Second alternator on Disco

[team_little_legs]

hi well iv put a second altinator on my discovery and want to wire it stright up to second battery, has anyone done this ?

[101RRS]

My 101 has a second alternator and is wired directly to my second battery - the harder (not hard) part was wiring up an alternator light for it.

Why did you put in a second alternator - my truck it 24v so the second alternator provides 12v power.

Garry

[team_little_legs]

oh i tried going stright to battery but doesnt seem to charge untill i touched an eath to B+ on back of alinator then it charges at 14 volts ?
then i turned the car off and back on again and had to do the same thing to get it to charge ?

and just a second set up for winching and running my stero

[SouthOz]

I seem to remember some thing about needing to excite the diodes by fitting a light in the system. (charge light)

http://www.alternatorparts.com/FAQ.htm


EDIT extract from Google "Welcome. The wire to excite the charge circuit should be ignition power and run through a bulb in the dash. This circuit provides 2 uses. First is to send power with the ignition on and once it is all running, if there is a fault, the voltage regulator will ground the wire as it does when the alternator is not turning to indicate a problem. A simple 194 bulb is more than enough to do this.

Read more: How to wire a Delco alternator to excite it to charge - JustAnswer http://www.justanswer.com/heavy-equipment/31tin-wire-delco-alternator-excite-charge.html#ixzz20BQZCSqz"

Thanx
Dave

[bee utey]

I seem to remember some thing about needing to excite the diodes by fitting a light in the system. (charge light)

Alternator FAQ, Frequently Asked Alternator Questions answered (http://www.alternatorparts.com/FAQ.htm)

Thanx
Dave
Yup. Wire a light bulb for the second alternator between the ignition switch and the alternator D+ terminal, to replicate the wiring of the original system. Or use a relay, so that the bulb is wired from the extra battery and D+ only while the ignition is on.

[101RRS]

oh i tried going stright to battery but doesnt seem to charge untill i touched an eath to B+ on back of alinator then it charges at 14 volts ?
then i turned the car off and back on again and had to do the same thing to get it to charge ?


You only asked if someone had done it - not how to wire it up.

You just need switched 12v to excite the alternator (to the relevant point on the back of the alt) and run the +ive to the +ive on the battery - as long as the alternator is earthed the -ive of the battery just needs earthing.

[team_little_legs]

thanks for the help ill give this a try if falls ill write up what iv done... also its a standed 200tdi altenator where is the d+ on it ? i can only seem to find "W" and B+ ?

[bee utey]

thanks for the help ill give this a try if falls ill write up what iv done... also its a standed 200tdi altenator where is the d+ on it ? i can only seem to find "W" and B+ ?

Sorry was just looking at a spare Bosch alternator, just use the same connection that normally has a brown/yellow stripe wire attatched, that's the wire to the dash bulb.

[Lotz-A-Landies]

The thread that includes the discussion of Garrycols 101 dual alternator system is here: http://www.aulro.com/afvb/101-forward-controls-variations/110157-wots-been-happening-101-world-5.html#post1313532

[DeanoH]

hi well iv put a second altinator on my discovery and want to wire it stright up to second battery, has anyone done this ?

Why ? :confused:

Deano :)

[team_little_legs]

im going to run it as a winching battery, and a jump start it off the second battery if i need.

eventualy ill change the 12v alternator over for a 24v and run 2 optima's in the back for highmount winch

[PhilipA]

I have fitted 2 alternators in an RRC 3.9 and have 2 separate systems.

Why, because the second alternator will charge the second battery much quicker than when the poor old alternator is trying to also run aircon etc etc. You also have a backup alternator in case the first alternator dies, as mine did in Kakadu. All you do is pull the wires of the first alternator and bridge the + of the batteries. I also have provision to run spots from the second system to balance the load a bit.
The only difference to what you are talking about is that I have a relay controlling the ign light, and I have the light inside on the console , so that it comes on with the ignition and goes out when the alternator charges.
I now also have fitted an ABR dual battery controller through a 60/80 amp NC relay, so that the batteries are connected down to 12.4 volts, then disconnect.
I have an ignition on wire to the relay trigger that switches the relay to the unconnected B when the ignition is turned on. The batteries reconnect from the surface charge of the starting battery being above 13.2 when the ignition is turned off. They then stay connected until the starting battery is down to 12.4.
I hope to have the Engel run several more hours with this.

Just in case I just bought a 120W folding solar panel, so the sun will not shine in Queensland for the next 2 months.
Regards Philip A

[team_little_legs]

that sounds like a well thought out system. have you had any faults with the relay insted of just a globe ?

[PhilipA]

that sounds like a well thought out system. have you had any faults with the relay insted of just a globe ?

No, I have had no problems.
If you do not have a relay the light will be on all the time, and although they only draw 4watts , this will flatten the battery over a few days.

All cars cut off this circuit with either the ignition switch or a relay.
All you have to do is find a ignition on circuit to trigger the relay.
In my case there is one near the LH battery which I think is an unused headlight adjust circuit.
Regards Philip A

[Roverlord off road spares]

and just a second set up for winching and running my stereo :Rolling:

[team_little_legs]

its a big stero :D gotta have some rediclues bass when your up the bush

[gavinwibrow]

No, I have had no problems.
If you do not have a relay the light will be on all the time, and although they only draw 4watts , this will flatten the battery over a few days.

All cars cut off this circuit with either the ignition switch or a relay.
All you have to do is find a ignition on circuit to trigger the relay.
In my case there is one near the LH battery which I think is an unused headlight adjust circuit.
Regards Philip A
Silly/uninformed question? Could you not just fit a better alternator?

[oztrax]

Hi all,

anyone got pics of dual alternator install ?

prefer D1 tdi but any other install i am interested

regards
OZ:p:p

[PhilipA]

Silly/uninformed question? Could you not just fit a better alternator?


Mine was on a V belt V8 and a V belt will not run more than 85 amps reliably. In fact in 93 LR bought out a hybrid( Heath Robinson) sytem of a multi rib for the 85 amp alternator and V belts for the other stuff. If you listen to a GQ Patrol you will often hear belt slip and they have 2 V belts running their 120 amp alternator.
My first alternator was an 85 amp Bosch and the second an 85 amp Ingram.

Short of changing the whole front of the engine IMHO the 2 alternators are the best sytem.

Is this a record for a late reply???

Regards Philip A

[oztrax]

ok done my dual Alt on a d1 tdi 300

little legs u got any pics of yours you could post ?

oz

[oztrax]

Thanks PhilA, you were spoton with the charge light scenario.
I read your hint just before i completed 2nd alt and battery install
on my TDI 300 D1

BTW how does the relay tie between batts go with your fridge ?

with the 12.5 VDC cutout how many hours approx for the engel ?

Alternator on the TDI 300 D1 kicks out 60 amps normally at night and about 40 amps in day with aircon on. So adding another battery would really load it up.

regards
OZ

[PhilipA]

I have now sold the RRC and have a Disco 2 TD5.
I have a straight forward ABR controllerr which cuts at 12.4 volts. the one from the RRC LOL. With my 750 cca Optima and 130AH AGM I had 11.98 v in the AGM after about 40hours in hot weather
The RRC system would not be as good probably , but would have been up there.
It really depends on the size of the batteries, the age, and just how hot it is. In Kakadu my RRC system before the link lasted only about 24 hours but it never got under about 25 c at night.
But anything you can do to increase battery capacity must have a positive effect.
regards Philip :cool:;)