Disco 3 (LR3) Split charge

dieseldog69 said:

I will warn you now that for as good as the 200A rating sounds for the Tmax solenoid, I killed mine when the starter battery died and I linked the two batteries via the controller to start the Disco, it welded the contacts in the solenoid! I've replaced the solenoid and it's been golden since, although it is probably going to be removed in the not too distant future when I bolt on a second alternator with a 200A rating to feed the aux battery and the winch. Future jump starting can be done through my set of jump leads (which, in hind sight I should have used in stead of linking the two batteries through the solenoid ).

I am planning a whole new aux harness and fuse/relay boxes, got a load of diagrams to draw out for it and maybe I am going to put two 620SE-OPP Exide Heavy Professional Power EG1806 12v 180Ah 1000CCA behind the seats, one as main battery and the other as the aux, it should take about 80lb off the nose of my Disco and put that and the extra weight in the center of the truck, mine is a commercial with no back seats and a bulkhead over the foot well where the batteries will live, trunking and the fuse/relay boxes can be turned into a super neat installation from there I think?

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quick update , well u know u mentioning welding a solonoid, lol

my main battery went flat , pressed link, nothing

so after investigating with a multimeter, i got 12 vdc from the aux battery at the solonoid terminal

then tested the other side of the solonoid, nothing , so basically no power was coming through the solonoid from the aux battery to the main one

plus i was trying to work out what the other wires did onto the solonoid and how it switches over internally

contacted the company and no probs as there sending out a replacement solonoid

they did say for the 100s they’ve sold never had an issue , i’m wondering if at some stage it might be a good idea to find an alternative solonoid, will install the new solonoid in for now and see how it goes

noticed it’s rated for 250 x amps and see there is a winch solonoid which might have a higher amperage ??

just a pain having to take a lot of stuff out to replace it, the main battery was flat and wouldn’t even unlock the landy

wondering if it had welded the contacts together in the solonoid , surely i would have got 12 vdc the other side of the solonoid

apologies this post is so long winded, lol

They normally weld closed completing the circuit.

Main battery not having enough life to power the switch was your problem, I bridged mine to engage the solenoid.

Double check solenoid operation

dieseldog69 said:

They normally weld closed completing the circuit.

Main battery not having enough life to power the switch was your problem, I bridged mine to engage the solenoid.

Double check solenoid operation

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mmmmm, now you’ve got me thinking , aux battery had a full charge and that was fine

looking at the t max wiring diagram ive been pondering how it works, as i see u can cut the blue wire and put it onto a earth , as per u saying bridging it

plus have u seen the winch solonoids plse, been trying to look. for a wiring diagram in how the internals work , been pondering about a few ideas , lol

thks

NEW PRESTOLITE 12 VOLT 4 TERMINAL 200 AMP CONTINUOUS DUTY SOLENOID FITS 15-133 | eBay

This is the one, has to be continuous duty as it connects and then stays connected until you stop the engine, the VSR in the Tmax black box says disconnect and voila reconnects once the VSR detects starting battery has hit 14.4V

dieseldog69 said:

NEW PRESTOLITE 12 VOLT 4 TERMINAL 200 AMP CONTINUOUS DUTY SOLENOID FITS 15-133 | eBay

This is the one, has to be continuous duty as it connects and then stays connected until you stop the engine, the VSR in the Tmax black box says disconnect and voila reconnects once the VSR detects starting battery has hit 14.4V

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many thks and appreciate the link , this was the other one i saw

https://www.ebay.co.uk/itm/500amp-R...563140&hash=item4183b51aef:g:wlYAAOSwa39Uypoc

thought it was interesting

been reading about those other VSR systems, because i’m led to believe my alternator is a smart one controlled by an external controller, as it goes up to around 15.7 Vdc which some VSR systems don’t like

again, i don’t know 100% if this is true or not, still learning , lol

just thought the winch styled solonoid could be useful , not using a winch but then having a switched live but only on the aux side , don’t worry will explain better when i’ve tried to work it out, lol

The Albright winch solenoids are pretty good, the Tmax style is the can type with 6 posts, some of the solenoids are different and have two power supplies and use the body of the can to earth the unit so be careful if you replace it with an aftermarket unit, the intermittent solenoids are for starters.

The D3 alternator is also smart as in it has an internal clutch and disengages to freewheel when there is no load on it to save fuel and performance/load on the engine.

dieseldog69 said:

The Albright winch solenoids are pretty good, the Tmax style is the can type with 6 posts, some of the solenoids are different and have two power supplies and use the body of the can to earth the unit so be careful if you replace it with an aftermarket unit, the intermittent solenoids are for starters.

The D3 alternator is also smart as in it has an internal clutch and disengages to freewheel when there is no load on it to save fuel and performance/load on the engine.

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many thks and great info , i will indeed replace the original T max solonoid with another one when it turns up later this week

i meant to ask if i may , i ensured i installed fuses next to both batteries , aux is 70 x amps and main is also 70 x amps

i’m wondering if the main battery cable fuse is too small, that goes onto the solonoid , reason being when i crank the engine it’s surely got to be close to the 70 x amps

cable is rated to 110 amps , trouble is i can’t get a meter on whilst cranking the engine to accurately test and see what the results are

it’s so that i can buy some spare fuses and keep them in the landy and not get caught out if the fuse ever blew , wonder if 90 x amp would be more suitable, as of course i know i need to keep the fuse rating lower than the 16mm cable so the cable doesn’t end up as the fuse

many thks

I was going to fuse the solenoid supply but figured that the 250 amp rating was enough to save a battery should it over load.

Probably should fit a 100A fusible link in the line feed out.

dieseldog69 said:

I was going to fuse the solenoid supply but figured that the 250 amp rating was enough to save a battery should it over load.

Probably should fit a 100A fusible link in the line feed out.

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thks, will order some , there only a few quid , shall i leave the aux battery feed at 70 x amps or change that to 100 x amps as well plse

these are the fuses i’ve used

http://www.simplysplitcharge.co.uk/store/index.php?route=product/product&path=85_84&product_id=815

thks

70s plenty, what is the likelihood of you drawing harder than 70A at any one time? If it blows in use then assess the loads and if necessary uprate.

dieseldog69 said:

70s plenty, what is the likelihood of you drawing harder than 70A at any one time? If it blows in use then assess the loads and if necessary uprate.

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cheers , always good getting a second opinion , just released ive got some multimeter extension leads so might be able to lay the meter on the windscreen, crank the engine and see what amperage reading i get from the main battery

having the clamp meter , i could compare it with that as well