of your domestic battery bank by adding similar batteries in parallel. This will improve charging efficiency and increase battery life.

With a Link 10 monitor, you're already able to see exactly what's happening with your batteries, so if you feel in future that a "smart" regulator will help, you'll know exactly why.

There are many misunderstandings about battery charging, and FullCircle's post includes a couple. First, an alternator will recharge a battery, it'll just take a long time using the standard-fit regulator. Second, "smart" regulators generally don't reduce initial loads immediately after starting.

But your best bet is to add 1 or 2 extra batteries before you do anything else.

 

[FullCircle]

Re: You\'re right...

No further comment....


Adverc Battery Management FAQ

Q1: Basically what does ADVERC do?

A1: ADVERC Battery management is a sophisticated alternator voltage regulator or charge controller which ensures batteries are 95-100% charged with minimum engine running time.

Q2: Why doesn’t my existing alternator do this?

A2: Because the alternator regulation is designed essentially for the motorcar. Used in specialised applications, such as marine craft, trucks, ambulances, mobile libraries etc., the battery state of charge only ever reaches 65-70% of its capacity, even with the engine running for long periods.

Q3: How does ADVERC work?

A3: The aim is to produce the optimum charging voltage at the batteries, not the alternator, compensating for voltage losses.

These voltages are cycled below and above the gassing point of the battery(s) to a given programme, also compensating for changes in ambient temperature, thereby achieving fast and safe charging.

ADVERC is NOT a BOOSTER. It is a CONTROLLER. There is no forced feeding in terms of charging current - the batteries only take whatever charging current they need.

Q4: Will ADVERC harm my batteries or alternator.

A4: No. Batteries and alternators last longer and perform better, in fact, as do starter motors, diesel heaters etc.

Q5: What happens if I have two battery banks?

A5: No problem. One ADVERC accommodates one, two, or more battery banks using various split- charging options eg blocking-diodes, 1, 2, both switches or relays.

Q6: Will ADVERC fit any alternator?

A6: Yes, though we need to know the make and other details to establish the polarity and provide the appropriate installation details.

Q7: Do I need to increase the size of my alternator?

A7: Not necessarily and probably not. By using ADVERC, the AVAILABLE battery capacity is more than doubled. On the other hand, the total battery capacity is the deciding factor. ADVERC cannot make the alternator produce more than its rated output.

Q8: Can it be used with twin alternators?

A8: Yes. One ADVERC system will accommodate two compatible alternators on the same engine, or a twin engine configuration. The system is ideal for catamarans, for example.

Q9: Can I use ADVERC with any type of battery?

A9: Yes ADVERC is suitable for flooded or gel types and the voltage settings can be adjusted for eg Ni-cads or special situations.

Q10: Can I install more batteries?

A10: Yes, if required. ADVERC will also accommodate multi-battery banks, using an appropriate split charging system.

Q11: Do I need to worry about high voltages affecting sensitive equipment?

A11: No. ADVERC ‘cycles’ between 14.0 and 14.4v at the batteries (27.5v and 28.5v for 24v electrical systems). These voltages are well within the scope of virtually all sensitive navigation and other equipment, unlike BOOSTERS which can deliver voltages in excess of 15.5 volts.

Q12: How reliable is your system?

A12: Very reliable, the concept and design based upon development since 1983.

ADVERC has a two year warranty and is specified or approved by most Boat Builders and Safeway PLC., Asda, Ryder Truck Rental, Group 4 and most Ambulance authorities. ADVERC has played a part in terms of battery charging on several Whitbread Yachts in the last two series.

Q13: But what happens if the ADVERC system fails?

A13: The latest Mk IV a unit works in tandem with the original regulator. In the unlikely event of ADVERC failure, the system reverts to standard regulation, providing a vital fall-back situation

Q14: Is it easy to install?

A14: The installation is straight forward and within the compass of a competent do-it-yourself enthusiast. Some alternators are easier than others. The first installation generally takes 3-4 hours. Full instructions are given.

