Sterling advanced regulator

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I am seeking the advice about installing a Sterling advanced regulator. I have read their technical sheet as to its capabilities, but would welcome any first hand experience from users, before I go ahead and purchase one.
My installation is basic, my alternator is 35 amp ona Perkins 4108, my batteries are 2 x 180 amp/h domestic, plus a 75 amp/h starter battery.
I am also considering upgrading the alternator to a 70 amp one, any suggestions as to whether this would be an additional help charging along with the advanced regulator.
I appreciate this may have been previously aired here but please indulge me.
 
Modern alternators tend to run at a higher voltage than older units, so if were to buy a new 70A alternator you could well find that it puts out around 14.4v, close to what you'd achieve with a Sterling add-on regulator. As a 35A alternator is rather small for today's needs, I'_d be tempted to fit a new 70A alternator and then review the situation.
 
Hi Sarnia
name reminds me of a refinery I used to know about in the old Yugoslavia

Here's my response to your query for what it is worth
1Check your alternator / new alternator internal regulator settings . I am assuming you batteries are open lead acid and not other types which require a lower charging voltage. ```Some new alternators on the market have settings 14.5 V and above as designed for the automobile industry with higher revving engines and not so much for the smaller marine market If so any Sterling or equivalent external alternator wont work on its own . I had this situation and system split charge relays cut out because voltage rose well above 17.5 volts not to mention some undetected damage to other equipment
2 Older alternators settings will be much lower etc and external regulators will work but you will need one for each alternator . Your engine Manufacturer may we worth approaching for a recommendation
3 I presume you already have diode split charging if so you might be OK even if alternator out put higher because of drop across diodes but depends on where you measure voltage from

4 Some pundits recommend alternator out put at least one quarter of your total battery bank capacity so you would seem under sized but when considering what you want to do and rate of charge you might want to consider alternators and engine linkage as a whole . For example some alternators only reach their peak out put at 6000rpm or greater which means that with a 2 :1 belt pulley ratio engine must be cruising about 3000 RPM which some engines are not designed to do on a continuous basis . Its more iikely 1800 rpm which results in less out put from the alternators eg an 80 amp alternator might only be able to acheive 60 amps on a particular engine /puley set up So you might want to consider larger alternators or as you suggest have two such devices . Alternator suppliers publish curves of RPM against amperage . I have some performance curves for Letrica ( Ikaria ) alternators which give full amperage at 8000 rpm and only start charging between 1000 and 1500 rpm depending on size .
5 So another issue which might bother you is at what rpm the alternators begin to charge such that the ignition light goes out . You may have to review your tick over speed
6 You might even want to play with pulley diameters depending on engine and external space and where you would mount the second machine
7 Check rotation direction of second alternator if facing engine ( existing alternator ) is only option as it may have to rotate in opposite direction . Most alternators are fitted with clockwise fan and an anticlockwise one is a special so specify what you want before buying . If you fit a clockwise instead it might affect cooling of the alternator as the fan sucks air through the alternator body rather than trying to blow into it . Not recommended by manufacturer

So select your alternators carefully

8 80 amps per alternator is the largest you could go with a single V belt so if you want to go higher you might have to consider multiple belt pulleys etc if its possible to fit them in your situation

Good luck



I am seeking the advice about installing a Sterling advanced regulator. I have read their technical sheet as to its capabilities, but would welcome any first hand experience from users, before I go ahead and purchase one.
My installation is basic, my alternator is 35 amp ona Perkins 4108, my batteries are 2 x 180 amp/h domestic, plus a 75 amp/h starter battery.
I am also considering upgrading the alternator to a 70 amp one, any suggestions as to whether this would be an additional help charging along with the advanced regulator.
I appreciate this may have been previously aired here but please indulge me.
 
I think I may have misled you, I am not considering having two alternators working together, just to upgrade/replace my existing 35 amp one to a 14v-70 amp.
The alternator I am considering has a performance curve from 1000rpm to 6000rpm plotted against the amps.
For example: 1200 revs = 10amp, 1500 = 20amp, 1800 = 30amp, 2000 = 40amp, 2500 = 50amp, 3000 = 60amp. 4000 = 65amp, and 5000+ = 70amp. as you can see the curve flattens at the higher end.
I would think my pulleys are at least 2 to 1 (alternator turns two times per engine rev) so I should achieve those outputs with engine at half those revs, I rarely run it over 2000 revs unless circumstances dictate anyway, so about 65 amps at engine 2000revs.

I do appreciate your careful and comprehensive reply, than you.
 
The proposed new alternator is rated 14v - 70 amp. so as you say it would be sensible to fit the new one and access the results before buying the sterling regulator.
The performance curve is as in my other answer to catmandoo, and it has a note : terminal voltage 13.0v ambient temp.23c.
Why is it rated 14.0v.

