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bgredjeep
06-07-2015, 10:53 PM
Hey guys, I'm looking for info/suggestions on wiring my battery in the Jeep. I'm moving the battery to the rear and adding a cutoff switch between the seats. So far I've got a switch, and awaiting delivery of 20' of 2 gauge cable, a junction box, and mil spec terminals.

The info I've found indicates I should install the switch between the battery and starter solenoid, and run the alternator direct to the battery side of the switch. I'm also adding a blue sea fuse panel for accessories that will be on the cutoff. The only item I'm planning to bypass the cutoff is the computer so I'm not constantly wiping the memory.

One item I'm not sure about is the winch wiring. I've always read you should wire the winch direct to the battery (and done so). I also don't want to run that load through the switch (it's rated for 300amps cont.). Do I need to run the winch wires direct? I'm OK doing so, it just seems like I'll have a bunch of big cables running through the Jeep. I want to do the cleanest, correct way so I don't cause any issues.

Anyone with a rear mounted battery please lmk how yours is setup. Any other related suggestions are welcome.

RClippa
06-08-2015, 07:39 AM
What is your reasoning for a cutoff switch? If the winch, computer, and alternator aren't being cutoff is it really doing much for you?

My last rear battery setup was built with a BMW3 series battery cable from the junkyard and no switch. That cable just ran from the back to the front. They have a little post on the end that is just like a battery terminal so I could clamp the original cable directly to that. Bonus is that this gives you a great jump-start post as well.

There aren't any affordable switches that will handle the winch. There are some switches made for newer motors that have a wire for the alternator excitation wire that will actually shut your whole vehicle down when you turn it off. Normal cut off switches won't do this. This is important if in cases that you get a short on your positive to frame. The cut off switch will shut down not only the battery but the 100+ amps from your alternator. Only downside is if this short is on your winch cable because you can't switch that due to the stall current of the motor.

bgredjeep
06-08-2015, 08:48 AM
I want to cut power to things that might start or feed a fire (fuel pump), and any electronics that might drain the battery. I don't know about the rest. I think my switch could handle winching a few mins at a time, but I generally don't like pushing things like this to max capacity ratings. The way I was planning to run the alternator would only connect it to the battery. The switch would cut ignition and accessory power.

This link has the wiring diagram I was looking at for the switch (post 9). This doesn't account for the winch and I couldn't find one that does.

http://ls1tech.com/forums/conversions-hybrids/1254252-alternator-battery-disconnect.html

Here's the spec for the switch. It's a Blue Sea m series 6006.


• Continuous Rating: 300 Amps
• Terminal Stud Torque: 120 in-lb maximum
• Cable Clearance for 4/0 AWG Cables: 1.12"
• Cranking Rating @ 10 sec: 1,500 Amps
• Cranking Rating @ 1 min: 775 Amps
• Intermittent Rating (5 min.): 500 Amps
• Maximum Voltage Rating: 48V DC

bgredjeep
06-08-2015, 08:54 AM
Here's a pic similar to the other diagram I referenced.

http://ls1tech.com/forums/attachments/drag-racing-tech/8223d1084255628-couple-battery-box-kill-switch-qs-battery_relocation_zed2.jpg

Twilliamson
06-08-2015, 11:06 AM
Rather than a disconnect switch, you could use a Solenoid and have a kill switch (standard size toggles) setup that would disconnect the power from the battery. You could use one for vehicle equipment and one for winch. the only downside is they draw alot of current to keep the contacts pulled in (1amp each). Worst Case on the winch solenoid is that the contacts weld and you have to tap it with a hammer to free them, but i highly doubt that would ever happen.

http://williamsonwebsolutions.com/share/images/orscdrawin.png

http://www.amazon.com/gp/product/B000CEBXRS/ref=pd_lpo_sbs_dp_ss_3?pf_rd_p=1944687522&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B009GKAGMM&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1TQ0QNQKJF73FP7X8A52

Twilliamson
06-08-2015, 11:14 AM
Here's a pic similar to the other diagram I referenced.



The problem i see with this is if something happens in the heavy guage wire between your battery and your alternator, you have a 1/0 gauge fuse that isn't going to blow until it burns to the ground....You could fuse it 150/300 amp inline fuse would work.

bgredjeep
06-08-2015, 11:58 AM
The problem i see with this is if something happens in the heavy guage wire between your battery and your alternator, you have a 1/0 gauge fuse that isn't going to blow until it burns to the ground....You could fuse it 150/300 amp inline fuse would work.

Yeah, the diagram shows a fuse on that line. That portion is no different than it would be if I didn't wire a switch.

