Just use the 7 pin to wire your trailer, it has a battery charge connection. All you are doing is charging the battery that supplies the winch.
Adding electrical connector
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Adding electrical connector
I pull a small car trailer thats got a winch on it and Im going to wire it so the truck charges the winch battery.Im going to use Anderson 50 amp connectors with 6ga wire.My question is should I put a fuse in this circuit somewhere?Has anyone here done this if so howd you hook up to the trucks batteries?I want to do it without cutting any wires or having to butcher anything.
Post Fiend
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Can you tell me how much is the power load you are adding?
What size alternator do you have? What make? OEM? Replacement? specifics please.
What accessories above stock that are additional on the truck now?
Q: do you even have excess power?
What size alternator do you have? What make? OEM? Replacement? specifics please.
What accessories above stock that are additional on the truck now?
Q: do you even have excess power?
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I honestly dont know how much load the battery will be,its for maintaining it,def not charging from dead.
I put in a 140amp Motorcraft alt.
No additional accessories added on.
I cant say Ive got excess power.
Ive heard of people doing this,but never asked questions on the specifics of how they went about it.
I put in a 140amp Motorcraft alt.
No additional accessories added on.
I cant say Ive got excess power.
Ive heard of people doing this,but never asked questions on the specifics of how they went about it.
Post Fiend
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Did you put on a Motorcraft OEM 140amp diesel alternator or the car grade part?
This is critical --- if it is the car grade part, it will die --- you don't have enough capacity.
If you have a diesel truck grade 140amp alternator, there is enough to play around with.
Tell me the size / capacity of the batteries back there.
Amp hours, etc.
This is critical --- if it is the car grade part, it will die --- you don't have enough capacity.
If you have a diesel truck grade 140amp alternator, there is enough to play around with.
Tell me the size / capacity of the batteries back there.
Amp hours, etc.
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Thx for the welcome Max.The trailer Ive got uses a sealed harness and I didnt want to cut into it,but I really need to take a close look at it,to see if it has that wire in the harness.Appreciate the diagram tho!
Gearloose,its the diesel alt.Off the top of my head I think the batt is roughly 765 cca,and anything more than that I do not know.
Appreciate all the instant help.
Think I may call the trailer manufacturer and see what they recommend.
Gearloose,its the diesel alt.Off the top of my head I think the batt is roughly 765 cca,and anything more than that I do not know.
Appreciate all the instant help.
Think I may call the trailer manufacturer and see what they recommend.
Hotshot
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From: Middle Tn.
Side note, whenever you add a circuit always, always make sure it is protected. Beats burning down the truck or melting your electronics.
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Post Fiend
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If you have the proper diesel alternator, and you are only running one extra battery, it is fine.
I would always charge it up full (and only use the trailer plug extra) to maintain charge or replace what little I used on a job -- but not as the regular charger.
(I am crazy about safety margins).
CCA is not a good measure for a deep discharge battery (if that is what you use it for)... that is rated by amp hours (xxxx amps for xxx hours).
Here is the scoop on flooded cell lead acid battery charging:
LEAD ACID BATTERY CHARGING INFORMATION, BATTERY TYPES AND OPERATION - SOLAR NAVIGATOR WORLD ELECTRIC NAVIGATION CHALLENGE, NELSON KRUSCHANDL, BLUEBIRD ELECTRIC LAND SPEED RECORD CARS
You are pretty safe --- it sounds like you are using a spare truck battery.
People pretty commonly have 2 deep cycle batteries in their trailers, and use the truck alternator to charge them up.
140amp should be ample.
I would always charge it up full (and only use the trailer plug extra) to maintain charge or replace what little I used on a job -- but not as the regular charger.
(I am crazy about safety margins).
CCA is not a good measure for a deep discharge battery (if that is what you use it for)... that is rated by amp hours (xxxx amps for xxx hours).
Here is the scoop on flooded cell lead acid battery charging:
Battery Charging Voltages and Currents:
Most flooded batteries should be charged at no more than the "C/8" rate for any sustained period. "C/8" is the battery capacity at the 20-hour rate divided by 8. For a 220 AH battery, this would equal 26 Amps. Gelled cells should be charged at no more than the C/20 rate, or 5% of their amp-hour capacity. The Concorde AGM batteries are a special case - the can be charged at up the the Cx4 rate, or 400% of the capacity for the bulk charge cycle. However, since very few battery cables can take that much current, we don't recommend you try this at home. To avoid cable overheating, you should stick to C/4 or less.