Q15: Do you have Installation Specialists available?

A15: For total peace of mind we have around 150 Installation Specialist or Dealers, world-wide.

Q16: How do I know which ADVERC system to specify?

A16: Simply provide us or our Dealers with alternator details and any other background such as battery layout, capacity, method of split-charging etc., all of which helps us to provide the appropriate instructions.

Q17: What is the cost of a complete ADVERC system?

A17: From £177.50 plus VAT, upwards, depending on the system and ancillaries. This excludes installation.

Q18: Does your company provide other complementary equipment?

A18: Yes. We have been in the business of battery related matters since 1983 and can advise on or supply: Solar Panels, Wind Chargers, Split-Charging Systems, Monitoring & Measuring Equipment, Mains Chargers, Inverters, Converters, AC and DC Generators, Batteries and most things to do with this subject.

An ADVERC Technical Brochure is available on request together with information on the complementary product range indicated.

 

[bluedragon]

You might think that 13.95V is enough, and I suspect the 39A didn't last long before dropping-off dramatically, but that's exactly the situation I had last year and never felt the batteries were fully charged even after 12 hrs motoring. Sure they were "good enough" for the cruising I was doing, but having to run the engine more often than I liked in a peaceful anchorage I decide to fit a Sterling controller this year. What I've observed so far is at the pontoon (going off next week hopefully), but the rate of re-charge of a 50% discharged service battery pleasantly surprised me. This means a lot less engine hours simply to charge the batteries, and with a better state of charge, hopefully I'll maintain closer to 100% capacity for a longer time. So there's no simple answer here. I'm sure you'll be OK with what you have, but a Sterling or similar controller working at 14.8V MUST increase overall charge efficiency. Whether you'll see it and value it is harder to say.

Regarding belt and general stress on the engine, I switch the Sterling in about 5 mins or so after start depending on the degree of discharge on the batteries. When I do, I hear the revs drop and the alternator "whine" for a few seconds. It really can load the system. No problem with 30HP and multiple cylinders perhaps, but for an old single pot 8HP donk, it's a different story. In principle these things ramp-up to minimise belt wear, but I find I have to use my own manual ramp-up procedure.

 

[Gumpy]

Re: You\'re right...

Sorry but you are so wrong......

If a system does not have split charge diodes (dont start me on that subject) in it and has a new alternator that charges at 14.2v or above then buying any charge controller is just a waste of cash.
What you quoted was fron a site that is selling a product that is out dated and now with modern alternators redundent.
Sterling are the same.
Try this:
http://www.smartgauge.co.uk/controllers.html
From a site that does NOT sell alternator controllers.
I have been a livabord for 15years and I will admit that when I started I had a sterling controller as my alternator only ever produced 13.8v in its undoctored state so it served a purpose.

Now I do not run a smart controller even with my 24v 400Ah battery bank and 100amp alternator and never have a problem with lack of charge. In fact having a Smartgauge fitted tells me when the batteries are fully charged, my 65amp inverter charger refuses to get them above 96% even if left on float for weeks, where the alternator gets them to 100%.

If any one feels confident delving into an alternator then this:
http://www.smartgauge.co.uk/alt_mod.html
could be used to increase the charge.

Julian

 

[bluedragon]

Re: You\'re right...

Yes, I read the Smartgauge articles before buying the Sterling, and if the batteries actually see >14.2V then the case is diminished. My alternator regulator is I believe set at 14.3V, but best I see at the end of a relatively short cable is 14.2V, and then having gone through an ammeter, isolating switch and VSR, the overall voltage available for charging was 13.90-13.95V...and even the Smartguage people think that's a bit low from what I recall. I have improved the circuit now, and got the voltage drops down, but I think the main benefit of the Sterling type units is that they convert the alternator to battery sensing. If if a boat already has such a system, and a modern alternator, then maybe that's good enough...if not then I'm convinced they are worth £100 and it's not a waste of money...but that's just my opinion...it's not the "truth" /forums/images/graemlins/smile.gif /forums/images/graemlins/smile.gif

 

[Robin2]

Re: You\'re right...

