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NAGG
28-01-2012, 12:49 PM
Hi All

I'm just curious to know if anyone is using a VSR to charge their leccy battery (direct from the outboard motor)

Are there any issues ? - particularly running cable from the transom to the bow :-?

interested to hear your comments

Chris

Kondo 1
28-01-2012, 04:20 PM
Hi Nagg,

I do run a system similar although it is reasonably complex as my objectives were slightly different and the addition of charging whilst underway is a welcome benefit. I have 3 batteries in the Tinny, start, house and electric, and the first 2 are controlled by a BEP VSR cluster - the third is managed by a CTEK 250 Dual and Smartpass.

The reason I went this way was I was wanting to ensure I could charge the electric motor battery quickly whilst away very quickly after a full days fishing, the smartpass and the Dual do this very effectively and additionally once the electric motor battery is charged either via the outboard, car or the fixed Ctek charger it then tops up and maintains the start and house as well. Its all automatic and works wonderfully so its always being used and my batteries are always 100%, something I am absolutely anal about given my boat gets used in remote areas.

Overall I dont reckon I get more than 10 amps going forward whilst underway which probably does barely more than top up if I am using the electric in short bursts the principle reasons I went through this set up have been achieved so I am happy all round.

Depending on the outboard and battery setup I would suggest some nice fat cables running off a VSR would likely do the same job, albeit simpler.This is of course if you were principally trying to charge whilst underway only. One proviso would be that the batteries would need to be similar chemistry in this paralleling setup - I have read all types of things in the past etc etc, but in my personal experience mixing an AGM and a calcium battery in a setup like this will shorten the lives of both and give very poor results. Whilst my experience was in was in my landcruiser, the principles remain the same.

Personally I wouldn't probably bother if my outboard's alternator provided less than 20 odd amps at least and the existing batteries were of similar chemistry, however it can certainly be done.

Callop
28-01-2012, 04:25 PM
Hi chris,

There are probably only 4 things to worry about.
1. does the engines alternator produce enough amps? Shouldn't be a problem with your new rig.
2. Voltage drop from transom to bow? not a problem if the correct size cable is used.
3. do it yourself or professional ? I got a car sparky who does a bit of boat work on the side to do mine. Tinned cable, anderson plugs, heat shrink, etc.
4. Keep in mind that the alternator only supplies bulk charge. You still need to use a multi-stage charger after a trip to maintain maximum battery life. desulphation etc
Wouldn't be without it now.
Dave

NAGG
28-01-2012, 05:54 PM
Hi Nagg,

I do run a system similar although it is reasonably complex as my objectives were slightly different and the addition of charging whilst underway is a welcome benefit. I have 3 batteries in the Tinny, start, house and electric, and the first 2 are controlled by a BEP VSR cluster - the third is managed by a CTEK 250 Dual and Smartpass.

The reason I went this way was I was wanting to ensure I could charge the electric motor battery quickly whilst away very quickly after a full days fishing, the smartpass and the Dual do this very effectively and additionally once the electric motor battery is charged either via the outboard, car or the fixed Ctek charger it then tops up and maintains the start and house as well. Its all automatic and works wonderfully so its always being used and my batteries are always 100%, something I am absolutely anal about given my boat gets used in remote areas.

Overall I dont reckon I get more than 10 amps going forward whilst underway which probably does barely more than top up if I am using the electric in short bursts the principle reasons I went through this set up have been achieved so I am happy all round.

Depending on the outboard and battery setup I would suggest some nice fat cables running off a VSR would likely do the same job, albeit simpler.This is of course if you were principally trying to charge whilst underway only. One proviso would be that the batteries would need to be similar chemistry in this paralleling setup - I have read all types of things in the past etc etc, but in my personal experience mixing an AGM and a calcium battery in a setup like this will shorten the lives of both and give very poor results. Whilst my experience was in was in my landcruiser, the principles remain the same.

