Split charge

[lil_azza]

So im gonna put split charge into the van and have been on tow sure iv found this

http://www.towsure.com/product/SelfSwitching_Combination_Relay" onclick="window.open(this.href);return false;
This what I'm looking for? As the kits seem real expencive for what they are, I'm using a generator if that makes a difference ?

 

[lil_azza]

I guess no1 has used this? Or is it completely wrong ?

 

[gvee]

Based on the description it sounds like a good idea, especially when running a generator.
I have a cheaper option installed (standard 4-pin switching relay) but I do have a beefy alternator also.

 

[lil_azza]

I have a generator so u think this will work? Cheers

 

[gvee]

Disclaimer: electrics is not one of my strong points, so the following rhubarb may not be accurate, just my interpretation.
Please feel free to correct me where I talk nonsense!


A very simplistic view on alternator vs generator is that a generator won't charge the battery when the vehicle is idling i.e. it only provides enough juice when the engine is revving. I imagine that because you have a generator you'll find that your LB takes much longer to charge up.

This means that if you're running a generator it is already working really hard to keep your main battery topped up. Now imagine adding a second battery (your leisure battery) in to the equation. Will your generator be able to put out enough to keep your main battery topped up?

My simpler set up basically charges both batteries when the alternator is "running".

What you've found monitors your main battery and when it reckons that has enough charge, then it allows "excess" charge to be sent to the leisure battery.

 

[KateLovesPurple]

^^^ WHS

Although, a word of warning. Whether it is the same with all of these or whether I just had a faulty one, I don't know, but when I had one fitted I found that if the LB went flat, and mine did if left too long without running it as I had my stereo memory and alarm/central locking hanging off it at all times, my starting battery would also drain. Therefore there was obviously no complete isolation between the 2 batteries when the engine was not running. As I said, I don't know whether mine was faulty or not as I didn't replace it with another but went for the much simpler switching relay set up.

 

[lil_azza]

Oh right so are saying a lb is no good from an generator?

 

[KateLovesPurple]

Your dynamo will only be supplying a maximum of about 30A when it is running above about 1000-1200 rpm. Below this it won't be kicking out as much current. An Alternator will be kicking out its full current capability (45A or more depending on the alternator fitted) at a much lower rpm, i.e. tickover.

What this means is that with a dynamo fitted you only have a maximum of 30A to charge both batteries and run whatever electrics you need whilst driving. This could mean with a smartcomm fitted you won't charge your LB.

I have first hand experience of over demanding a dynamo, my old type 3 fastback had a 30A dynamo, no alternator option, and when driving at night in the rain with headlights on, wipers running and my stereo running with a 4 way amp and sub amp, I had disco lights! Every time the sub hit some heavy base the headlights would dim in time to the beat! Not good. I fashioned an alternator conversion for it and no more disco headlights!

If you want to be sure of charging a LB and your main battery then I would really go for an alternator conversion with a simple switching relay split charge system.

Just my opinion of course but since I took out the smartcomm and replaced it with a simple relay I have had no problems whatsoever.

 

[lil_azza]

Ok thats you have a link to to this relay if this is the way to go as the dynamo is a fairly new, item cheers

 

[KateLovesPurple]

You could use a relay like this:

http://www.ebay.co.uk/itm/12V-Heavy...arts_Vehicles_CarParts_SM&hash=item338283ef13

in a diagram like this:

Use the values shown for the components as follows:

30A dynamo:

40A relay
4mm2 39A cable
30A fuses

55A alternator:

70A relay
10mm2 70A cable
60A fuses

Although you could use the alternator values with the dynamo fuse values to give you the option to change to an alternator later. If you do change to an alternator then move the blue wire from the 61 pin on the regulator to the D+ on the alternator and the B+ on the regulator to the B+ on the alternator, assuming it is internally regulated.

 

[lil_azza]

Thanks very much i will order that and do it that way cheers

 

[70-CA-Panel]

aircooled works is also selling a split charge system with 20% discount at Busfest I think.
If you're not inclined doing it yourself.

http://forum.earlybay.com/viewtopic.php?f=33&t=61831

 

[lil_azza]

Cheers buddy il wire myself tho

 

[KateLovesPurple]

Just noticed I made a mistake in the specs which I have now edited. Should have been 10mm 70A cable. Sorry!

 

[lil_azza]

ok buddy thankyou iv ordered the relay u linked and a few larger terminals thanks