Adding extra slave end

[hedelta]

Thinking on adding a slave receptacle to the rear of the 1009. I would like to just extend the wires from the radio bus bar. My question is, is the wire too small to do this? Or anything else that woulk prevent me from doing this? Thanks for your time.

Sean

 

[doghead]

What do you plan to use it for?

 

[cucvrus]

I will assume that you would like to have an extra slave receptacle on the rear. I have seen it done before. Just use the same gauge wire that is running from the buss bar to the front slave receptacle. I would think after that the size of the 5/16" buss bar studs would not be able to increase the amperage or feed a heavier cable. But just run them back on the right inside frame flange and loom them and secure them up away from heat and other moving parts. Good Luck. That is all I ever seen done.

 

[Bunkerbuilder]

Its not cheap but when i did this i used stainless steel hydraulic tubing to encase the wire in and used 4/0 cables.

 

[hedelta]

I plan on using it for MRE heater, impact and of course when im too lazy to turn the truck around use it to slave my or another persons vehicle.

 

[doghead]

Should work ok.

Jumping other vehicles with your 1009 might not perform quite as well though.

 

[Bunkerbuilder]

This is why I went with 4/0 pos and neg wires down the frame rail.
ETA: I branched off the firewall binding posts area as my beasty is a M1028.

Should work ok.

Jumping other vehicles with your 1009 might not perform quite as well though.

 

[Csm Davis]

I would use a 4/0 positive cable straight to the positive terminal on the batteries and a short 4/0 negative cable to the frame, If you plan on using it for jump starting operations.

 

[skysix]

Why 4/0 instead of 2/0 like the 20' slave cable uses? $9.46 a foot for 0000 is a lot of coin to spend. http://www.grainger.com/product/CAROL-4-0-AWG-Welding-Cable-1UGT7

Or did you mean No. 4 / 4 gauge etc. That has an capacity of 100amps for up to 75' 4/0 gives you between 550 and 600 amps (depending on insulation type) for 50' (2/0 400-450A)

Here is an analysis of a 1000 amp load (electric car) and 2/0 is as good as 4/0 in that application. http://heaa.info/wp-content/uploads/library/2_0_vs_4_0.pdf

 

[Csm Davis]

Why 4/0 instead of 2/0 like the 20' slave cable uses? $9.46 a foot for 0000 is a lot of coin to spend. http://www.grainger.com/product/CAROL-4-0-AWG-Welding-Cable-1UGT7

Or did you mean No. 4 / 4 gauge etc. That has an capacity of 100amps for up to 75' 4/0 gives you between 550 and 600 amps (depending on insulation type) for 50' (2/0 400-450A)

Here is an analysis of a 1000 amp load (electric car) and 2/0 is as good as 4/0 in that application. http://heaa.info/wp-content/uploads/library/2_0_vs_4_0.pdf

Okay so first yes I mean 4/0 if you are going to be jumping off other vehicles. As can tell you from slave starting more trucks than I care to remember, probably around 3000 at this point, slave cables are just barely big enough they get hot quickly so being bigger will help because at this point you are going 50' give or take and you want as much amperage as possible to get to the dead vehicle. Also I have a set of 50' slave cables and they will not carry enough amperage to do the job many times. Also within reason larger is better in a DC motor circuit. You can use a smaller cable but it will not work as well.
Also just looked and you can get it for $5.00 or less in red even and I wouldn't run a truck length ground, just use the frame.

 

[cucvrus]

Doesn't the plumbing theory come into effect here? It will not matter on the size of the cables if you are hooking them up to a small diameter stud. As in a CUCV. It has 5/16" studs on the firewall buss bar. It will only be able to hold so much of a load. So if I add bigger cables to the 5/16" studs then they can handle I am just making them the weakest link in the circuit. Its like having the 2 1/4" - 2 1/2" exhaust manifolds and running bigger pipe to the back of the truck and thinking you just improved the exhaust system. You are still getting what is coming thru the smallest point of any system at the end. Correct me if I am wrong.

