pauldowrick
Member
I am looking to replace my alternator for a higher amperage version.
Is the Balmar, smart alternator worth the extra money?
Is the Balmar, smart alternator worth the extra money?
Are Balmar alternators worth the money?
- Thread starter pauldowrick
- Start date
geem
Well-known member
Are you sure you need one? If you are charging lead batteries, they don't spend much time at full output before they drop off their charge output.
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Yes, very worthwhile. Must be partnered with a decent regulator and be aware that you might need to upgrade the drive belt to carry the load - off the shelf serpentine belt kits are readily available.
Tranona
Well-known member
Depends on what you are replacing and why you think you need a higher output. Usually fitted because the battery bank has been increased or you are changing to lithium so your charge acceptance is greater than the output of your current alternator.
Mistroma
Well-known member
I'd agree that it's difficult to say that it's worth getting a Balmar without more detail.
I bought a 110A Balmar alternator about 12 years ago when leaving UK for an extended cruise. I wanted a spare and intended to swap over the standard 80A alternator en-route. I never bothered swapping them over as solar was becoming ever cheaper.
Don't look at one thing in isolation and consider lots of things. e.g.
- Usage profile
- Average daily hours under engine
- Available solar/wind generation
- Battery chemistry and capacity
- Type of alternator regulator already fitted
- etc.
The standard 80A alternator normally sat at 30-40A initially and then fell back to lower levels fairly quickly. A better regulator would speed up charging but I wouldn't get much benefit from charging rates above 50-60A as my normal engine run times were usually quite long. Obviously useful if I needed to run the engine at anchor. Not so much when solar is providing a lot of power.
However, I would come to a different solution with Li-ion batteries or need to charge at anchor or greater power needs and so on.
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geem
Well-known member
Converting to lithium and expecting to charge with the alternator is not straight forward or cheap. The difficulty is when the battery has a High Voltage Event (HVE), the BMS will shut down the battery to preserve the cells. This will usually blow the alternator diodes. To have an external reg communicating with a lithium battery BMS is complex and expensive. These BMS will shut down the alternator before isolating the battery, but you need a deep wallet.
Mosfet based lithium batteries are better charged with a DC/DC charger from the engine battery. For this, a high output alternator makes more sense, but the cheaper way to do it is fit an oversized standard type alternator and just charge the lithium through a DC/DC charger at 50% of the alternator rated output. Thr new Victron DC/DC charger is fully programmable up to 50A output.
I cant ever see the need for the Balmar alternator.
B27
Well-known member
If you want to put a lot of charge into the batteries quickly, a smart alternator could be a good way forwards.
But as others have said, I'd would look at the system as a whole, together with anticipated use patterns.
Likely engine hours, battery bank sizes, big loads etc
Also whether you have splitter diodes, VSR or what?
I think Lithium FEPO4 batteries will be the common option for certain sizes of boat within a few years, so I'd be looking for a solution which is compatible with that.
But as others have said, I'd would look at the system as a whole, together with anticipated use patterns.
Likely engine hours, battery bank sizes, big loads etc
Also whether you have splitter diodes, VSR or what?
I think Lithium FEPO4 batteries will be the common option for certain sizes of boat within a few years, so I'd be looking for a solution which is compatible with that.
geem
Well-known member
Unless you have a large battery bank, there is little to be gained from a high output alternator. If a battery is very discharged then the alternator will put in a lot of amps but with lead, you shouldn't be discharging past 50%.
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I take a different view to the posters above. I have a 750ah AGM bank. Our usage pattern is generally 48hrs or so at anchor (with solar) then short periods of motoring, otherwise under sail. I fitted a Balmar alternator and regulator because when the engine is running I need high output for fast as possible replenishment of the partially depleted bank. The old Hitachi alternator with internal regulator really made next to no impact on bank replenishment as output would quickly fall off as V increased. The Balmar upgrade has made a significant difference, producing high output even at engine low speed and maintaining a high level of output. I’d never attempt to fully recharge from the engine alternator and would abide by Calder’s 80% charge rule were I to use the engine alternator whilst at anchor to charge, however that has never been needed yet as solar provides adequate charging until I'm either motoring or have shorepower. The Victron AGMs that I have can be cycled below 50% SoC though I have never yet needed to do so. I maintain that the Balmar upgrade has been very worthwhile.
geem
Well-known member
Part of that may have been a poor original alternator. Most stock alternators these days are very capable without resorting to an over priced balmar set up.
