Alternators and Regulators

Malabarista said:
So the internal regulator in the alternator will gradually decrease its output and possibly damage a large battery bank by undercharging?
Or is this guff from a guy trying to sell me a Balmar?
Click to expand...

Your alternator is new, you have 650w? of solar power, i'd say a Balmar is a waste of money.

Old saying, "he who dies with the most toys wins".....................................That's bollox ;)
 
Malabarista said:
So the internal regulator in the alternator will gradually decrease its output and possibly damage a large battery bank by undercharging?
Or is this guff from a guy trying to sell me a Balmar?
Click to expand...
The regulator regulates maximum voltage only, to limit the voltage it cuts back on the amps, so once it reaches max voltage your amps output will fall. The A to B unit can boost charge voltage, but you get less amps out than than the alternator is producing. If say you were charging at 14.4 volt @ 60 amp, if you carried on the voltage would increase due to the battery internal resistance increasing as the charge level increases. So in limiting voltage the alternator cuts back amps, and as the voltage does not rise, the charge amps the battery takes also falls, so you see the all fall in amps. Nothing you can do, only increase regulator voltage, but once the new voltage is reached, the same happens again.

Brian
 
halcyon said:
The regulator regulates maximum voltage only, to limit the voltage it cuts back on the amps ...
Click to expand...

That has to be the most bass ackwards explanation of how a constant voltage alternator works ever. The alternator does not "cut back on the amps" .. it simply produces a constant output voltage, and the amps are simply whatever the battery will pull at that particular voltage (up to the maximum output current of the altnerator). The alternator's control circuit has no knowledge of the output current and does not use it in it's feedback circuit, it simply drives the field coil to try and achieve the pre-set output voltage, and thats all.
 
I am glad this came up. about to start a rewire and any information is useful.

Here is another question. I am considering moving to AGM batteries should I change the regulator on my alternator to charge at a higher voltage?
 
Sandy said:
I am glad this came up. about to start a rewire and any information is useful.

Here is another question. I am considering moving to AGM batteries should I change the regulator on my alternator to charge at a higher voltage?
Click to expand...
What voltage does it charge at now?
How reliant on the alternator are you for charging?
How much do you run your engine?
How much do you draw from the batteries when the engine's not running?
Do you have cash burning a hole in your pocket?
 
PaulRainbow said:
Your alternator is new, you have 650w? of solar power, i'd say a Balmar is a waste of money.

Old saying, "he who dies with the most toys wins".....................................That's bollox ;)
[/
?Good morning
I wasn’t planning on buying a Balmar ( Balkan? or otherwise). I was studying/ researching how to address the problem of my rather large house bank. I read in the link provided that the alternator would self regulate downwards as it got hotter and it is a problem in that with a large bank it can leave them chronically undercharged in the absence of sufficient sunlight. This was why i had thought to use the A-B to help keep the volts ( and thus the amps ) above what the internal regulator allows. Please excuse me if i am being hard of thinking again.
On another tack would directing the engine air intake ( with a short length of heat resistant ducting) to just above the alternator have any noticeable impact? Anyone done it?
PS yes i am very bored with crimping battery cables
Click to expand...
 
Sandy said:
I am glad this came up. about to start a rewire and any information is useful.

Here is another question. I am considering moving to AGM batteries should I change the regulator on my alternator to charge at a higher voltage?
Click to expand...
Well apparently i have an A-B charger redundancy ? if you want to go that route. It owes me about £70
 
lw395 said:
What voltage does it charge at now?
How reliant on the alternator are you for charging?
How much do you run your engine?
How much do you draw from the batteries when the engine's not running?
Do you have cash burning a hole in your pocket?
Click to expand...
Current charging voltage is 13.7 volts max. AGM data sheets state that they need between 14.6 and 14.8 volts.

Currently totally reliant when cruising

As little as possible,

My current power needs are 80 A hours per 24 hours, if I don't run the radar.

No cash burning a hole in my pocket, but setting up the boat for bluewater cruising and want to get this right.
 

So let's say the internal regulator reduces output because of excess heat. You fit some form of external device to squeeze more charging current from the alternator. How does the alternator then deliver this increase in output without getting even hotter ? Note that Sterling state "Alternator temperature sensing: This disengages the unit in the event of the alternator temperature getting too high, it then re-engages the unit when the alternator cools down. "

If you want to fit the A-B, fit it, but not because of worries about alternator overheating. You then leave the Cyrix out and connect the solar controller to the domestic bank.
 
Sandy said:
Current charging voltage is 13.7 volts max. AGM data sheets state that they need between 14.6 and 14.8 volts.

Currently totally reliant when cruising

As little as possible,

My current power needs are 80 A hours per 24 hours, if I don't run the radar.

No cash burning a hole in my pocket, but setting up the boat for bluewater cruising and want to get this right.
Click to expand...

Whether you choose to change your batteries or not, the alternator voltage is too low. Fit a new alternator (that charges at a higher voltage) or an external device to overridde the alternators internal regulator. Chances are, with such a low output voltage, the alternator is fairly old.
 
PaulRainbow said:
So let's say the internal regulator reduces output because of excess heat. You fit some form of external device to squeeze more charging current from the alternator. How does the alternator then deliver this increase in output without getting even hotter ? Note that Sterling state "Alternator temperature sensing: This disengages the unit in the event of the alternator temperature getting too high, it then re-engages the unit when the alternator cools down. "

If you want to fit the A-B, fit it, but not because of worries about alternator overheating. You then leave the Cyrix out and connect the solar controller to the domestic bank.
Click to expand...
Thanks Paul i am slowly learning thanks to all the help on here. Not trying to reinvent the wheel just understand why it is round ?
 
PaulRainbow said:
Whether you choose to change your batteries or not, the alternator voltage is too low. Fit a new alternator (that charges at a higher voltage) or an external device to overridde the alternators internal regulator. Chances are, with such a low output voltage, the alternator is fairly old.
Click to expand...
Thanks Paul, I am 100% convinced that it is the original that came with the boat. Its a Paris Rhône and I've not seen any of these in a long time.
 
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