Quick Question, Charging LB, are these any good?

[BashTheBongo]

Im a total blank out when talking about amps , watts n volts etc.
but we are putting a leisure battery on our bongo and need to know if this type of unit is suitable or not? ANd if so would it need anything else added?
LB is about a 100-1-5 ish amp.
and won't be heavily drained other than a laptop, phone, led lights and tap pump that only runs when water is running.

http://www.ebay.co.uk/itm/151550930756? ... EBIDX%3AIT

From a safety point of view it seems ok but,
I'm sure that "seems" and ARE" are not always the same.

If its not suitable, can anyone advise of a suitable, complete kit?
thanks.
Neil

[Diplomat]

Unless you are going to use an 'ad hoc' jumper between the two batteries (not advisable but it worked well enough for me in a VW with batteries easily accessible behind the seats until I got round to fitting a relay), you will need something of that sort anyway.

Consider also a mains charger for use on site hookups.


Frank

[g8dhe]

The 30 Amp relay and 20 Amp fuses are only just adequately rated, first time you flatten the LB battery the chances are the 20 Amp fuses will blow next time you start your engine.
The kit only arranges to charge the battery how are you planning on connecting the circuits you want to switch across from the SB ?

[BashTheBongo]

was planning on the SB doing all the normal stuff up front and just the rear light when door is open.
LB would be wired just for the rear accessories (1 wire from the + terminal to the rear, items earthed at the rear.)
So an x2 cig lighter socket for laptop and phone.
LED lights for standard lighting usage.
The tap/motor/pump only switches on when tap is turned on.

Will be using coolbox for now. not too worried bout a fridge until next camper.

So the SB would run all normal. and the LB would only be for the rear accessories.

QUESTION HELP PLEASE G8DHE?
not sure, how could the fuse blow?
The way I see it, (defenitly no expert here BTW )... on starting, it would only pull from the SB, and not kick in the connection until the voltage on the SB reaches a certain voltage (lets say 13v) then the voltage from the alternator would charge both batts until engine is turned off severing the connection.
Is that how it works or have I misunderstood it?
(there was another one I had seen with more info but i can't find that one now.)

thanks for the help all
Neil

[g8dhe]

You really need an extra wiring loom to transfer the 4 normally moved circuits from the old fusebox across to the LB, then things like Radio, cigarette sockets, internal lamps will all run from the LB. You can then add any more like fridge, taps extra lights as needed. However to do that you need wires running from the old fuse box to a new one powered from the LB, these are available either from Ebay or get the whole lot with an adequately rated relay and wiring etc. from say http://www.solarcampersolutions.co.uk/i ... 1-bongovsr who is also known as "Dodgy" on this forum!

The 20 Amp rating for the fuses is inadequate as when the LB is really flat then the charging current when you first start the engine can be a lot more than 20 Amps, typically 30+Amps for several seconds before some charge is put into the battery, this will almost certainly cause one of the two fuses to blow - allways change BOTH fuses if one goes as they are in series and one will melt just milliseconds before the other one which is then left working but damaged and often then pops at the next most inconvenient time

Oh and beware that coolboxes are lethal to LBs, they draw a constant 4-5 Amps and will flatten the best LB in less than 12 hours, whilst a compression fridge will run for 3+ days whilst static giving you a chance to charge the battery the with runs during the day.

[jimmo62]

You should also probably replace the scotchlock fuse holders in that kit with something a bit more reliable because they don't really have adequate contacts to maintain good pressure on the fuse. I had some like that any after a year I had to replace with something better as the LB was no longer charging.

[scanner]

You should also probably replace the scotchlock fuse holders in that kit with something a bit more reliable because they don't really have adequate contacts to maintain good pressure on the fuse. I had some like that any after a year I had to replace with something better as the LB was no longer charging.

Ditto.

Using Scotchlocks is only creating yourself a future problem, they really are the most hateful electrical item ever dreamed up.

Forget that they weren't dreamed up, they were nightmared up.

If you are going to join wires do it properly.