Before !lithium and much solar, we used to have a 500Ah 24v house bank(1000Ah at 12v equivalent) and the bog standard 60A alternator at 24v. I used to monitor the amps on the panel meter. The alternator was limited by the Voltage set point such thst we rarely saw more than 30A even on batteries a bit depleted. After 10 minutes of running we would be under 20A and at 14v. A bigger alternator would have made no difference 10 minutes into the charging cycle.
Tranona
Well-known member
Not many people have a 750ah bank - and the OP does not give enough information to even hazard a guess whether a Balmar is worth the extra money. Maybe he will come back and explain what he is trying to achieve.
B27
Well-known member
A modern automotive alternator will charge a 100Ah battery at 50 A or more, so you don't need a terribly big bank to make good use of a high output alternator.
With a boat, where engine running may be many hours at a time, a smart control of some sort is desirable, if good battery life is to be achieved. A smart alternator will use charge voltages of 14.4V or even significantly more, but will reduce that when it senses the batteries are close to charged.
A dumb alternator on a marine or plant engine intended for extended continuous running will likely be regulated to slightly lower voltage, which significantly reduces current.
'Small' voltage drops of the order of a hundred mA make a big difference in current into the battery, so a smart, battery sensing alternator can often achieve a big improvement over a dumb machine-sensed alternator
The gain from a smart alternator varies with the engine running scenario, if you want to cram in a good amount of charge with an hour's mooring in the morning, leaving the solar to top up, there may be gains to be had.
A dumb alternator from a car, which will probably be fairly powerful and regulated at 14.4V (or a bit more) might be a good compromise for many yachts, but could result in excessive gassing on a boat which motors for days on end.
Being able to tweak the charge curves to suit variants of 'Lead Acid' battery might be a gain.
Another gain might be 'soft start' control, a big dumb alternator can be cruel to drive belts and even stall small engines or prevent them starting.
It would be more useful to look at it numerically, with the parameters a particular user has in mind.
Vague catch-all statements don't help much.
Also bear in mind the effect of big loads like thrusters, windlasses, inverters.
Looking forwards, everyone engine-charging LifePO4 house banks and Lead-acid starting batteries will need some complication, I expect we'll see more solutions to that on the market soon. The days of big lead house banks are generally numbered IMHO. I don't think I'd be investing a lot in a lead-specific alternator, I don't know what Balmar are offering for mixed or lithium systems.
With a boat, where engine running may be many hours at a time, a smart control of some sort is desirable, if good battery life is to be achieved. A smart alternator will use charge voltages of 14.4V or even significantly more, but will reduce that when it senses the batteries are close to charged.
A dumb alternator on a marine or plant engine intended for extended continuous running will likely be regulated to slightly lower voltage, which significantly reduces current.
'Small' voltage drops of the order of a hundred mA make a big difference in current into the battery, so a smart, battery sensing alternator can often achieve a big improvement over a dumb machine-sensed alternator
The gain from a smart alternator varies with the engine running scenario, if you want to cram in a good amount of charge with an hour's mooring in the morning, leaving the solar to top up, there may be gains to be had.
A dumb alternator from a car, which will probably be fairly powerful and regulated at 14.4V (or a bit more) might be a good compromise for many yachts, but could result in excessive gassing on a boat which motors for days on end.
Being able to tweak the charge curves to suit variants of 'Lead Acid' battery might be a gain.
Another gain might be 'soft start' control, a big dumb alternator can be cruel to drive belts and even stall small engines or prevent them starting.
It would be more useful to look at it numerically, with the parameters a particular user has in mind.
Vague catch-all statements don't help much.
Also bear in mind the effect of big loads like thrusters, windlasses, inverters.
Looking forwards, everyone engine-charging LifePO4 house banks and Lead-acid starting batteries will need some complication, I expect we'll see more solutions to that on the market soon. The days of big lead house banks are generally numbered IMHO. I don't think I'd be investing a lot in a lead-specific alternator, I don't know what Balmar are offering for mixed or lithium systems.
geem
Well-known member
Balmars offering for lithium are not the best. Wakespeed seem to be the favoured external regulator for lithium. Another new player entering the market is Zeus.