That's a very interesting alternative point of view.

 

[jonjo]

Re: You\'re right...

[ QUOTE ]
If a system does not have split charge diodes (don’t start me on that subject) in it and has a new alternator that charges at 14.2v or above then buying any charge controller is just a waste of cash.

[/ QUOTE ]
It does ( I think ) have a split charge diode, blue vaned block with thick wires going in and out, plus I only have a single master 12 volt switch on a common return negative. That's how Bavaria does it!

There seems to be much vested interest published on the subject. For example before buying an amp hour counting battery monitor I read through the SmartGuage argument that tried to rubbish the amp hour counting method of monitoring battery capacity. Ok so they are correct, amps in does not equal amps out, but it only takes me 3 seconds to reset to 100% after a night on mains power.

 

[jonjo]

Re: Peace brothers.

I was just hoping to distill the high science of the Sterling discussion into simplified advice for the modern AWB owner.

I shall try to arrange for a high pressure system to sit over the Channel between the 14th and 16th of June. Two days on a swinging mooring in Braye Harbor followed by a motor back to the Solent should clarify how my basic alternator setup performs.

Will report back.

 

[Gumpy]

Re: You\'re right...

I have to say that there are a lot of systems out there where the cable between the battery and alternator is just not good enough hence voltage drop at charge currents.
A lot also go to the starter motor then to the start battery and then through a split charge system to the house battery this ads more connections and hence more voltage drop.
Both my alternators go directly to the cabin batteries through just an isolating switch and then in the case of the 12v system on to the starter battery this means that I get about 0.09v drop between alternator and cabin battery ( cable sizes are 50sqmm which is only just enough at 12v) when the systems are charging at 50amps.
Some may call it overkill but I just feel its a better way of doing things.

Julian

 

[Gumpy]

Re: You\'re right...

OK if you have a split charge diode and by the sound of it you have then you will benefit from fitting a sterling.
One point worth noting is that battery capacity degrades with age so you may well start with 100Ah but after a couple of years that will be down to 85Ah when they are fully charged.
This means that if you take out 50Ah from a new 100Ah battery then you are at 50% which is the minimum you should discarge a battery to.
If however you take 50Ah out of a two year old battery with 85Ah capacity you are then down to about 30% capacity or well into the danger zone. The more this happens the worse things get and the quicker the batteries go to the tip.


Julian

 

[jonjo]

Re: You\'re right...

[ QUOTE ]
One point worth noting is that battery capacity degrades with age so you may well start with 100Ah but after a couple of years that will be down to 85Ah when they are fully charged.

[/ QUOTE ]
Indeed good point, I was reminded of this while scanning the SmartGuage info before posting today. I now plan a slow controlled battery drain at say 4 amps to whatever voltage equates to 50% charge, then I can compare consumed amp hours to rated battery capacity and adjust if necessary. Once a season should suffice.

But thinking about this more, the Link-10 could in theory perform such dynamic battery capacity recalibration, better read the manual first.

 

[William_H]

Re: You\'re right...

People put a lot of faith in the % of battery capacity figure given by the amp counting devices. They are accurate in measuring the AH taken out of the battery and hence are a good indication of how you are going in replacing those amp hours but as already suggested the actual % of charge is a variable uncertainty. Mind you I don't think the rule of no less than 50% is all that critical.

As for the claim that ordianry charge system will not charge more than 75% that is totally absurd to me. (unless diodes are fitted)

Any resistance in the charge cables will not reduce the ultimate charge voltage. It does reduce the voltage at the time and at that current which in turn reduces the current into the batteries but as the current reduces the voltage drop reduces so the battery gets fully charged just a little slower. It is no worse than having a lower capacity alternator.

Contrary to many comments the charging system can be very similar in a boat to a car. Especially a power boat used for day trips.
And car systems work very well. (with full battery charge)

It is only when you have a large very discharged service battery and a limited engine running period that the system has short comings.ie you need a smart charger.