[BashTheBongo]

thanks all, will have a look at the system again

[Dodgey]

Interestingly , I've found that of the two customers who contacted me asking why the 30 amp fuse/s had blown, both were thankful that they had found out this way that they were over discharging thier leisure batteries, rather than the problem being ignored and killing the battery over time with repeated over discharging

So the 30amp rated system actually serves as a battery abuse warning system ( you won't approach 30 amps unless you properly over discharge your battery)

[Diplomat]

Perhaps these devices need some kind of surge limiting resistor in series with the charge which can be shorted out when the current settles down and then allows adequate potential difference to bring the leisure battery up to its maximum design voltage. Either that, or use a much heavier charge circuit fuse. The load circuits should all be protected with appropriate fuses fed from the battery terminal after the charging circuit, anyway, in a well designed system.

Regarding those fuse holders mentioned, I googled them. Aaagh! I think I might support Scanner if it gets as far as a libel case!


Frank

[scanner]

Regarding those fuse holders mentioned, I googled them. Aaagh! I think I might support Scanner if it gets as far as a libel case!


Frank

Not fuse holders, just wire joints. A job they are OK(ish) at for a short while - until they get a bit damp

One of those cost me money on my motorhome.
The fridge stopped running on 12v and the leisure battery stopped charging. The local auto electricians took about an hour checking the circuits before they found a Scotchlock on the trigger side of the relay that powered the fridge etc. had nearly cut through the wire it was connecting to. Total bill was about £60, a proper connection in the first place could have saved that.

[helen&tony]

Hi
Er...yes, I had similar when I had a firm out to fit a towbar for me back in the UK...A well-known mobile towbar fitting company. We didn't have time to do the job ourselves, as we were packing to move here. The whole wiring was done with scotchlocks, exposed to the damp behind the light clusters. I totally rewired it and the mess they caused when I got here. We were darned lucky it made the journey without failing. Quite a few more bits were wired using scotchlocks, and it has taken a long time to repair most of it! If you think scotchlocks are bad, the Bulgarian method of wiring , both mains and 12volt , is to twist wires together and tape them...no joint at all!!!!!!...It actually beggars belief!
Cheers
Helen

[cmm303]

Warning, cat amongst pigeons! I DIY fitted many of my tow bar, yonks ago, using the supplied scotchlocks. Whilst I agree and understand their weaknesses, I never experienced a problem. Some vehicles I hung onto for several years.
Insulation Displacement connectors are used extensively in the telecoms and electronics industries. So they can't be all bad. Maybe just not ideal for the vehicle environment or the variety of cable specs found in cars?

[g8dhe]

The problem with scotchlocks and the like is that the size of the actual wire is critical to the connection, yet there are only 3 sizes normally available in Scotclocks. When you use an IDC it should create a weld between the wire and the contacts, but for that you need control of the wire diameter better than 0.1mm in general and yet there are at least 3 overall types and 5-9 sizes in each one! Get the right size and they do work acceptably but the wrong size and they cut the wire or the wire falls out
Color Conductor Sizes

Black 12 AWG / 10 AWG Stranded (2)
Brown (3) 18 - 14 AWG (Tap) (2)
Yellow (2) 18 - 14 AWG (Tap), 12 - 10 AWG (Run) (2)
Red (5) 18 - 16 AWG / 14 AWG Stranded (5)
Blue (5) 18 - 16 AWG / 14 AWG Stranded (Tap) (3)

[rita]

The problem with scotchlocks and the like is that the size of the actual wire is critical to the connection, yet there are only 3 sizes normally available in Scotclocks. When you use an IDC it should create a weld between the wire and the contacts, but for that you need control of the wire diameter better than 0.1mm in general and yet there are at least 3 overall types and 5-9 sizes in each one! Get the right size and they do work acceptably but the wrong size and they cut the wire or the wire falls out
Color Conductor Sizes

Black 12 AWG / 10 AWG Stranded (2)
Brown (3) 18 - 14 AWG (Tap) (2)
Yellow (2) 18 - 14 AWG (Tap), 12 - 10 AWG (Run) (2)
Red (5) 18 - 16 AWG / 14 AWG Stranded (5)
Blue (5) 18 - 16 AWG / 14 AWG Stranded (Tap) (3)

As usual Excellent information from an Expert.