Charging Dilemma .

[ALLAN WARD]

I need help in solving a charging issue . My system consists of a HEHR 150A alternator , two independant smart regulator systems ( 1 off BALMAR ARS-5 and 1 off NEXT STEP ) and my battery bank consists of 6 off 120ah Lead Crystal batteries .
My dilemma is that even with my battery bank pulled down to 50% SOC , l can only get approx 55amps max from my alternator resulting in hours of engine run-time to fully charge my batteries . Both my smart regulators are giving me almost the same results and l have set them up to suit the higher voltages that Lead Crystal batteries prefer .
My alternator including an identical spare unit have both been bench tested and they produced 140amps each without a problem .

I need to increase the output from my alternator but how ?

Hopefully someone out there has the answer .

Many thanks in anticipation .

[JPA Cate]

First thought is that you are not spinning the alternator fast enough.

Second thought is that there is something suspect in the batteries themselves. i'm not familiar with that chemistry so can't suggest a test; perhaps someone more knowledgeable will chime in.

Cheers,

Jim, on Ann's computer

[Sailmonkey]

The only thing I can think of to test the alt/reg setup would be battery voltage to the regulator terminal....if the alternator produces full current into the batt bank then you have two bad or current limbered regulators. If you don't get the full current from the alt then there is a problem with it.


Sent from my iPhone using Cruisers Sailing Forum

[transmitterdan]

Allan,

What is your battery voltage when the alternator is delivering 55A? How hot is the alternator? Is there a battery temp sensor and it is correctly attached to the battery and regulator? Is there an alternator temp sensor?

There are several possibilities and without data like battery voltage and alternator temperatures we are just guessing. These are in no certain order:

1) Regulator does not supply sufficient field voltage to alternator. You can measure the field voltage with a DC volt meter. If battery is 50% SOC the field should be very close to the battery voltage. If the field voltage is low there can be many causes.

2) The regulator is possibly operating in "belt saver" mode. This reduces the field voltage to reduce the slipping and wear of the fan belt.

3) The regulator senses the alternator and/or battery temperature and reduces the field voltage accordingly.

4) Hot alternators cannot deliver as much current because the wire used in the windings increase in resistance as it heats up. This will cause the current to drop more as the alternator gets hotter. If you temporarily blow a significant amount of air directly on the alternator and the charge current increases then you have possibly found a problem.

5) Alternator is not turning fast enough. Typically to get rated current from an alternator the engine has to turn at >2000 RPMS. This is not a hard and fast rule. If increasing throttle increases the charging current then you may have found a problem.

6) Some battery technology just do not accept high current. I think "lead crystal" is similar to the more commonly known here in the US Valve Regulated Lead Acid (VRLA) or maybe Absorbed Glass Mat (AGM). These batteries typically will accept more than 0.2C so in your case that would be over 150A. But some batteries don't like more than 0.1C. Check your battery data sheet to be sure.

Please don't be offended by this next part as that is not my intention. It is rare that a "stock" small case alternator can deliver its name plate rated current for more than a few minutes. I am not familiar with Hehr except what is available on the internet sites. If this is a small case alternator that sells for $200 USD/Euro and has one or two V belts then it is not going to make 150A for very long if ever. I know alternators are labeled as 150A but that is only when it is very cool (maybe freezing cold) and will not hold that current for very long as it heats up. An alternator that can deliver 150A indefinitely will typically sell for >$700 USD/Euro. Some are listed for a lot more than that and people are happy to pay it.

[Stu Jackson]

Originally Posted by ALLAN WARD

I need help in solving a charging issue . My system consists of a HEHR 150A alternator , two independant smart regulator systems ( 1 off BALMAR ARS-5 and 1 off NEXT STEP ) and my battery bank consists of 6 off 120ah Lead Crystal batteries .
My dilemma is that even with my battery bank pulled down to 50% SOC , l can only get approx 55amps max from my alternator

One engine & two alternators with separate regulators?

What monitoring system are you using? What engine rpm?

What is the voltage at the bank(s) when charging?

[smac999]

I don't understand your 2 regulators. you have 2 on board and have tried both separately with same result? or you actually have 2 hooked up at same time to one alt??



you can test the alt by running 12v direct to the field input bypassing the regulator. (disconnect reg field to alt) if you get lots of current then your probably have a regulator or reg wiring issue. don't do this for very long as the alt won't have control to stop overcharging.


if you still don't get amps. then your probbaly have an alt or alt wiring issue. what size alt wire are you running and how long is it? what is your voltage at the alt post and at the battery while running? you probably need 1/o or 2/0 wire for the alt. is it going through a diode battery isolator?


also where are you measuring the 50a? on a battery monitor? this is a net into the battery. and your alt is putting more out. you'd have to subtract the loads to know alt output. or are you measuring with a clamp meter on alt cable?

[ALLAN WARD]

First of all to everyone , many thanks for your response so far and l really appreciate your advice .
Last season while cruising in Brazil , after contacting the supplier of my new Lead Crystal batteries and following their recommendations regarding the settings of both my regulators , l became convinced that the culprits had to be my two recently overhauled 150amp alts , so when returning to South Africa for a short break l lugged both alts off for bench testing . According to the repairers both alts are 100% so it is back to square one .

Regarding some of your questions , l have two separate smart regulator systems but only one is in use at a time . In other words one is a spare ready for use with the flick of a switch . The same for my alts , one is a spare unit although l swopped them over to test each one .

At the time when l built my boat l was pedantic about the pulley sizing and with the maximum permissible revs of the alt being 10000rpm and the engines max revs being 3000rpm l settled at 3 : 1 . Although when motoring l usually run the engine at 1800rpm giving me 5400rpm at the alt , while at anchor l run the engine at approx 1500rpm .