Personally I wouldn't probably bother if my outboard's alternator provided less than 20 odd amps at least and the existing batteries were of similar chemistry, however it can certainly be done.

Thanks for the reply Kondo ....... Certainly things to consider !

I will be running a lead acid cranking battery & a 200 amp AGM Deep cycle for the leccy - I was just hoping to use the motors alternator -- to top up the leccy battery when traveling I think the output on the F70 is about 16 amp ....... It sounds simple but maybe not !

Chris

Kondo 1
28-01-2012, 06:00 PM
Thanks for the reply Kondo ....... Certainly things to consider !

I will be running a lead acid cranking battery & a 200 amp AGM Deep cycle for the leccy - I was just hoping to use the motors alternator -- to top up the leccy battery when traveling I think the output on the F70 is about 16 amp ....... It sounds simple but maybe not !

Chris

Hi Mate,

You are dead right on the F70 - I have one too and I reckon lucky to see 10 amps tops at the front (Getting a clamp meter shortly). ANd I think with a 200 amp battery the alternator will truly struggle... In fact they reccommend for proper 2 stage chargers they are at least 10% of the rated amp hour capacity (I always go much bigger - I have a 25 in the boat but have a bushpower 50+amp unti which is bloody brilliant)

Just make sure the Lead acid is true lead acid - those sea master golds that allot of people have are calcium and will truly upset the charge profile.

Let me know how you get on :)

NAGG
28-01-2012, 06:01 PM
Hi chris,

There are probably only 4 things to worry about.
1. does the engines alternator produce enough amps? Shouldn't be a problem with your new rig.
2. Voltage drop from transom to bow? not a problem if the correct size cable is used.
3. do it yourself or professional ? I got a car sparky who does a bit of boat work on the side to do mine. Tinned cable, anderson plugs, heat shrink, etc.
4. Keep in mind that the alternator only supplies bulk charge. You still need to use a multi-stage charger after a trip to maintain maximum battery life. desulphation etc
Wouldn't be without it now.
Dave

So you have done it Dave ..... ?

I do understand about the bulk charge ........ It's got to be better than none - even if it is in conjunction with a switch.
It would be handy when you are saying fishing offshore on Spot lock casting or jigging - then you have an hour run back to camp / ramp ......... It certainly would be handy.
If I do this ...... I will have it done during the building of the the boat when all the wiring is done

Thanks for the input Dave

Chris

albey
30-01-2012, 06:38 PM
Gday Nagg,a couple of things will create problems for you here.
1.Charging a battery under ideal conditions require that you charge at a 10 hr rate,can be done faster with more current availablemor slower if you have insufficient current,so basically for a 200A battery you would need an available 20A and THEN charge for 10 hrs to bring the battery up to full charge,obviously this is not practical,I'm talking here of starting with a dead flat battery which is fairly normal with leccy bats,so the most you are going to do is top up,not the ideal way to go for battery longevity.
2,Most VSRs dont switch the charge from the start batteryto backup battery but rather when the start battery is full the VSR brings in the backup battery in parallel,this is not a good idea for the start battery because if the back up battery is dead flat or even way down,the the alternator will try to supply max current and this could cause the fully charged start battery to boil,particularly if running for an extended period.
So as has already been suggested use the biggest leccy battery you can afford and at the end of the day whach the CTec or whatever on for the night.
Boating is such fun

Kondo 1
30-01-2012, 07:10 PM
You reminded me of one important point Albey.

If you have a severely discharged large battery up front with a low powered alternator and a VSR the VSR will chatter and depending upon the internal resistance and rate of charge of the big battery you "can" discharge your smaller battery down back quicker than it can be charged by the alternator...

It all depends on the charge acceptance of the large battery, current capacity of the cables and the VSR. I think the BEP VSR's are set quite high so it shouldn't be a massive problem but I have had this issue in my landcruiser (charge issues + fridge + severely discharged second battery = Starting issues) - however my issues were probably compounded by a few factors, however I would keep it in mind, especially with the F70 where a rope start is a PAIN :).

