Club 80-90 Forums

v-lux wrote:

odd ball connectors

There's nothing odd ball about an anderson connector. Theyre industry standard for high amp connections. I would certainly much rather have an anderson connection charging a leisure setup on a trailer than try and put a decent charge down a piddly little trailer connection. The largest cable you can connect into any kind of trailer connection i have seen would not be anywhere near sufficient to allow a decent charge amperage.

If you have ever seen the connectors that AA vans have mounted front and rear for jump leads for instance.....Anderson connectors.....

Anderson Jack Plugs are used for High amp connections all right but charging batteries is not exactly High Amp. 13 pin Euro plugs use 2.5 mm cable for the auxiliary charging circuits which is totally adequate and well capable of 25amps continuous. These 13 pin Euro plugs are also ISO 11446 compatible which is the standard used in the Trailer/Caravan industry. These new plugs are specifically designed to carry charging circuits so why do you need a sledge hammer to open a nut!

Yes, I have seen the back of an AA van and yes, they do have Anderson Jack Plugs for jump start purposes, but we are not talking jump starting here, we are talking battery charging.

v-lux wrote:The standard route would be to have a 'S' trailer plug added to your van so that you can plug in the neccesary trailer plug connection to give the ability to charge a battery (or run a fridge etc etc, aimed at the caravan towing market)

Considering most people would need the secondary "S" plug adding to their van to allow charging anyway, i would imagine that to have a high amp cable attached from whatever split charge setup people have terminated in an Anderson connector would be a far more adequate setup. (and possibly cheaper too)
You would obviously still need the standard "N" plug to run the trailer lights, side lights, fog light etc etc.

The only advantage of having an "S" plug over the Anderson connector is that you have the option of having a reverse light, but im sure that wouldnt be that hard to rig up some other way.

I guess the difference is whether you are interested in having a 'decent' reliable power supply in the trailer, or just want a battery to provide some lighting. In an expedition/wild camping trailer i would personally prefer to have a decent additional power supply that could be relied upon.

As it happens i'm shortly going to be installing Anderson connectors to the front and back of my van just so i have the option of connecting a high amperage power supply should i ever need it. Perfect for jump starting without having to open up your engine bay, or connecting a compressor, or a winch, or......

These 'S' and 'N' plugs and sockets are being phased out. Go and check the 13 pin Euro plug. They have been around for years in European countries with the exception of GB.

As regards the charging of the auxiliary batteries, how much juice do you think is being used to keep the batteries topped up? If massive ampage was being needed then we would have huge cables in the vehicles charging circuits - which we dont! The charging cable to the 2nd battery in my Syncro are a VW fit 2mm!

When charging at 100 amps and 14.7 volts you need the 25mm cable that an Anderson connector can handle.



The Sterling allows you to charge your batteries without needing to drive for 14 hours.

Which car charging system charges at 100 amps? I know none of mine do.

Mine does

syncrosimon wrote:Mine does

Which one and what alternator have you got. I assume its a standard vehicle

viewtopic.php?f=2&t=74956

half way down. It is a very useful bit of kit.

syncrosimon wrote:https://club8090.co.uk/forum/viewtopic.php?f=2&t=74956

half way down. It is a very useful bit of kit.

Overkill IMHO and only really neccessary if you like stuff like that. For the application asked about here a standard system is what is needed. If these trailers are to be sold to Joe Soap, standardisation of parts is what is needed. Most vehicles have 12N and 12S plugs, newer ones have 13 pin plugs and they cope admirably with standard split charge relay systems. They dont have Anderson Jack Plugs or Sterling Charge Management systems fitted, they have the standard recognised stuff fitted. Bespoke systems like yours are great in bespoke vehicles but if this guy wants to manufacture and sell these trailers he has to go with the standard stuff or he wont sell very many.

I have a leisure battery under my seat, its in great nick and I run my main beams and spot lamps off it to keep it alive, God only knows how old it is and its only gone flat once - on the way to Syncro 25. I left the fridge on by mistake whilst on the Ferry from Roslare to Cherbourg! It charged up ok and holds its charge. No idea what my Alternator size is. I will look in the morning out of curiosity but I know I dont need anything bigger.