Many thanks for your input.
 
regulator out put varies with temperature spec sheet should show range from -40 to 120 deg c
20 deg C seems to be nominal set point on the curves I have got showing temperature against Ub+(v). Colder -voltage rises , hotter- voltage drops . Typical rate of change -10mV/deg C refers to std ISO 8854 Ub+=constant=13V t amb=23degC= or - 5degC

ISO 8854Specifies test methods and general requirements for the determination of the electrical characteristic data of alternators for road vehicles. Applies to alternators, cooled according to the manufacturer's instructions, mounted on internal combustion engines. Figure 1 shows a diagram for alternator testing. More details if you have 120 Euros to read standard
 
The question that needs to be asked is just what is your problem with the present set up. What is your style of usage and power needs. An amp meter showing actual charge current would be useful to see just how much current your present alternator is providing and for how long before the current tapers off.
A higher voltage altrernator/ regulator will give more charge for longer in an engine run be it for actual motoring or just battery charging. A smart regulator will give even more current for longer in an engine run period. But do you need it? Solar charging may be a better option unless you want to live aboard and run a fridge TV heater or similar.
As said acual charge voltage with presnt set up will also dictate charge current and for how long. A new alternator may increase voltage a little which will make a lot of difference.
good luck olewill
 
As olewill says, the first thing to fit before making any changes to your electrical system (whether Sterlings, solar panels, wind chargers etc) is a decent amp-hour counter. If you don't fit an amp-hour counter first, you have no way of understanding what is going on with your charging system.
 
I am seeking the advice about installing a Sterling advanced regulator. I have read their technical sheet as to its capabilities, but would welcome any first hand experience from users, before I go ahead and purchase one.
My installation is basic, my alternator is 35 amp ona Perkins 4108, my batteries are 2 x 180 amp/h domestic, plus a 75 amp/h starter battery.
I am also considering upgrading the alternator to a 70 amp one, any suggestions as to whether this would be an additional help charging along with the advanced regulator.
I appreciate this may have been previously aired here but please indulge me.

Yes I have a sterling regulator and it works well. But it wont necessariuly be much of a help to you.

Your alternators output is limited to 35 amps or thereabout be design. But its output voltage would rise and rise as the batteries filled up to the point where it would boil the batteries, so the alternator is also fitted with a voltage regulator Probably best thought of as a voltage limiter. So imagine your batteries are half empty. The alternator starts off charging at 35 amps ( likely rather less in reality and its voltage might only be say 13volts. As the batteries fill up, the voltage rises and the current starts to drop a bit. Eventually the voltage gets to 14.2 or whatever the regulator is set at, and goes no further. The current starts to drop sharply. Its all a bit like your toilet cistern - you know the way that it goes full blast filling up until nearing the top when it tails off.

What the sterling does is to raise that maximum voltage and therefore the rate at which the alternator charges but still with the 35 amp limit which it cannot affect. So your alternator charges at 35 amps for longer and gets the batteries fuller a bit quicker.. One caveat. If your alternator regulator is a modern one set at 14.5 volts max, then the sterling wont do much at all because there is a limit to the voltage that can be used - too much and the batteries gas ie you split battery water into hyrdrogen and oxygen. If its an old regulator that is set at 14.2 volts, then the sterling will help.

However, your real issue is that your alternator is too small for your battery bank size. So it will be charging at 35 amps when a bigger alternator could charge at ( say) 60 amps. Understandably, it will take longer to charge at 35 amps.

My recommendation would be to replace the alternator with a bigger modern unit with an output voltage set at 14.5 - forget the sterling which wont really do much with your current set up and wont help much with an alternator that runbs at 14.5 v..
 
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Thank you, your post makes a lot of sense and rhymes with what other forumites have suggested, I think a new one is the way to go, I just posted a couple I am looking at as replacements.
 
The diagram of their alternator sent to me from which I quoted the figures is a Prestolite: 66021147 marine Application.

Some of the Prestolite alternators have an adjustable regulator, enabling you to set your own optimum charge voltage. The 90A one I had on my last boat was one of these, and it was a good feature. The one you're considering doesn't have an adjustable regulator. You might take a look at the Prestolite 110-603 model; I think this is the same basic mounting dimensions but it has an adjustable regulator. It's easily sourced in the UK.
 
I have been looking for your recommeded model 110-603 but with little success other than from the USA, I did find one on ebay but had been sold.
have you any links to UK sellers or distributors please.
 
Certainly, you can get one from Adverc - adverc.co.uk

In addition to the alternator you recommended is this second one, the 12v90 whos fittings look more compatable.
PREST110-603 Prestolite 12v/90A S/ Pulley Single Lug (IR) 110-603
PREST12V90 Prestolite 12v/90A S/Pulley S/L Bosch Type 20150113

Would welcome your comments
 
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