Some batteries like the Lifeline, Deka's and Optima's have a charge acceptance on 100 odd amp hour batteries of 80-100 amps sub 75% SOC so they can really rip capacity out of another charged battery in parallel very quickly IF the wiring is up to it.

I haven't had an Issue on my similar setup but my Eleccy battery is twice removed from the start battery through 2 seperate VSR's and a virtual VSR in the CTEK Dual and I have not had any issues whatsoever... May not be an issue but I thought it would be worthwhile mentioning.

albey
30-01-2012, 07:41 PM
A couple of fair points here Kondo,though just remember that a VSR does not isolate the start battery when it brings another battery into circuit,but as already mentioned just parallels it,also my experience with VSR chatter is normally caused by siting the VSR too far from the start battery and so incurring some inbuilt voltage drops depending on cable size.The BEP unit is priced well and that is why it sells well but it not the best unit around by a long shot due to the fact that its cut in voltage is set too high and is not adjustable.There are others in the 4WD industry more suitable though are more $.
With your set up,I guess you get away with it because you consciously charge your batteries via CTek at the end of the day,I dont think however that the O/B alternator is doing too much,they are just not big enough to cope with high capacity flat batteries,considering the amount of time that they are given to charge.
You are dead right by the way regarding putting a discharged battery across a full one with insufficient charge input,you will effectively discharge the full battery and for sure this will cause chatter also.

Steve B
30-01-2012, 08:06 PM
Chris,,

Waist of money unless your doing 2 hour + straight trips in your boat. I had one on my frenzy...It actually charged a 24v setup (well I thought it would) for my electric motor...charging one then the other in 60 sec intervals back and forward... The 90 Opti had a 70amp alternator I think...and it still barely put anything into the front batteries..even after running up and down Mondy like I used to....the thing cost about $300 to install. Better off with a good inbuilt charger for your boat so you can just plug in when you get to power.

Cheers Stevo

Kondo 1
30-01-2012, 08:11 PM
Gday Albey,

Very fair points for sure, I guess my application and main goals when setting this system up was to absolutely maintain the charge and integrity of the start battery as the foremost importance (mostly becasue I do travel remotely and the F70 needs a terminal volatage of I think at least 9 volts to even pull start - for the ECU). And secondly maintain good power to house and distant third the Electric motor battery. However when travelling remotely in previous boats I have had trouble being able to charge quickly and easily the trolling battery and I guess to a smaller extent house (mainly due to the fact I have had 2 strokes in the past and allot less safety and electronic gizmos on previous boats). The system I have does achieve what I set out for very well and indeed provides a few side benefits, most of all when charging off the vehicle I get a true 3 stage charge into the trolling battery and importantly top up the house and start if required and secondly it does allow charging from the motor whilst underway to the batteries in order of their importance to me. In my experience the motor does a sterling job on the first 2 batteries and possibly provides a minor (if maybe almost indiscernable) charge to the front battery which whilst not necessarily desired certainly does no harm in my setup. Overall very happy but honestly I would not have have gone through the exercise and expense to solely charge the front battery whilst underway.

Have to agree on the BEP stuff, I dont mind it and have actually used a motorised VSR switch in one of my cruisers effectively (albeit once I fixed my charge issues with a 270amp alternator :)) and I probably in the end appreciated the higher cut-in as my primary goal is alway to keep the start battery in top shape. However (long story) I did swap out the BEP switch for a new baintech VSR in both my 100 and 80 series cruisers for a new baintech unit a few weeks back. Time will tell but so far very happy, resin encased solid state MOSFET controlled and economically priced. Would seem like it should remain reliable for the longer term given its construction unlike a few redarc untits I have used (these were earlier untis and I understand the newer ones are much much better). In fact given its contruction it would probably work quite nicely in a boat too, however I do like the neatness of the BEP clusters, and so far have suited my needs.