Difference is my battery system will last 4 days without engine start and then charge in 2 and a half hours. Horses for courses.

Having toured Europe for 9 months with a caravan I can say for sure that charging through a 13 pin (which is what I had) does not work to any degree that is useful. Charging quickly is the key in my eyes. This is what the sterling does. I spent 9 months trying to make the euro 13 it work, and ended up swapping batteries with the Range Rover to charge them.

I am wiring in a switch to connect the starter battery to the leisure batteries for in built jump starting. The headlamps will be modified then to run off the Sterling leisure batt side, so that the bulbs will be getting 14.8v, which will brighten them up nicely.

For sandwedge, being able to build bespoke I think will be a very important factor.

Simon/Spaddy
My plan was to have the trailer as an independent unit from the towing vehicle, I had thought it maybe possible to drive a 90amp alternator of the trailer wheel/s. My reasoning for this is there would be 2 charge sources so if one went down the other could be used, IE if towing vehicle alternator packed up and started batteries were drained, the trailer would hopefully be unaffected as it would not rely on the towing unit, so could be used for batteries or a jump start, or if common alternator used the trailer would be a source of parts.
The second use for the trailer alternator I had considered was using it in conjunction with a small wind turbine to act as a trickle charge unit.
This idea will be investigated once the main elements have been resolved, Im still not sure how to drive the charging unit reliable from the trailer hub.
I do see both of your points of view and both are valid, I do like the sterlin charger, however I would not want to rely on a complicated piece of electronics in an area that would not be able to repair it should it fail, I have the same reservations about the VW ecu, and some of the other electronic parts.

13 pin Euro plugs use 2.5 mm cable for the auxiliary charging circuits which is totally adequate and well capable of 25amps continuous.

What about the peak amps? When the battery is run flat after a few days of use its going to ask for much more 'juice' as soon as you start trying to charge it resulting in rather high amps.

As regards the charging of the auxiliary batteries, how much juice do you think is being used to keep the batteries topped up? If massive ampage was being needed then we would have huge cables in the vehicles charging circuits

After having done some extensive testing of the charging circuits of my van i have replaced all of my charging cables with 150A cabling as the existing equipment was certainly not up to the job from the readings given from a clamp style meter measuring amperage.

The charging cable to the 2nd battery in my Syncro are a VW fit 2mm!

Why would VW have focused on having a charging setup that is as fail safe and efficient as they could possibly make it, that's not their priority. Cost is their priority.

Most vehicles have 12N and 12S plugs, newer ones have 13 pin plugs

Most vehicles in the UK will probably not have a 13 pin euro plug fitted. They will most likely have a 12N..possibly a 12S aswell. As Syncros are not new vehicles i think we can assume that a 12N is the most likely. So this would require the syncro owner that wants a trailer to add a plug of somekind to their vehicle anyway, so why not add an Anderson connector. All it would cost is the price of a meter or so of cable and a connector - £15 tops.

Bespoke systems like yours are great in bespoke vehicles but if this guy wants to manufacture and sell these trailers he has to go with the standard stuff or he wont sell very many.

All depends how many people are going to want to drive an 'Expedition trailer' on an 'Expedition' with a standard unmodified vehicle towing it.

I have a leisure battery under my seat, its in great nick and I run my main beams and spot lamps off it to keep it alive, God only knows how old it is and its only gone flat once - on the way to Syncro 25. I left the fridge on by mistake whilst on the Ferry from Roslare to Cherbourg!

So...your'e saying that leaving your fridge on for a few hours ran your leisure battery flat?......I rarely ever turn my van fridge off, whats the point of a fridge if it isnt keeping things cool all the time? Do you turn off your fridge in your kitchen when you go to bed?

No idea what my Alternator size is

It should a be a 70A alternator, which is capable of delivering quite a bit more than its rated Amperage depending on the charge level of the battery its charging.... (i know this because i tested it)

What are you basing your comments on battery usage/charging on? How much time have you spent camping in your van away from civilisation and power supplies? How much wild camping/expedition equipment do you have/use that runs from the 12v system in your van? What Amps do the bits of equipment you have draw on your system? What is your daily Amp hr requirement? How long will it take to replace that usage with your current set up? Are you getting a true full charge to your secondary battery, if so, how do you know it is getting a full charge?