 

[73m819]

This goes along with this thread though it is a 5t mod, I mounted a second slave port in the lower left corner of my m819s grill and a second slave port in the left fender, right by the step on Swiss's m923, I am SURPRISED how much both of those ports have been used slaving off other trucks. This has proved so handy that Swiss's m62 is on the to do LIST for a left side slave port as well,

 

[Keith_J]

Doesn't the plumbing theory come into effect here? It will not matter on the size of the cables if you are hooking them up to a small diameter stud. As in a CUCV. It has 5/16" studs on the firewall buss bar. It will only be able to hold so much of a load. So if I add bigger cables to the 5/16" studs then they can handle I am just making them the weakest link in the circuit. Its like having the 2 1/4" - 2 1/2" exhaust manifolds and running bigger pipe to the back of the truck and thinking you just improved the exhaust system. You are still getting what is coming thru the smallest point of any system at the end. Correct me if I am wrong.

Not really. You can run a few hundred amps through those connections, it is the length and gauge of the jumper wire that limits current.

a few years back at our museum, we were trying to jump start one of the M4s using 50 foot slave cables, no go. Moved a CUCV into the museum so 25 foot cables would reach and it fired right up. That was my idea...

likewise, under the national electric code, running 100 amps through #8 wire isn't kosher yet that is what the alternators on a CUCV are wired with because it is a short run. There is a good drop in voltage when running that much current.

 

[Recovry4x4]

When the glut of HMMWV slave receptacles hit the market, I did the same on a deuce. The cables were the perfect length.

 

[hedelta]

So basically I should just run larger wires to the bus bar install a larger bus bar then continue on to where I will install the new slave port.

 

[doghead]

That would be better, if jumping bigger trucks is important to you.

 

[Bunkerbuilder]

This is the way I see it.
Keep in mind its not the 5/16 stud on the bussbar that links the wires together alone its the samwich of the bussbar and the cable lug and or the two cable lugs if you are stacking them on one stud.

Doesn't the plumbing theory come into effect here? It will not matter on the size of the cables if you are hooking them up to a small diameter stud. As in a CUCV. It has 5/16" studs on the firewall buss bar. It will only be able to hold so much of a load. So if I add bigger cables to the 5/16" studs then they can handle I am just making them the weakest link in the circuit. Its like having the 2 1/4" - 2 1/2" exhaust manifolds and running bigger pipe to the back of the truck and thinking you just improved the exhaust system. You are still getting what is coming thru the smallest point of any system at the end. Correct me if I am wrong.

 

[Csm Davis]

Doesn't the plumbing theory come into effect here? It will not matter on the size of the cables if you are hooking them up to a small diameter stud. As in a CUCV. It has 5/16" studs on the firewall buss bar. It will only be able to hold so much of a load. So if I add bigger cables to the 5/16" studs then they can handle I am just making them the weakest link in the circuit. Its like having the 2 1/4" - 2 1/2" exhaust manifolds and running bigger pipe to the back of the truck and thinking you just improved the exhaust system. You are still getting what is coming thru the smallest point of any system at the end. Correct me if I am wrong.

You are correct in theory but are not seeing the connection on the buss bar correctly, it isn't just the stud that takes the load.

So basically I should just run larger wires to the bus bar install a larger bus bar then continue on to where I will install the new slave port.

Don't run the slave plugs off of the buss bar, that is extra connections that are not needed run them directly to the batteries. With a military terminal on a post battery there is plenty of room to attach three lugs, one front slave, one rear slave, one to the truck.

This is the way I see it.
Keep in mind its not the 5/16 stud on the bussbar that links the wires together alone its the samwich of the bussbar and the cable lug and or the two cable lugs if you are stacking them on one stud.

This is correct you have the surface area of both sides and what little is touching the threads. The buss bar is more for distribution than full amperage load which should be pulled directly from the batteries.

 

[Skinny]

In theory yes and I agree, going directly to the batts is typically the best approach but being that the distance from the battery to the bus bar is small and the cable is pretty robust, has anyone actually run the numbers or performed a voltage drop to see if they are the limiting factor? Sure jumping a truck is a serious load but we are talking for such short bursts and short distances I would hesitate to say this is going to end in failure. Has anyone actually added a rear slave connected to the bus bar and experienced extreme voltage drop or hot connections during use?