New Sterling battery charger, which amp rating to choose?

[adrian's boat]

Dear all,

 

My trusty old Sterling battery charger has packed up and I'm looking at replacing it with the new equivalent, the snappily titled:

Sterling Power Pro-Charge Ultra 12V Battery Charger.

 

They do them in 10amp up to about 60amp, but I have no idea how many amps I would need to charge my single starter battery and my three domestic batteries (all four are 115amp leisure batteries).

 

Can anyone advise me please?

 

Adrian

[Robbo]

Dear all,

 

My trusty old Sterling battery charger has packed up and I'm looking at replacing it with the new equivalent, the snappily titled:

Sterling Power Pro-Charge Ultra 12V Battery Charger.

 

They do them in 10amp up to about 60amp, but I have no idea how many amps I would need to charge my single starter battery and my three domestic batteries (all four are 115amp leisure batteries).

 

Can anyone advise me please?

 

Adrian

 

How you powering the charger? Generator or Shore - If via shore then is doesn't really matter (in fact lower is better). Via generator then the larger the charger the quicker it will charge, but will degrade the battery quicker. 20% of the total Ah's is a good start. So if charging via generator I would get the 60amp, if via shore I would get a 40 or 30 - but even a 20 or 10 will be okay.

Edited November 4, 2013 by Robbo

[adrian's boat]

Thanks very much Mr Robbo.

I do sometimes charge from a generator, so a rapid charge would definitely be a benefit.

Annoyingly the 60Amp model costs £200 more than the 20Amp model, which may be a fatal factor.

 

Thanks again for your advice.

AA

[by'eck]

Thanks very much Mr Robbo.

I do sometimes charge from a generator, so a rapid charge would definitely be a benefit.

Annoyingly the 60Amp model costs £200 more than the 20Amp model, which may be a fatal factor.

 

Thanks again for your advice.

AA

 

I believe Puffer Parts still offer 21% off RRP on Sterling equipment. They also list a new but discontinued 40 amp 3 output digital model for £292.42 inc.

 

A few others offer 20% off.

[bottle]

Just an addendum to Robbo's post have a look here:

 

 

http://www.smartgauge.co.uk/chargesize.html

[Paul's Nulife4-2]

Hi ya,

I think that if you have a total battery capacity of approx 460amp hr.

Hopefully it would be safe to say that they will at worst be depleted to approx 50%.

So Lets say 230 to 250 amp.

It's fair to say that a good charger should reflect 10 / 15% of expected requirements (I think).

So I would look at a minimum of 30 / 40amp allowing for upgrades should be fine.( What size did you have ?). But that's just me. Happy hunting & let us know the outcome.

Edited November 4, 2013 by Paul's Nulife4-2

[adrian's boat]

Thank you all for your advice.

I've actually decided to go for one of these:

http://www.sp-shop.co.uk/Sterling-Power-ProCombi-S-12v-2500w-Sine-Inverter-Charger-PCS122500.html

It means I can rip out all of the following:

My battery charger

My 1kw cheap n nasty inverter

My 200w posh sine wave inverter

My mains switch over switch.

All of the above are getting on a bit and attract spiders, and trying to explain to other people the procedure for switching over from shore power to inverter has always been a bit tricky.

[adrian's boat]

 

I believe Puffer Parts still offer 21% off RRP on Sterling equipment. They also list a new but discontinued 40 amp 3 output digital model for £292.42 inc.

 

A few others offer 20% off.

Thanks very much for that. The 40 Amp charger is identical to the one that's just worn out. I got to thinking that if I was spending £300 anyway I may as well look at what else was wearing out, and worked out that I can replace almost everything with a Sterling Pro Combi thingy. It costs about £1000 (ouch), but will sort all my electrics in one go (with a smartgauge of course).

[by'eck]

Thanks very much for that. The 40 Amp charger is identical to the one that's just worn out. I got to thinking that if I was spending £300 anyway I may as well look at what else was wearing out, and worked out that I can replace almost everything with a Sterling Pro Combi thingy. It costs about £1000 (ouch), but will sort all my electrics in one go (with a smartgauge of course).

 

Good call. I have one as well. The 100 amp charger part puts out as much as 110 amps momentarily.

[Richard10002]

Thank you all for your advice.