I think really the point here is that Sandwedge asked about ideas for "Expedition trailers" not standard trailers...there's plenty of those around already. Anyone who is intending on going for a bit of a jaunt offroad into the unknown with a trailer full of kit isnt going to sniff at spending a little extra on having equipment that can be completely relied upon. Why skimp on it? Id rather pay a bit extra and have the peace of mind.....

v-lux wrote:

13 pin Euro plugs use 2.5 mm cable for the auxiliary charging circuits which is totally adequate and well capable of 25amps continuous.

What about the peak amps? When the battery is run flat after a few days of use its going to ask for much more 'juice' as soon as you start trying to charge it resulting in rather high amps.

As regards the charging of the auxiliary batteries, how much juice do you think is being used to keep the batteries topped up? If massive ampage was being needed then we would have huge cables in the vehicles charging circuits

After having done some extensive testing of the charging circuits of my van i have replaced all of my charging cables with 150A cabling as the existing equipment was certainly not up to the job from the readings given from a clamp style meter measuring amperage.

The charging cable to the 2nd battery in my Syncro are a VW fit 2mm!

Why would VW have focused on having a charging setup that is as fail safe and efficient as they could possibly make it, that's not their priority. Cost is their priority.

Most vehicles have 12N and 12S plugs, newer ones have 13 pin plugs

Most vehicles in the UK will probably not have a 13 pin euro plug fitted. They will most likely have a 12N..possibly a 12S aswell. As Syncros are not new vehicles i think we can assume that a 12N is the most likely. So this would require the syncro owner that wants a trailer to add a plug of somekind to their vehicle anyway, so why not add an Anderson connector. All it would cost is the price of a meter or so of cable and a connector - £15 tops.

Bespoke systems like yours are great in bespoke vehicles but if this guy wants to manufacture and sell these trailers he has to go with the standard stuff or he wont sell very many.

All depends how many people are going to want to drive an 'Expedition trailer' on an 'Expedition' with a standard unmodified vehicle towing it.

I have a leisure battery under my seat, its in great nick and I run my main beams and spot lamps off it to keep it alive, God only knows how old it is and its only gone flat once - on the way to Syncro 25. I left the fridge on by mistake whilst on the Ferry from Roslare to Cherbourg!

So...your'e saying that leaving your fridge on for a few hours ran your leisure battery flat?......I rarely ever turn my van fridge off, whats the point of a fridge if it isnt keeping things cool all the time? Do you turn off your fridge in your kitchen when you go to bed?

No idea what my Alternator size is

It should a be a 70A alternator, which is capable of delivering quite a bit more than its rated Amperage depending on the charge level of the battery its charging.... (i know this because i tested it)

What are you basing your comments on battery usage/charging on? How much time have you spent camping in your van away from civilisation and power supplies? How much wild camping/expedition equipment do you have/use that runs from the 12v system in your van? What Amps do the bits of equipment you have draw on your system? What is your daily Amp hr requirement? How long will it take to replace that usage with your current set up? Are you getting a true full charge to your secondary battery, if so, how do you know it is getting a full charge?

I think really the point here is that Sandwedge asked about ideas for "Expedition trailers" not standard trailers...there's plenty of those around already. Anyone who is intending on going for a bit of a jaunt offroad into the unknown with a trailer full of kit isnt going to sniff at spending a little extra on having equipment that can be completely relied upon. Why skimp on it? Id rather pay a bit extra and have the peace of mind.....

I was going to sit down and reply to this but there is a lot to say there and some of it will be lost in the translation. Some of what you say is quite valid and I'm not arguing it and some of what you say isn't. Standard caravan / trailer charging systems work very well for millions of people - if they didn't then the market would be full of charging systems / plugs and sockets and wiring system like those you and Simon talk of.
The Aussies are good at making these trailers - look at their sites, look at the pics and you will see the sort of charging equipment I speak of and not the sort you speak of.

http://www.australianoffroadcampers.com.au/home.html A good site to get ideas from (look at the prices)

There are dozens of Expedition Trailer manufacturers in South Africa, America and Australia with a huge bank of knowledge about their customers and what they want and I would hazard a guess that the Aussies/Yanks/South Africans know a little more about Expedition Trailers and their customers needs than you do. They design their products to be able to be hitched up to the back of any vehicle and that is the key - simple standardisation.

