Sterling Alternator to Batt Ch. & Hitachi alt.

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jaba

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Hi all,

I will be installing a Sterling Alternator to Battery charger AB1280. My alternator is an 80A Hitachi LR180-03C on a Yanmar 3jh4e. Has anybody any experience/knowledge whether this alternator is "battery sensed" or "machine sensed"? (if battery sensed the ABC wants the battery sense wire taken to the + terminal of the alternator). I include the electrical diagram: as far as I understand from the drawing, the alternator is machine sensed, but I am no expert.

Thks
j
 
I am also no expert and not familiar with this alternator.
But from the diagram my impression is that your alternator senses voltage at the engine control panel. I guess that would make it machine sensed in a way.
Also the regulation is on the negative, if that makes any difference.
 
My take on the problem

Looking at the drawing its not clear if the internal regulator is sensing from the battery or machine its self. Its not battery sensed in the convention way that the “Sterling” instructions would expect. Do not follow the instructions for converting to machine sensed, with this alternator it would cause the battery to discharge with the engine stopped. You could always send the drawing to Sterling for a definitive answer. Please post How you get on, good luck Michael
 
mjf107 said:
Do not follow the instructions for converting to machine sensed, with this alternator it would cause the battery to discharge with the engine stopped
Click to expand...
could you elaborate pse? (edit: I think I've understood: if you connect r and bat + there is nothing to stop a current flow through the field coil when engine off

mjf107 said:
"You could always send the drawing to Sterling for a definitive answer. Please post How you get on, good luck Michael
Click to expand...
done, but he said to ask hitachi as he does not know this particular alternator.
 
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jaba said:
could you elaborate pse? (edit: I think I've understood: if you connect r and bat + there is nothing to stop a current flow through the field coil when engine off

Yes that's correct its how I see it
Good luck with it Michael
Click to expand...
 
Is it the Alternator to Battery Charger or one on the alternator regulators?

I installed the AB1290 a couple of years ago with a Hitachi alternator on a Yanmar 4JH engine. It was pretty much as the circuit in the top diagram at this link

http://sterling-power.com/products-altbatt.htm

So basically the negative from the existing alternator regulator was left connected to the batteries. It was also connected to the AB charger.

I took both outputs from the regulator and led them to the charger input. I then connected the charger outputs to the appropriate batteries.

I must say I've been pretty happy with the performance.
 
Alternator to battery charger

If I understand correctly this type of charger takes a standard alternator system output and uses the power developed to charge a single engine battery to charge a domestic battery. it does this by taking the DC voltage around 13v and converting it to a higher voltage suitable for faster charging of the domestic battery.
As such the charger and domestic battery appear to the engine and alternator as just another load. Albeit a large load. The beauty of this system is that no modifications are needed to the engine alternator and regulator.
The drawing provided seems to me to show the alternator sensing at terminal R on the regulator. This is connected to the engine side of the "ignition" key switch. This is a worry in that if the switch is turned off with engine running you don't have a 0 volt sensing which would send the alternator into full charge so over voltage. Hence it would be better connected to the battery +ve or alternator output. Just ensure you disconnect battery when you leave the boat. (battery switch) Or leave as is and don't turn key switch off with engine running unless it also stops the engine.

If the existing alternator charging is OK then do not change it. just add the charger to feed the domestic battery.
(if the new controller is an alternator controller then disregard all above) good luck olewill
 
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jaba said:
could you elaborate pse? (edit: I think I've understood: if you connect r and bat + there is nothing to stop a current flow through the field coil when engine off

done, but he said to ask hitachi as he does not know this particular alternator.
Click to expand...

In your 2nd quote did you mean you actually sent the drawing or was it referred to on the phone, if its the latter send them the drawing and my comments if you like asking them to comment on my advice, wouldn't want you to invalidate the warranty if I've missed some point. By all means contact Hitachi they might just explain how or what it senses on, I would expect it would be broadly as Baba Yaga and William H have posted though. I doubt very much if they would be able to comment directly on interfacing their Alternator to the A-B charger. Not sure how Sterling are set up if they cant help you directly, maybe they have an approved installer in your area that has already come across this problem.
Michael
 
Thanks all, things are clearer now.

Alternator apparently is machine sensed (it doesn't have an S output). It doesn't seem to "sense" anything at R, which is only the ignition feed. But I am still investigating.
Cheers
j
 
It wold be worth e-mailing or phoning Sterling. Whenever I've tried contacting them I've had a very prompt response from Charles Sterling himself. Responses have been very helpful although rather ... erm ... concise.
 
That is a bog standard machine sensed alternator, with the addition of a 50 ohm resistor across the charge light. So it will start with a dead bulb.
When it is running the regulator senses the output voltage via the three auxillary diodes (4), and controls the field current to regulate the stator voltage upstream of the main diodes on the +ve side. The output impedance is therefore roughly that of the main diodes.

To convert it to remote sensing is normally a case of pulling more current out of the field (at the point labeled F), by connecting an external regulator in parallel with the internal one, thus raising the machine voltage above its set point.
 
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