Charging at 15.5 volts will give you a 100% charge on Lead-Acid batteries. Once the charging voltage reaches 2.583 volts per cell, charging should stop or be reduced to a trickle charge. Note that flooded batteries MUST bubble (gas) somewhat to insure a full charge, and to mix the electrolyte. Float voltage for Lead-Acid batteries should be about 2.15 to 2.23 volts per cell, or about 12.9-13.4 volts for a 12 volt battery. At higher temperatures (over 85 degrees F) this should be reduced to about 2.10 volts per cell.
Most flooded batteries should be charged at no more than the "C/8" rate for any sustained period. "C/8" is the battery capacity at the 20-hour rate divided by 8. For a 220 AH battery, this would equal 26 Amps. Gelled cells should be charged at no more than the C/20 rate, or 5% of their amp-hour capacity. The Concorde AGM batteries are a special case - the can be charged at up the the Cx4 rate, or 400% of the capacity for the bulk charge cycle. However, since very few battery cables can take that much current, we don't recommend you try this at home. To avoid cable overheating, you should stick to C/4 or less.
Charging at 15.5 volts will give you a 100% charge on Lead-Acid batteries. Once the charging voltage reaches 2.583 volts per cell, charging should stop or be reduced to a trickle charge. Note that flooded batteries MUST bubble (gas) somewhat to insure a full charge, and to mix the electrolyte. Float voltage for Lead-Acid batteries should be about 2.15 to 2.23 volts per cell, or about 12.9-13.4 volts for a 12 volt battery. At higher temperatures (over 85 degrees F) this should be reduced to about 2.10 volts per cell.
You are pretty safe --- it sounds like you are using a spare truck battery.
People pretty commonly have 2 deep cycle batteries in their trailers, and use the truck alternator to charge them up.
140amp should be ample.
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Post Fiend
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Thx for the welcome Max.The trailer Ive got uses a sealed harness and I didnt want to cut into it,but I really need to take a close look at it,to see if it has that wire in the harness.Appreciate the diagram tho!
Think I may call the trailer manufacturer and see what they recommend.
Think I may call the trailer manufacturer and see what they recommend.
The junction box is where you tap in. Must be a fuse immediately after the tap ---or a fusible link.
Whenever you go through a panel / body / floor, there must be grommets to prevent rubbing / damage to wires.
Also --- strain reliefs to prevent wire from being pulled.
Be incredibly careful re vibration / rubbing chafing damage over time --- even with a great install, inspect regularly.
Do not bypass fuses --- if it blows check root causes.
Do not cut into the harness on the outside!
Whatever you do, multiple fuses!!!
Fuse it once at the junction box tap in, fuse it again before the battery with a smaller one --- so the little one blows first (saving you crawling down to replace the bigger one).
Be sure your batteries are securely tied down, and in a acid resistant / proof battery box VENTILATED to outside. with a proper, approved battery vent.
Hydrogen can build in an enclosed space, and explode.
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This trailer has no junction box.Everything comes out out the cable.Hard to explain but I'll try.Starting at the hitch the harness goes back to the axles where the harness has a connector in it.Out of this comes the wires for the electric brakes, wires to charge the electric brake battery,and front half lighting.The other half of the connector steps down size wise and goes back to the rear lights.
I wont ever cut a harness.I dont know much about electrical but I do know doing that opens up a world of issues.Ive seen too many idiots do that to cars and make a real mess.
I wont ever cut a harness.I dont know much about electrical but I do know doing that opens up a world of issues.Ive seen too many idiots do that to cars and make a real mess.
Post Fiend
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Look for the power cable at the end where it comes out.
If you can pull it clear of the cable sheath... use a crimp connector (be sure to protect it against rust), attach a fuse right there and then you can extend it...
Assuming that the cable is hooked up at the other end of the plug -- You can test with a VOM first.
If you can pull it clear of the cable sheath... use a crimp connector (be sure to protect it against rust), attach a fuse right there and then you can extend it...
Assuming that the cable is hooked up at the other end of the plug -- You can test with a VOM first.
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