The 'few hours' it took to flat my battery whilst running the fridge was in actual fact 23 hours which isn't bad I would have thought. Once the van was started and out on the road within 20 minutes the fridge was cold - standard system no issues!

syncropaddy wrote: Some of what you say is quite valid and I'm not arguing it and some of what you say isn't. Standard caravan / trailer charging systems work very well for millions of people - if they didn't then the market would be full of charging systems / plugs and sockets and wiring system like those you and Simon talk of.

The battery charging system incorporated into most camper conversions and caravans is equivalent to attaching a slow charger to your leisure battery. When trying to wild camp in the caravan the battery was simply not getting enough juice to properly charge. (there is a big difference in how much energy is stored in a battery from what method is used to charge it) This is the standard for caravans. Most 12n plugs just provide power to run the fridge and are capable of little else. But this does not matter with most tourers because they will 'hook up' on arrival at the campsite, and the battery might get a decent charge (again depending on the type of charger used) So for most caravaners this poor charging does not matter, as the caravan is not used without a hook up.

The Sterling system was developed for yachts where the main engine would need to be fired up specifically for the purpose of charging the batteries when at sea. This system just makes sure that the batteries have the maximum amount of stored energy and this is achieved in the shortest time. Plus the system can be added to using the Anderson plugs to charge 4 or 5 or more batteries.

This system is useful to people with a high current draw, that free camp, and dont want to drive around all day trying to charge the batteries. this obviously is not going to be everyone.

we survived 4 days in Copenhage without hook up, which saved us around 20 euros, we have also used this in Corsica, and when winter camping with the webasto on, two fans, lights, computer and radio the voltage did drop enough to stop the webasto from firing up, but 5 minutes with the engine running at 115 amps was enough to get the batteries going again. This would not be possible to do with a standard charging system. this is not going to be for everyone, and is tailored adsactly to my needs based on 20 years of fighting with dodgy charging circuits and flat batteries.

I have coupled this to a sterling 4 stage 30amp mains charger for when hooked up, this charges independantly the starter battery and the leisure batteries, then theres the 800w inverter that will run my angle grinder etc. Over the top yes definately, essential no, but bloody nice to have and the best system i have come across, yes.

syncrosimon wrote:Over the top yes definately, essential no, but bloody nice to have and the best system i have come across, yes.

Totally agree and certainly if I needed a system like that then I would look to the Marine Industry as they have some very serious stuff there - they need to. Even still 'Expedition Trailer' manufacturers need to build their products to a standard so that you 'hitch up and go' so therefore they have to use the old 12S and 12N or 13 pin Euro plugs. What the purchaser does with it after he has bought the thing is up to himself. There will be owners who will not want to go to the lengths you and vlux will go to and couldn't care less what amps are charging their batteries as long as it works.

Going back to the Aussies and their trailers, unprepared adventurers with ill spec'd equipment dont come back out of the bush! How long would you last as a manufacturer if your customers perished because your equipment was rubbish

No one here has mentioned solar power for charging. Even windmills got a mention ....

Just on the subject of sterling systems when I was looking at split charge systems I consulted a marine electrician who recommended a vsr which is for marine use. He thought that sterling systems were overpriced and overcomplicated and that sterling basically spoke a lot of rubbish about split charging on his site to promote his own products. I went the route he recommended and bought a marine vsr had one in my first van and a newer version in the Syncro which is more like a switch that you can override and connect the 2 batteries together eliminating the use of jump leads. http://www.merlinequipment.com/page/document.asp?id=135
Just clarify this point I have never tried sterling systems and am not putting down Anyones system or trying to cause offence just passing on what was said to me. Another alternative would also use traction batteries which can last up to 3 months as camping loads and are charged off the mains thus eliminating split charging issues altogether