The 2 differences between what I'm looking to do, vs what is already in the jeep are the battery location being 8' (of cable) further away, and the alternator being wired on the non-cutoff side of the switch.

My current switch is directly on the battery. I don't know if it's right, wrong, better or worse one way or the other. The good news is that I probably won't have all the wire and fuse holders I've ordered for a week or 2 so plenty of time to figure it out.

RClippa
06-08-2015, 12:03 PM
Here's a pic similar to the other diagram I referenced.

http://ls1tech.com/forums/attachments/drag-racing-tech/8223d1084255628-couple-battery-box-kill-switch-qs-battery_relocation_zed2.jpg

This one will shut the vehicle down when you turn off the switch. It disconnects the alternator from the system. IMO this is what you want. You remove all power from the vehicle and the fuel pump can't feed the fire. The main problem comes in with the ability for the cables themselves to feed the fire. Electrical fires are nasty and generate lots of heat. Initially more so than a fuel based fire. The battery disconnect is just the first defense for something like that. You would still want fuel cut-offs because they can still lead to siphon conditions that will continue to feed the flames. Multiple fire extinguishers is also needed.

It is not unheard of for a 9000lb winch to pull 1000+amps for a little while winching. Sadly it can do this more than you would think when everything is in motion and the rig slides back down against the rope. We use Gigavac contactors at work to handle large amperage loads. I would love to put one on the rig, but the price is not friendly.

bgredjeep
06-08-2015, 12:08 PM
Rather than a disconnect switch, you could use a Solenoid and have a kill switch (standard size toggles) setup that would disconnect the power from the battery. You could use one for vehicle equipment and one for winch. the only downside is they draw alot of current to keep the contacts pulled in (1amp each). Worst Case on the winch solenoid is that the contacts weld and you have to tap it with a hammer to free them, but i highly doubt that would ever happen.

http://williamsonwebsolutions.com/share/images/orscdrawin.png


http://www.amazon.com/gp/product/B000CEBXRS/ref=pd_lpo_sbs_dp_ss_3?pf_rd_p=1944687522&pf_rd_s=lpo-top-stripe-1&pf_rd_t=201&pf_rd_i=B009GKAGMM&pf_rd_m=ATVPDKIKX0DER&pf_rd_r=1TQ0QNQKJF73FP7X8A52

I don't think those relays would handle winch loads for long, if at all, and it really wouldt change anything with the main wire runs I'd need. A big, easy to reach, manual switch mounted to the cage between my seats will be fine for that portion.

TCBronco
06-08-2015, 12:45 PM
Hey guys, I'm looking for info/suggestions on wiring my battery in the Jeep. I'm moving the battery to the rear and adding a cutoff switch between the seats. So far I've got a switch, and awaiting delivery of 20' of 2 gauge cable, a junction box, and mil spec terminals.

The info I've found indicates I should install the switch between the battery and starter solenoid, and run the alternator direct to the battery side of the switch. I'm also adding a blue sea fuse panel for accessories that will be on the cutoff. The only item I'm planning to bypass the cutoff is the computer so I'm not constantly wiping the memory.

One item I'm not sure about is the winch wiring. I've always read you should wire the winch direct to the battery (and done so). I also don't want to run that load through the switch (it's rated for 300amps cont.). Do I need to run the winch wires direct? I'm OK doing so, it just seems like I'll have a bunch of big cables running through the Jeep. I want to do the cleanest, correct way so I don't cause any issues.

Anyone with a rear mounted battery please lmk how yours is setup. Any other related suggestions are welcome.

Thats basically how I have mine ran. Battery is in the back with a cut off switch under the dash that cuts everything but the keep alive power for the computer. I also have another set of cables ran all the way to the back for the winch. I recently installed the winch but the cut off switch has been on there for many years with no problems.

Twilliamson
06-08-2015, 01:41 PM
I don't think those relays would handle winch loads for long, if at all, and it really wouldt change anything with the main wire runs I'd need. A big, easy to reach, manual switch mounted to the cage between my seats will be fine for that portion.

I don't agree. A winch uses much smaller contactors/solenoids. You wouldn't be switching the disconnect coil under load, As long as the contacts are in good shape (contact resistance less than .5 ohm) you would never see any problems with a large solenoid such as the one I sent earlier. This also applies to your vehicle starter solenoid, they too are much smaller than the one i previously sent. I have seen this type used as starter solenoids on Semi before...
(The patent i was just awarded was around relays and contact deterioration, i have hundreds of hours in the lab studying loads and switching them with relays).