I've actually decided to go for one of these:

http://www.sp-shop.co.uk/Sterling-Power-ProCombi-S-12v-2500w-Sine-Inverter-Charger-PCS122500.html

It means I can rip out all of the following:

My battery charger

My 1kw cheap n nasty inverter

My 200w posh sine wave inverter

My mains switch over switch.

All of the above are getting on a bit and attract spiders, and trying to explain to other people the procedure for switching over from shore power to inverter has always been a bit tricky.

I have one of these and wouldn't buy one again!

 

If you connect it to shore power to charge your batteries, and the shore power trips, it reverts to inverter mode. If you are away from the boat for any length of time, it flattens your batteries. I kept my old charger and fitted it between the shore power inlet and the inverter charger. Irritating, and Sterlings answer was more or less "tough".

 

When charging it generally runs at Absorbtion voltage for only an hour before returning to float voltage. An hour is usually nowhere near enough, and it is irritating to have to remember to switch it off and on every hour, and even more irritating when you forget, and find you have been at float for a few hours.

 

The recurring word with this unit is "irritating!".

 

You will also almost certainly need new cables to cope with the 2500W capability, and a big fuse.

 

If I had my time again, I'd get a 1000W Victron or Mastervolt.

[by'eck]

I have one of these and wouldn't buy one again!

 

If you connect it to shore power to charge your batteries, and the shore power trips, it reverts to inverter mode. If you are away from the boat for any length of time, it flattens your batteries. I kept my old charger and fitted it between the shore power inlet and the inverter charger. Irritating, and Sterlings answer was more or less "tough".

 

When charging it generally runs at Absorbtion voltage for only an hour before returning to float voltage. An hour is usually nowhere near enough, and it is irritating to have to remember to switch it off and on every hour, and even more irritating when you forget, and find you have been at float for a few hours.

 

The recurring word with this unit is "irritating!".

 

You will also almost certainly need new cables to cope with the 2500W capability, and a big fuse.

 

If I had my time again, I'd get a 1000W Victron or Mastervolt.

 

The latest ones have a charger only mode so this doesn't happen.

 

I have found that a few charge cycles from 50% SOC sets the auto bank sizing absorption phase timer to something around the correct time.

 

If as many do, you charge at greater than C/5 the charge current will drop off quicker, prematurely reducing the absorb mode time. Easily rectified by cycling off and on again.

 

My old Victron was worse because the absorb timer was fixed at two hours.

[Arthur Brown]

If you plan to use a 100A charger from shoreline or generator be very certain that the supply is sufficient for the significant load it will draw. That charger will draw lots of current from the supply.

[saltysplash]

I have one of these and wouldn't buy one again!

 

If you connect it to shore power to charge your batteries, and the shore power trips, it reverts to inverter mode. If you are away from the boat for any length of time, it flattens your batteries. I kept my old charger and fitted it between the shore power inlet and the inverter charger. Irritating, and Sterlings answer was more or less "tough".

 

When charging it generally runs at Absorbtion voltage for only an hour before returning to float voltage. An hour is usually nowhere near enough, and it is irritating to have to remember to switch it off and on every hour, and even more irritating when you forget, and find you have been at float for a few hours.

 

The recurring word with this unit is "irritating!".

 

You will also almost certainly need new cables to cope with the 2500W capability, and a big fuse.

 

If I had my time again, I'd get a 1000W Victron or Mastervolt.

We also have this model and find no problem whatsoever.

 

was fitted new with the boat 5 years ago and we are still on the same 5 yr old batts.

[adrian's boat]

Dear all,

 

Thanks partly to your advice my new Sterling Pro Combi is installed and working well with one exception, so I am seeking your further advice please.

 

The domestic batteries are only charging to 81% of capacity. The starter battery, separated from the domestics with a splitter, is charging to 100% no problem.

 

I suspect this is happening because the final stage of charging is at a voltage below that at which the splitter separates the circuits, so the domestics don't get a full charge. If I run the engine then all of the batteries charge to 100%, the engine alternator not being 'smart' and chucking out a consistent 14 volts.

 

I'm thinking of dealing with the problem by installing a Merlin Smartbank as I've already got the Smartgauge so it would only be another £100.

Will that solve the problem or am I barking up completely the wrong tree?

 

Regards,

 

AA

[Richard10002]

The latest ones have a charger only mode so this doesn't happen.