I probably go a bit overboard with my wiring and redundant systems however a career in aviation will do that to you :)

Honestly never had the issue with chatter dueto distance and voltage drop as I have always gone with overkill wiring I have always used and really only had the chatter issue with underpowered/troubled alternators usually at idle or low speed with severely discharged batteries (however this experience could be applied to a small output alternator such as the F70) - however some smarter VSR's now try and alleviate the issue with electronics witholding the cut-in for up to 15 seconds and holding it under the cutout voltage as well which in my opinion is nice BUT in an underserviced charging system would likely add additional strain to the priority battery in a simple VSR controlled parallelled charging system...

What VSR units have you had good experience with? ALways keen to look at new things :)

albey
30-01-2012, 08:56 PM
Well thought out Kondo.
Of all the units Ive fitted Id say 80% would be BEP due mainly to the mounted appearance and definately cost,as youve already experienced a better unit though not as attractive and would account for another 15% are the Bainbridge units,Ive fitted a few others which were not sourced by me so brands are not remembered even in my Navara I have a unit thats been there now for 6-7 years and given no problems whatever,but was a bitch to install,more than 3 wires,has an external relay etc but does have a pushbutton override,Brand--???? sourced from 4wd supplier,Ill have a look in the daylight.My personal choice Baintech.
I agree that a 270A alternator will cure most problems,though you probably need a 4WD to carry it. and also agree that the cause of a lot of electrical problems are caused by cable that is too light.I do tend to overkill on any of my installations but to date have not experienced any problems caused by under rated cable.
I dont do a whole lot of work on O/B electrics so outboard experience is limited.The vast majority of my electric/electronic work is on diesel inboards or Mercruisers and apart from my own, absolutely none on cars and trucks.By the by in my truck I also carry a 60W solar which I put on the top and plug in if Im camping for a few days or more to help the Waeco battery.A seven week trip around Qld and a 4 month trip around Australia and so far has worked like a charm.

NAGG
30-01-2012, 09:00 PM
Chris,,

Waist of money unless your doing 2 hour + straight trips in your boat. I had one on my frenzy...It actually charged a 24v setup (well I thought it would) for my electric motor...charging one then the other in 60 sec intervals back and forward... The 90 Opti had a 70amp alternator I think...and it still barely put anything into the front batteries..even after running up and down Mondy like I used to....the thing cost about $300 to install. Better off with a good inbuilt charger for your boat so you can just plug in when you get to power.

Cheers Stevo

thanks Steve ..... I wont bother with an onboard again ........ just use my 25amp ctek & use it with 240 vlt or the gennie
My onboard minn kota charger died from the salt

chris

NAGG
30-01-2012, 09:04 PM
Gday Nagg,a couple of things will create problems for you here.
1.Charging a battery under ideal conditions require that you charge at a 10 hr rate,can be done faster with more current availablemor slower if you have insufficient current,so basically for a 200A battery you would need an available 20A and THEN charge for 10 hrs to bring the battery up to full charge,obviously this is not practical,I'm talking here of starting with a dead flat battery which is fairly normal with leccy bats,so the most you are going to do is top up,not the ideal way to go for battery longevity.
2,Most VSRs dont switch the charge from the start batteryto backup battery but rather when the start battery is full the VSR brings in the backup battery in parallel,this is not a good idea for the start battery because if the back up battery is dead flat or even way down,the the alternator will try to supply max current and this could cause the fully charged start battery to boil,particularly if running for an extended period.
So as has already been suggested use the biggest leccy battery you can afford and at the end of the day whach the CTec or whatever on for the night.
Boating is such fun

I knew you guys would be a world of info ....... I might just stick with a charge at the end of the day via my 25amp C tek & 240 volt or the gennie.

many thanks

chris