How To - Doing Alternator to Battery Charge
- Thread starter cortttt
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Whatever you do do not use a diode based battery isolator. Check out the below link. Good stuff. Stinger makes a 200a for a lot less $$.
http://www.colehersee.com/home/grid/cat/212/
I would suggest DIY unless you find a shop that is totally into high quality work. The vast majority of isolator systems that I have seen have been total cheese...
http://www.colehersee.com/home/grid/cat/212/
I would suggest DIY unless you find a shop that is totally into high quality work. The vast majority of isolator systems that I have seen have been total cheese...
highdesertranger
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I don't know how to do schematics so I will try to explain, it's actually really easy.
you will need,
1. a good continuous duty solenoid.
2. enough good quality heavy copper wire to go from the alternator to the solenoid, and from the solenoid to the battery. the thicker the wire the better. I would go with at least 6gauge. do not use household wire.
3. 14gauge wire to energize the solenoid.
4. good quality terminals to make all the connections.
then you just hook it all up.
1. run your wire from the alternator batt+ terminal to one side of the solenoid. note this wire can take power from battery + terminal also, but the alternator is better.
2. run your other cable to your house battery.
3. run your 14gauge cable from a hot ignition terminal on the fuse box,(there should be several) to the small terminal of the solenoid.
and that's it in a nut shell. feel free to ask any questions. highdesertranger
you will need,
1. a good continuous duty solenoid.
2. enough good quality heavy copper wire to go from the alternator to the solenoid, and from the solenoid to the battery. the thicker the wire the better. I would go with at least 6gauge. do not use household wire.
3. 14gauge wire to energize the solenoid.
4. good quality terminals to make all the connections.
then you just hook it all up.
1. run your wire from the alternator batt+ terminal to one side of the solenoid. note this wire can take power from battery + terminal also, but the alternator is better.
2. run your other cable to your house battery.
3. run your 14gauge cable from a hot ignition terminal on the fuse box,(there should be several) to the small terminal of the solenoid.
and that's it in a nut shell. feel free to ask any questions. highdesertranger
highdesertranger
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yes you can use the frame for the house battery negative. I assumed the house battery was already in place. they only asked for the battery charge circuit. highdesertranger
SternWake
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House battery to frame grounds need to be done well as they are problematic over time, yet can appear fine and dandy from the exterior. Think about a thick walled ring terminal under a 1/2-20 or even finer machined thread tightened to 75Lb/ft then covered with a thick grease or perhaps a rubberized undercoating or plastidip for a good solid long lasting ground path. For additional alternator contribution to depleted house battery, Add another ground cable between frame and alternator mounting bolt or (-) stud on Alternator itself. Account for engine flex within engine bay.
For maximum alternator contribution a thick copper path right back to alternator (-) stud or mounting bolt is best, but thick copper is $$ and the benefits over a solid well prepped frame ground are perhaps not worth it.
Some people freak out over the thought of tapping a circuit in their fuse box to activate the solenoid.
http://www.amazon.com/Wirthco-30200-Fuse-Tap-Kits/dp/B000CQDRSE
http://www.amazon.com/Radar-Mount-D...=UTF8&qid=1455338711&sr=1-7&keywords=fuse+tap
With the above products, finding an appropriate circuit to tap requires a voltmeter/ digital multimeter. Best to find one that is live after engine starts and not live during engine cranking. Check Hvac blower motor circuit as usually power is cut to blower motor during engine cranking.
I just found a factory 12v engine on wire under my dashboard, so that is an option.
There are voltage sensing solenoids like the Surepower 1314 and 1315, and the Blueseas ACR, if one wants nothing to do with taping a circuit to trigger the dumb/simple continuous duty solenoid. I'm not keen on 'dual sense' smart solenoids when there is Solar involved.
The Simple solenoid is cheapest automatic way to accomplish the task.
Here is an Okay write up on the process.
http://www.expeditionportal.com/for...ke-a-cheap-isolated-dual-battery-setup-for-50
The diagrams in that link showpower being taken solenoid/house battery from engine battery. This places additional load on the original charge path, with the house batteries tacked onto the end of the too thin circuit. The OEM cable was barely adequate just to recharge the already nearly fully charged engine battery and power all vehicle loads, certainly not to recharge a pair of depleted batteries.