 

 

I can't find any reference to a charger only mode in the latest documentation or specifications. In fact, Sterling make a feature of the fact that,when the mains is disconnected, it switches to inverter mode, and when the mains is reconnected, it reverts to charging and 240V pass through mode.

 

From the online brochure at: http://www.sterling-power.com/images/datasheets/ProCombi%20Datasheet%20low.pdf

 

" The ProCombi is based on a single power module that can work either as an Inverter or as a battery charger. When mains power is available ProCombi operates as a powerful, fully automatic, multi stage battery charger simultaneously supplying the incoming power straight through to the on-board consumers. When mains power is disconnected the unit automatically reverts to operating as an inverter, supplying 230V from the battery, until mains power is again restored."

 

I remain of the opinion that you could not leave your boat charging with one of these, as it would flatten the batteries if the mains tripped, or the plug removed, or whatever. I would be interested to see an official reference to a charger only mode.

 

I'm not being pedantic, I just don't want someone to buy something that doesn't do what they wanted. I used to own a boat that I left on charge in a Portuguese marina when I came home for a few weeks. The charger was a charger only so, if the power tripped, it didn't charge and, if the power came back on, the charger resumed charging.

[adrian's boat]

I can't find any reference to a charger only mode in the latest documentation or specifications. In fact, Sterling make a feature of the fact that,when the mains is disconnected, it switches to inverter mode, and when the mains is reconnected, it reverts to charging and 240V pass through mode.

 

From the online brochure at: http://www.sterling-power.com/images/datasheets/ProCombi%20Datasheet%20low.pdf

 

" The ProCombi is based on a single power module that can work either as an Inverter or as a battery charger. When mains power is available ProCombi operates as a powerful, fully automatic, multi stage battery charger simultaneously supplying the incoming power straight through to the on-board consumers. When mains power is disconnected the unit automatically reverts to operating as an inverter, supplying 230V from the battery, until mains power is again restored."

 

I remain of the opinion that you could not leave your boat charging with one of these, as it would flatten the batteries if the mains tripped, or the plug removed, or whatever. I would be interested to see an official reference to a charger only mode.

 

I'm not being pedantic, I just don't want someone to buy something that doesn't do what they wanted. I used to own a boat that I left on charge in a Portuguese marina when I came home for a few weeks. The charger was a charger only so, if the power tripped, it didn't charge and, if the power came back on, the charger resumed charging.

 

It does indeed have a 'charger only' mode. '

 

Battery charger function utilises advanced multi-stage

characteristics and is suitable for permanent connection to

the battery. Adjustment is easily made via a selector switch

to accommodate alternative battery types.

 

The toggle switch on the controller has 'auto' 'charger only' and 'power save off' modes.

I'll post a picture of it if you want to see it (and there's nothing pedantic about doing things right)..

[Richard10002]

 

The toggle switch on the controller has 'auto' 'charger only' and 'power save off' modes.

I'll post a picture of it if you want to see it (and there's nothing pedantic about doing things right)..

Thanks Adrian,

 

A picture would be good, if only to satisfy me that Sterling has done what he said he would.

 

Cheers,

 

Richard

[bottle]

Adrian

 

reference your post # 14

 

Reading your splitter as a relay and that your charger goes to the start battery first and the relay splitter then connects the domestics.

 

Wire it the other way so that the charger goes to the domestic and the relay then connects the start.

 

So if the relay drops out the domestics still get charged and the start battery loses out.

 

The start battery will always get to fully charged first as it is only used for very a short time and hardly discharged

 

 

If I have read it wrong just disregard

[adrian's boat]

Adrian

 

reference your post # 14

 

Reading your splitter as a relay and that your charger goes to the start battery first and the relay splitter then connects the domestics.

 

Wire it the other way so that the charger goes to the domestic and the relay then connects the start.

 

So if the relay drops out the domestics still get charged and the start battery loses out.

 

The start battery will always get to fully charged first as it is only used for very a short time and hardly discharged

 

 

If I have read it wrong just disregard

 

That's crazy and massively counter-intuitive, but also makes really good sense. The only way that would go wrong was if you had to start your engine about 15 times without your domestic batteries ever reaching full charge, then your start battery may not have enough, but could be jumped from the domestics.

Thanks Bottle!

