Sterling Alternator regulator

[galeus]

Struggling with various electrical problems one of which is the wire soldered in the alternator for the Sterling Digital regulator.It,s either green or white and runs up to the regulator.In Sterlings blurb it mentions you might like to pull this wire off to see the effect of the regulator, particularly in a less powerful boat as it could slow you down when you least needed it.I have put a illuminated switch in mine so you can see when its on;it has 3 terminals ,one going to power ,the other 2 to break the wire.Will this have any adverse effects on the system.I,ve phoned Sterling but Petes gone away for 2 weeks to France and the other fella only knows about battery chargers.I,m out of the water till next week so can,t test it out but after a quick wurr of the starter motor got a dim fluctuating light that petered out.Any advice gratefully considered.

Thanks Galeus /forums/images/graemlins/confused.gif /forums/images/graemlins/confused.gif

 

[roly_voya]

Not sure about this as the wire takes the regulated output to the alternator, the voltage is determined by the output require so wil vary from 0 - 12v, this may be why you see a fluctating light. The light might also mess up the reguation by adding a risistance but at least make sure you can't get any current leakage from the supply feeding the light to the alternator or you will lock the alternator on full output! This would only be needed if you have a low power engine and high power alternator and to put it into context a 100a alternator draws approx 2kw max. A typical 65a alternator pushing out 40a is going to be arount 750w. Most engines are set up with at least a 10% power reserve and more modern boats usually much more so unless you have an unusually small engin or larg alternator I would just wire it in. Never noticed any drop in revs on mine even when I switch in the kettle or fan heater.

 

[VicS]

I share Roly Poly's concern about the effect of the illuminating lamp although i think I interpret your description of how it is wired differently.

I think than when the switch is ON for normal operation the bulb will be feeding some extra field current into the circuit from positive. Maybe that will be important or not I'm not sure. possibly not.

When the switch is off you will either be feeding that current to the field coils which will mean the alternator will still be generating a little (and the switch will be illuminated) or it will be connected to the regulator output which probably wont matter.

That's assuming positive regulation and that your third connection goes to positive.

I'd have to draw out the circuit for negative regulation before commenting on that.

 

[pampas]

fit a double pole switch,one side for the Sterling circuit the other for your light. As your present circuit WILL defeat the booster regulator and could lead to a very pricey renewal of equipment.

 

[bluedragon]

I'm not sure what the light will do, but I have a switch in the output wire from the Sterling booster and do need it to ensure the unit is out of circuit when starting cold with a low charge service battery. Another option is to put the switch in the power supply to the Sterling and switch it off in this way. It's not Sterling's recommended procedure, but I did discuss it with them and no harm is done...it'll just keep re-setting the unit to its start-up mode, though this might cause over-charging if done often enough during an engine run. Actually I am going to do this for quite specific reasons in our set-up.

On the other hand, if you have a powerful engine and smallish alternator, forget the switch altogether...you don't really need it. Drop the battery down to say 50% charge and check if you get a noticable drop in rpm when the unit is switched-in whilst under propellor load...you could do this at the pontoon. If no rpm drop then your engine is easily coping with the extra load from the alternator. Ours doesn't and that's why we need the switch. Hope this is all clear!!

 

[VicS]

[ QUOTE ]
fit a double pole switch,one side for the Sterling circuit the other for your light

[/ QUOTE ] That's an excellent solution. Using a separate indicator lamp instead of an illuminated switch. I do think you are being a bit pessimistic about the effects of the illuminated switch though.

 

[galeus]

Good Idea,double pole switch it is,I want the switch primarily as a safeguard,it sort of makes me think I,m in charge.Thanks for all your input.
Galeus

 

[Billjratt]

I used a relay, physically close to the alt and sterling unit, controlled by an illuminated switch. greater cost but shorter wires. Have to say didn't use the disconnect function, purely diagnostic, and it never broke.