I have a large frame 155A 24v alternator that I haven't yet got around to fitting. I am trying to decide if its worth it for charging my lithium with the added complexity of control that is needed between alternator and bms. I may sit on the fence for a while and see what develops
For now 920w of solar, 1.1m diameter wind turbine, towed turbine, diesel genset with 115A of charging capacity at 24v and 30A off the engine dc/dc via a bog standard 60A alternator does us fine.
Porthandbuoy
Well-known member
Sheolin came with a 110A Balmar alternator and controller. Batteries are 2x110Ah sealed lead acid domestic and 1x110Ah engine start. There is a dumb split charging system, basically just a sealed block of Schottky diodes.
When the engine starts there is a 2 minute delay before the Balmar alternator delivers any current, presumably to let the engine warm up.
Max current I’ve ever seen it deliver was 30A into the batteries, and that tailed off very quickly.
I’ve not recorded the amps while retrieving the anchor using the 1000W Lofrans Cayman windlass, but I can’t see the Balmar being any better than a conventional alternator.
I had to replace the alternator belt with a top of the range cogged belt as it ate conventional ones. Last year I didn’t even have to adjust it.
Is a Balmar alternator worth the money? I’d say no. Not in a relatively simple setup like mine. I’ve never discharged my batteries below 85%, solar keeps pace with demand (if the sun shines).
If there is a plus it’s the Balmar controller drops the charge voltage to 13.4v when it senses the battery is full, I.e. accepting very little current. Does that help? Car batteries sit at 14.4v all the time (well, mine does) and last for years.
If you regularly take your batteries into deep discharge territory, have a large battery bank, or lithium batteries capable of accepting a high amperage then fitting a Balmar alternator could help, but only as part of a well considered whole.
When the engine starts there is a 2 minute delay before the Balmar alternator delivers any current, presumably to let the engine warm up.
Max current I’ve ever seen it deliver was 30A into the batteries, and that tailed off very quickly.
I’ve not recorded the amps while retrieving the anchor using the 1000W Lofrans Cayman windlass, but I can’t see the Balmar being any better than a conventional alternator.
I had to replace the alternator belt with a top of the range cogged belt as it ate conventional ones. Last year I didn’t even have to adjust it.
Is a Balmar alternator worth the money? I’d say no. Not in a relatively simple setup like mine. I’ve never discharged my batteries below 85%, solar keeps pace with demand (if the sun shines).
If there is a plus it’s the Balmar controller drops the charge voltage to 13.4v when it senses the battery is full, I.e. accepting very little current. Does that help? Car batteries sit at 14.4v all the time (well, mine does) and last for years.
If you regularly take your batteries into deep discharge territory, have a large battery bank, or lithium batteries capable of accepting a high amperage then fitting a Balmar alternator could help, but only as part of a well considered whole.
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I agree with a lot of that, a large alternator in an otherwise "standard" environment is never going to be much good, be like fitting a 250hp turbo diesel in my K reg Escort 1.1 which I had in '79.
Trying to power a Balmar alternator on a standard belt is folly. Fit a serpentine belt. The fact that it shreds standard belts is evidence that it is producing a lot of power output, it won't shred belts if its only producing 10A.
When I fire up our engine after we've been laying to anchor for a couple of days I'll typically see in excess of 70A from our 70A Balmar alternator. Yes, it produces more than its rated output whilst it is cold. The power curves show that when on the test bench it produced over 100A. Once it warms the output reduces but it will maintain well in excess of 50A for a sustained period, indeed it's normally at about that level when I shut it down and get under sail.
I suspect that like so many systems the Balmar only optimises in a well designed and implemented coherent system.
Tradewinds
Well-known member
I was under the impression that Balmar alternators gave much more output at lower revs typically for those cruisers charging at anchor. Of course this impression was formed pre stone age when solar was less universal and lithium was just a twinkle in someone’s eye.
Could never afford one anyway.
Could never afford one anyway.
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They do, mine will produce 50A ish at tickover no trouble. But I don't use the main engine to charge whilst at anchor - as well as being an environmental disaster it's also not good for the engine, especially our 75hp turbo Yanmar.