If one Instead takes power from the alternator(+) stud right to solenoid, the circuit is shorter and parallel to the stock circuit, and more recharging will occur at lower states of charge when the battery is thirsty and can accept huge recharge currents. Also there is a better chance the voltage regulator will allow higher voltages to be held for longer, compared to if the engine battery is directly in the path from alternator to house battery, Translation, more charging in the same amount of driving, but at the expense of alternator life as it will run hotter when asked for more output by a hungry depleted battery(s).
Expensive to replace alternators can be wired to solenoid/house battery with thinner cable to intentionally limit what the depleted house battery can ask for. 8 awg is as thin as I would recommend. 10awg is too thin when the battery is low. Charging will be significantly attenuated with 10awg or thinner at the distances likely to occur in such a setup.
No sense killing an 800$ alternator trying to prolong the life of a 200 dollar battery.
Protecting cabling, especially if run under body, inside split loom tubing is wise.
Quality Zip ties are your friends.
So are these:
http://www.amazon.com/Allstar-Perfo...sim_200_4?ie=UTF8&refRID=1CF47KSZ0J45ZJSWQMEV.
For maximum alternator contribution a thick copper path right back to alternator (-) stud or mounting bolt is best, but thick copper is $$ and the benefits over a solid well prepped frame ground are perhaps not worth it.
Some people freak out over the thought of tapping a circuit in their fuse box to activate the solenoid.
http://www.amazon.com/Wirthco-30200-Fuse-Tap-Kits/dp/B000CQDRSE
http://www.amazon.com/Radar-Mount-D...=UTF8&qid=1455338711&sr=1-7&keywords=fuse+tap
With the above products, finding an appropriate circuit to tap requires a voltmeter/ digital multimeter. Best to find one that is live after engine starts and not live during engine cranking. Check Hvac blower motor circuit as usually power is cut to blower motor during engine cranking.
I just found a factory 12v engine on wire under my dashboard, so that is an option.
There are voltage sensing solenoids like the Surepower 1314 and 1315, and the Blueseas ACR, if one wants nothing to do with taping a circuit to trigger the dumb/simple continuous duty solenoid. I'm not keen on 'dual sense' smart solenoids when there is Solar involved.
The Simple solenoid is cheapest automatic way to accomplish the task.
Here is an Okay write up on the process.
http://www.expeditionportal.com/for...ke-a-cheap-isolated-dual-battery-setup-for-50
The diagrams in that link showpower being taken solenoid/house battery from engine battery. This places additional load on the original charge path, with the house batteries tacked onto the end of the too thin circuit. The OEM cable was barely adequate just to recharge the already nearly fully charged engine battery and power all vehicle loads, certainly not to recharge a pair of depleted batteries.
If one Instead takes power from the alternator(+) stud right to solenoid, the circuit is shorter and parallel to the stock circuit, and more recharging will occur at lower states of charge when the battery is thirsty and can accept huge recharge currents. Also there is a better chance the voltage regulator will allow higher voltages to be held for longer, compared to if the engine battery is directly in the path from alternator to house battery, Translation, more charging in the same amount of driving, but at the expense of alternator life as it will run hotter when asked for more output by a hungry depleted battery(s).
Expensive to replace alternators can be wired to solenoid/house battery with thinner cable to intentionally limit what the depleted house battery can ask for. 8 awg is as thin as I would recommend. 10awg is too thin when the battery is low. Charging will be significantly attenuated with 10awg or thinner at the distances likely to occur in such a setup.
No sense killing an 800$ alternator trying to prolong the life of a 200 dollar battery.
Protecting cabling, especially if run under body, inside split loom tubing is wise.
Quality Zip ties are your friends.
So are these:
http://www.amazon.com/Allstar-Perfo...sim_200_4?ie=UTF8&refRID=1CF47KSZ0J45ZJSWQMEV.
Let's not forget that one should have fuses or non-self resetting dc breakers very close to EACH end of the positive cable that charges the house battery from the alternator or positive terminal of the starting battery.