I would suggest that if jonjo finds on his trip that he is running the engine for longer than he wants just to recharge batteries then he needs a smart charger regulator. If he is happy to just charge with normal engine use until he returns home to shore power then he doesn't need a smart charger. Certainly the cost can go towards replacement batteries if they are short lived from excessive discharge. olewill

 

[bluedragon]

Re: You\'re right...

[ QUOTE ]

I would suggest that if jonjo finds on his trip that he is running the engine for longer than he wants just to recharge batteries then he needs a smart charger regulator. If he is happy to just charge with normal engine use until he returns home to shore power then he doesn't need a smart charger.

[/ QUOTE ]

That's why I fitted one in the end...good way of putting it.

 

[Chris_Robb]

Firstly, 12.35V is less than 50% charge. I would say that that is the absolute maximum discharge before you start seriously damaging the batteries.

Your charging voltage on engine. I am asuming that you have a split charghing diode, rather than a both 1 or 2 switch. If so, your alternator is probably outputting around 14.2 or so and you are loosing through the diode some .3 or more volts, result is that the voltage seen at the battery is not enough. 13.95 Volts will not charge the battery.

Quite why manufacturers fit this combination of kit is beyond my understanding, as - if you are not on shore power, the charginging facilitoes are NOT fit for purpose. You will really know about it once we get some summer weather and you use the fridge.

Another question: What are your engine batteries - sealed or what - much easier all round if all the same.

DOn't be worried by the long distance sailors worries about float voltages. Your set up will automatically reduce the alternatoirs natural float voltage due to the loss in the splitting diode.

What do you buy? Either sterling or adverc. Adverc are lovely people to deal with and desevre all the business. I am just fitting a sterling - haveing had years oif good service from Adverc (I must be mad!)

If you do fit an advanced regulator, think of installing a NASA BM1 battery monitor. It will tell you what the cumulative in and out is. I have just fitted one, and wish I had done it years ago. You will actually have some idea as to what you are using, - so you will be able to point out to SWIMBO that leaving all the lights on all over the boat will mean at least another 2 hours charging!

 

[jonjo]

[ QUOTE ]
Firstly, 12.35V is less than 50% charge.

[/ QUOTE ]
How can there be so much ambiguity surrounding such a mature science? I followed up on your warning and indeed some voltage/charge graphs agree but a majority indicate 12.35v equates to about 67%. The discrepancy of 67% v. the 77% figure I saw on the Link-10 is probably due to me naively thinking 2 minutes of zero current draw would give a resting voltage. On the internet I am advised variously that between 2 to 6 hours is required to provide a resting voltage.

I feel the purchase of a hydrometer is about to happen, this subject is beginning to interest me.

My engine battery looks like a sealed one (it would take a seriously large Philips screwdriver to undo the inspection caps).

 

[Chris_Robb]

I agree - its extremly confusing! I recently installed a V expensive Electsol battery. It arrived with me reading 12.4V, which I thought was a bit low, so I rang up the manufacturer. In my hands were their guarantee leaflet which says 12.8V fully charged, 12.4 50% 10.3 empty. The guy tells me that at 12.4 its 8-0% charged, so asked why their literature says 50% - he says "are you calling me a liar" Off to good start here I thought, so I said "yes". Hope I never have to use the guarantee.

So what is the truth? I have seen other summaries that say 12.3 is 50%

As one of the others said - If you can always be on shore power every 2 days or so, then stick to what you have got. If not - like us, you are on a mooring, then its really important to sort it out.

 

[bluedragon]

This is the table I use, and of all of them out there seems the most believable according to my observations and SG measurements, is http://jgdarden.com/batteryfaq/SoC.xls

I've actually found it harder to establish state-of-charge with a hydrometer than using the rested open circuit voltage. The SG testers you find in auto shops are OK for Flat/Half-charge/Full, but in-between the scale is squeezed-up too tight to read properly IMHO (anyone know of a good one??)