[Robbo]

 

That's crazy and massively counter-intuitive, but also makes really good sense. The only way that would go wrong was if you had to start your engine about 15 times without your domestic batteries ever reaching full charge, then your start battery may not have enough, but could be jumped from the domestics.

Thanks Bottle!

 

If you have a combi, then if it's the same as my Victron Combi then it will have only one set of main cables going to the batteries for charging and inverter use. You want these to go to the house bank as if they didn't you'll be using your starter battery when using the inverter part.

[bottle]

 

That's crazy and massively counter-intuitive, but also makes really good sense. The only way that would go wrong was if you had to start your engine about 15 times without your domestic batteries ever reaching full charge, then your start battery may not have enough, but could be jumped from the domestics.

Thanks Bottle!

 

I think you may be getting how the battery charging system you have works, if I am wrong I apologise

 

You have a voltage sensitive relay (ie when the voltage is high it connects and when low disconnects)

 

So your alternator or charger starts charging, the voltage goes above its connection voltage, both battery banks are connected together and each take what they want at the same time, the system does not charge one battery and then the others.

 

The relay should be controlled by the alternator and charger output,

 

The idea of the relay is that one charge source (alternator or charger) can charge both banks but be disconnected, so that one does not support the other, when no charging is taking place.

 

Agreed my scenario is crazy and massively counter-intuitive, and not the norm for a single alternator set up but I am only talking about the charger, the start battery should be more than adequately taken care of by the engine alternator.

 

My start battery is not charged by my charger only the alternator.

 

Taking this part of your post: I suspect this is happening because the final stage of charging is at a voltage below that at which the splitter separates the circuits

 

The voltage will only drop when the batteries go into float and if the domestics are not charged I do not see how it can.

 

It may be an idea to check where the relay is picking up its signal to engage.

 

Not trying to teach you to 'suck eggs' and/or confuse you, honest.

[adrian's boat]

 

If you have a combi, then if it's the same as my Victron Combi then it will have only one set of main cables going to the batteries for charging and inverter use. You want these to go to the house bank as if they didn't you'll be using your starter battery when using the inverter part.

I'm confused about it now.

I didn't fit it myself so I'm not quite sure how it's wired, however when it's running on inverter it's definitely using the domestic batteries as the voltage drops across them.

Thanks Adrian,

 

A picture would be good, if only to satisfy me that Sterling has done what he said he would.

 

Cheers,

 

Richard

Any idea how to post a photo here?

[bottle]

Adrian

 

Somehow I think your set up is normal and it is just the relay that needs looking at, it should not be dropping out until the charger/alternator are off.

[adrian's boat]

Problem solved! Thanks to the kind and wise advice of Simon from Isis Electrical I turned up the float voltage to 13.7 volts and it charges everything to 100%.

 

I recommend the Pro Combi set up, far less hassle than the multitude of things it has replaced.

[by'eck]

I can't find any reference to a charger only mode in the latest documentation or specifications. In fact, Sterling make a feature of the fact that,when the mains is disconnected, it switches to inverter mode, and when the mains is reconnected, it reverts to charging and 240V pass through mode.

 

From the online brochure at: http://www.sterling-power.com/images/datasheets/ProCombi%20Datasheet%20low.pdf

 

" The ProCombi is based on a single power module that can work either as an Inverter or as a battery charger. When mains power is available ProCombi operates as a powerful, fully automatic, multi stage battery charger simultaneously supplying the incoming power straight through to the on-board consumers. When mains power is disconnected the unit automatically reverts to operating as an inverter, supplying 230V from the battery, until mains power is again restored."

 

I remain of the opinion that you could not leave your boat charging with one of these, as it would flatten the batteries if the mains tripped, or the plug removed, or whatever. I would be interested to see an official reference to a charger only mode.

 

I'm not being pedantic, I just don't want someone to buy something that doesn't do what they wanted. I used to own a boat that I left on charge in a Portuguese marina when I came home for a few weeks. The charger was a charger only so, if the power tripped, it didn't charge and, if the power came back on, the charger resumed charging.

 

For several months now Sterling's full page advert in Towpath Talk has been advertising this addition to their Combi's. I guess it takes a while for brochures and instruction manuals to catch up.

 

A recent communication from Charles Sterling confirms it can be retro-fitted to earlier models with a new control system which is about £ 250!

 

May take a rain check on that although I wonder if its just a new remote with four position switch.