With that said. Properly fused circuits should be more than enough to keep a rig safe. A Master disconnect IMO should be just that.. Disconnected at the battery and everything is powered down and safe. Winches always make me nervous, because there is no protection available if something goes wrong, your rig will burn.

Another thing to keep in mind is the quality of crimps and technique used to connect those. If they are are not proper you will get some amount of resistance in the terminal. This is probably the biggest failure point i see in heavy AC applications, where someone didn't properly terminate a cable and it heated before burning.

As for the mains wires. You COULD place the solenoids under the hood, it would be more resistance to the battery but closer to the alternator when your winching. The game you play here is every inch of wire is more resistance, more resistance is lower voltage and heat generated.

bgredjeep
06-08-2015, 08:43 PM
A winch uses a series of solenoids to handle the load, not a single solenoid. Starter solenoids are momentary and certainly pull nothing like what a winch will do under load.

At the end of the day, that's just adding more moving parts and that's not my aim here. I'll take a 300 amp rated manual switch over a 200 amp rated solenoid. I don't trust the 300 amp switch to be capable of handling the winch load either.

RClippa
06-09-2015, 07:25 AM
The winch actually only uses solenoids to reverse the polarity to the motor to spin both directions. All of the current still flows through a single solenoid. That said I wouldn't add solenoids to do what you want. I would wire it up so that the battery disconnect kills everything but the winch. I think you are just out of luck of putting that on the switch. I would let it kill the alternator, computer, fuel pump. Everything. It isn't a shutdown for the vehicle except when **** hits the fan or you store it. No reason to worry about the ecu memory. Relearn is fast and doesn't hurt anything.

Steve97tj
06-09-2015, 07:56 AM
Good tech thread. Electrical is foreign to me and I've been wanting to learn more.


Sent from my iPhone using Tapatalk

Twilliamson
06-09-2015, 08:41 AM
The winch actually only uses solenoids to reverse the polarity to the motor to spin both directions. All of the current still flows through a single solenoid. That said I wouldn't add solenoids to do what you want. I would wire it up so that the battery disconnect kills everything but the winch. I think you are just out of luck of putting that on the switch. I would let it kill the alternator, computer, fuel pump. Everything. It isn't a shutdown for the vehicle except when **** hits the fan or you store it. No reason to worry about the ecu memory. Relearn is fast and doesn't hurt anything.

Right, The Winch does use series solenoids, and all the current still flows through a single solenoid. If anyone is interested in learning exactly what happens when you power in or out a winch, this Wikipedia article is pretty good. H-Bridge (http://en.wikipedia.org/wiki/H_bridge) .

Also, Wanted to clarify I was only giving my opinion (and background) on the situation. I didn't want to come across as one of those internet trolls....

RClippa
06-09-2015, 10:00 AM
Right, The Winch does use series solenoids, and all the current still flows through a single solenoid. If anyone is interested in learning exactly what happens when you power in or out a winch, this Wikipedia article is pretty good. H-Bridge (http://en.wikipedia.org/wiki/H_bridge) .

Also, Wanted to clarify I was only giving my opinion (and background) on the situation. I didn't want to come across as one of those internet trolls....

Tripp you are totally trolling. I didn't realize that you did a bunch of work with contactors and relays. I spend a lot of time blowing them up. I guess charging an electric vehicle at 1000 amps and opening contactors is not what they are really designed for. Things get fun when you send a 2-10hz actuation signal while charging at 1000 amps. Got to love durability/reliability testing.

Twilliamson
06-09-2015, 11:43 AM
Tripp you are totally trolling. I didn't realize that you did a bunch of work with contactors and relays. I spend a lot of time blowing them up. I guess charging an electric vehicle at 1000 amps and opening contactors is not what they are really designed for. Things get fun when you send a 2-10hz actuation signal while charging at 1000 amps. Got to love durability/reliability testing.

Yup... I actually have a (co inventor) patent (https://www.google.com/patents/US8884532?dq=ripley+lighting+controls&hl=en&sa=X&ei=yAh3VcCLLdSyyASWu4KwAQ&sqi=2&pjf=1&ved=0CCUQ6AEwAQ)on freeing welded contacts on a relay.... Yeah, My background is switching 1000Watt (steady state) loads, not 1000 amps in street and area lighting ... but theory still applies.
No current No arc, once the contacts close resistanced should be low enough to not affect overall opperation.

meaders
06-09-2015, 03:56 PM
when ya'll are talking about the winch solenoids not sharing the load are you talking about a 4 solenoid control pack for series wound motors (3 post motors) or two solenoid control packs for permanent magnet motors (two post motors)?