I am using my battery monitor as a reference but now l understand that it would be nett of the load on the batteries at the time , although the output is so low l can't imagine that the fridge/freezer would have any significant effect on what the alternator should be producing .

I don't have a diode battery isolator as my house batteries are charged by the Hehr , while my start battery is charged by the 70amp engine alternator . I do have a master switch which allows switching to different combinations .

The NEXT STEP regulator incorporates a battery temp sensor but l dont have an alternator temp sensor . I would like to think that l have done the best for keeping the alt cool in that l have a blower sucking all the hot air out of the engine room in an attempt to keep the ambient temp down . Secondly , the Balmar reg is set-up without any belt load management to increase output .

Regarding the cable run of approx. 3m from the alt , 99% of the run is 50mm(sq) with two very short 16mm(sq ) tails that connect from a cable clamp to the alt . l did this so that the smaller cable could handle the engine vibration better.

transmitterdan , you have given me a lot of great info increasing my understanding of how these systems work .

As far as all your questions regarding voltage and current readings , my wife and l return to Brazil at the end of the month to our beloved boat which is where my notes are with all my tests .

From your replies l will make notes of the various tests that l need to conduct and if you can assist me with any other tests l can make to try and resolve this issue , that would be really appreciated .

[ALLAN WARD]

Something l forgot to mention is that l am now thanks to transmitterdan also aware that possibly it might have something to do with the characteristics of Lead Crystal technology .

I will read the spec sheet and check up on that , thank you .

[ricorrea2002]

Hi Allan,
Unfortunately I don't have the answer. More over I have the same question.

I have 3 AGM of 210Amps (630 amps), Gen and Solar Pannels.

My GEN is 4KW. When my batteries are low (12,3 v) en bulk or charge only draws 50 amps max. IT SHOULD BE above 100 amps

The Gen is not the problem, when I run the engine (Alternator of 130 amps) the same quantity of amps are draw.

I think the temperature sensors in the batteries are nor a problem, because from the begining the amps are limited no more than 50.

I have LINK 2000 monitor, I think it is not the problem

So, my guessing is the batteries itself limit the load even in charging or bulk step.

By the way, I got better result loading the GEN with 110 lamps (8 x 200 Watts)

[DeepFrz]

Allan, for one thing your cables from the alternator are to small. If you look at the wire size calculator here: DC Cable Sizing Tool - Wire Size Calculator - MM2 & AWG - solar-wind.co.uk

you find that for a 6 m cable length (3 m there 3 m back) for a 3% drop at 14.4 volts and 120 amps you should be using 70mm sq. cable. The short run of 16mm sq. cable could be a problem depending on where your sense wire comes from. I used 14.4 volts because I don't know what voltage is recommended for Lead Crystal batteries.

Granted that you will not always be putting out 120 amps but your alternator should be capable of that. That means that the short section of 16mm sq. cable is greatly undersized. You should at least replace the short sections of 16mm sq. cable with matching 50mm sq. cable. You are still probably adding to your charge time by having excessive voltage drop on the 50mm sq. cable but you will need to measure that yourself and that shouldn't be a problem if your sense wire comes directly from the battery + terminal.

It is recommended that a 150 amp alternator be adjusted by the regulator to about 120 amp max output to keep it running below its max temperature. Do you have an IR temp sensor? They come in very handy for checking alternators, engines, cable connections, etc. That and a clamp on amp meter and accurate digital voltmeter will help you troubleshoot the problem. I can't see you toolbox so I just thought I would mention that.

[ErikFinn]

Originally Posted by DeepFrz

Allan, for one thing your cables from the alternator are to small. If you look at the wire size calculator here: DC Cable Sizing Tool - Wire Size Calculator - MM2 & AWG - solar-wind.co.uk

Just wanted to thank you for the great link!

[sailinglegend]

Originally Posted by ErikFinn

Just wanted to thank you for the great link!

Beware this calculator doesn't use there and back distance just the single length from load to battery. Many of these calculators are like this, but they don't tell you exactly what "distance" they require. This chart will give you a cable size that is twice as large as you need - maybe not a bad thing - but a huge extra cost, and profit for the manufacturers as most of these sites sell or make the cables.

Most chart-based calculators use there and back as the distance for their calculations.

Try this one:

Circuit Wizard - Blue Sea Systems

[hellosailor]

From www.leadcrystalbatteries.com, apparently the Chinese sole source of the world's greatest new battery technology:


" A unique micro-porous high absorbent mat (AGM), high-purity lead calcium selenium
plates, safe SiO2 electrolyte solution that solidifies into a white crystalline powder when
charged/discharged."


Plenty of information on discharge rates but less on charge limitations. Beats me how a solid crystalline powder could work as an electrolyte, but, they say it does.

[DeepFrz]

In the Blue Seas calculator it comes down to 42.5 mm2 at 120 amps (AWG 1). 21.2 mm2 (AWG 4) if you aren't worried about the 3% voltage drop. The voltage drop of course will decrease as the current decreases as the batteries charge. However if you want an efficient charging system you would be wise to stay with the 50 mm2 all the way to the alternator.

hellosailor, that's interesting about not much info on charging rates. I know that these batteries were hyped up pretty good a few yrs. ago and then seemed to drop out of sight.

Although I did come up with this on the manufacturer's website.

Charges up to two times faster than conventional alternatives. Excellent high-current discharge ability.

[DeepFrz]

Ooops. At least one manufacturer uses a 3 hr. rate instead of the 20 hr. rate of deep cycle batteries.

Allan, what make and model battery do you have? Do you have a link to the manufacturer website? It might help us understand what is going on.