Battery Cable Upgrade and Pricing

Topic: Battery Cable Upgrade and Pricing (Read 1912 times) previous topic - next topic

Re: Battery Cable Upgrade and Pricing

Reply #25 – February 14, 2016, 11:39:36 pm

Update on my busbar project:

Finally got my 4" x 8" x 1/2" bar cut into two 2" x 8" x 1/2" bars. It ain't pretty, and was a lot more difficult than I imagined. (Kinda reminds me of the $1000 I am saving by installing my AutoMotion shades myself.

) I started out trying to cut it by hand with a hack saw, but without a vice, I had a hard time holding it in position while I cut; and it was taking forever! Decided to try my sawsall with a wide metal cutting blade. It did okay until I got past the halfway point. I did not have a vise available and was trying to use a Black and Decker Workmate, but it wasn't up to the task.

Eventually started a new cut from the other end, with expected gross job of lining up the two cuts. Cleaned it up a little with an abrasive disk and heavy grit sandpaper. Could have continued and had a smoother finish with a lot more sanding. Decided I had already diminished my return enough.

The important lesson I took away from this exercise is, if I need/want two 2" x 8" x 1/2" copper bars, buy them. Or at least, buy one 2" x 16" so you only have to make one 2" cut. I got a good price on the 4" x 8" x 1/2" piece from eBay, $40 with free shipping (that sucker is heavy), but the aggravation and time to "get 'er done" was too much.

Now I am ready to drill the holes and install the bolts, but I have run into another problem. I bought stainless steel 3/8" bolts, washers, and nuts. And then, I found the following chart on the Blue Sea Website. It shows the conductivity of various metals, compared to copper at 100%:

Conductivity of Metals

Material IACS % Conductivity
Silver 105
Copper 100
Gold 70
Aluminum 61
Nickel 22
Zinc 27
Brass 28
Iron 17
Tin 15
Phosphor Bronze 15
Lead 7
Nickel Aluminum Bronze 7
Steel 3 to 15

If I am reading this chart right, it sounds like my (stainless) steel bolts are the worst things to use to connect wires to the copper bus. I had planned to use the SS washers at the busbar, but it appears that I must have the tinned copper lugs touching as much of the copper plate as possible. I guess I could stack the lugs onto the bolt, next to the copper and use the SS bolts, washers, and nuts as a mechanical device to hold them in position. If I am stacking some terminals on a bolt, would I gain any benefit from placing a copper washer between them?

Or am I just overthinking my project?

I would appreciate any advice and suggestions, especially from those who have been there, done that!

Thanks,

Trent

Re: Battery Cable Upgrade and Pricing

Reply #26 – February 15, 2016, 07:29:35 am

Trent I am not totally sure on this but I think with copper Bronze bolts, nuts and lockwashers should be used. Is it possible to contact the local power company and ask. Also check with google.

Re: Battery Cable Upgrade and Pricing

Reply #27 – February 15, 2016, 09:28:27 am

So, silver conducts more lectricity out than is put in ?

Re: Battery Cable Upgrade and Pricing

Reply #28 – February 15, 2016, 09:39:39 am

Quote from: toyman – February 15, 2016, 09:28:27 am

So, silver conducts more electricity out than is put in ?

Dave,

No, silver is a better conductor than copper. Which is why busbars in a power plant are silver clad.

Remember, this conductivity chart compares the conductivity of various metals, based on the conductivity of copper, which is rated at 100%.

There were several real surprises to me, such as brass at only 28%. Lead is shown at only 7%; I had always thought the battery cables in a car were lead, which is why it is so easy to spread them to remove from the battery. Must have been an old wife's tale.

Hope this helps,

Trent

Re: Battery Cable Upgrade and Pricing

Reply #29 – February 15, 2016, 11:39:00 am

I have confirmed that 4' cables will reach from the chassis batteries to the under-bed location for my busbars.

The 4/0 battery terminal lugs came from Zorotools. The 4/0 tinned copper terminals with 3/8" hole came from China on a slow boat (via eBay). The inside diameter for all three is approximately 0.57". The outside diameter for the busbar end is about 0.74"; the wall thickness is 0.09". The OD for the battery end is about 0.84"; the wall thickness is 0.14".

The markings on the "3/8 inch" terminals are "120-10"; the 120 is the nominal size for 4/0 cable, and the 10 is for 10 mm, a tad larger than 3/8". The 120 appears to be the right size crimper die for those terminals, but I am concerned about the battery lugs. Their OD's are clearly 0.10" larger than the smaller lugs. The difference appears to be the wall thickness of the lugs.

I have never tried crimping terminals for a large size wire. It would seem that the larger lug might need the next larger crimper die. Or maybe I just start with the larger size and revert to the 120 size once the crimp has started? Or do I just use the 120 from the git-go, and use my 16 ton hydraulics to accomplish the crimp? I don't know.

Any experienced crimpers out there? Given where I am now, how should I proceed?

Thanks for any helpful feedback,

Trent

Re: Battery Cable Upgrade and Pricing

Reply #30 – February 15, 2016, 11:45:08 am

I've crimped thousands of lugs but the problem is that we use much more expensive equipment than what you are using and the lugs and dies are coordinated for each other (lugs color coded and/or stamped with a crimper die number).

You'll end up having to use trial and error if there isn't coordination between the lugs and dies, as far as I can tell.

Re: Battery Cable Upgrade and Pricing

Reply #31 – February 15, 2016, 12:18:40 pm

Robert,

Thanks for the feedback.

I can understand the OJT/Trial&Error/SchoolofHardKnocks method of learning. I was smart enough to have bought 20 of the 3/8"/10 mm terminals (about $32), so I have some extra there. I also got seven each of the positive and negative battery lugs (about $6 each), so I have extra there, also. The cost of the 4/0 is not inconsequential, but the cost of education is never totally free.

How would your equipment handle the 0.1" difference in OD for the standard lugs versus the heavy duty lugs, or would they just be two different dies?

Thanks,

Trent

Re: Battery Cable Upgrade and Pricing

Reply #32 – February 15, 2016, 01:11:06 pm

It would likely be two different dies. Everything we use for 4/0 and larger wires would probably fall under what you call heavy duty lugs. Things like this:

Blackburn Compression Connectors

http://www.ilsco.com/e2wShoppingCatalog.aspx?parentId=3100012197&parentLink=2100001183:3100012197

Re: Battery Cable Upgrade and Pricing

Reply #33 – February 15, 2016, 07:26:30 pm

Quote from: TulsaTrent – February 15, 2016, 12:18:40 pm

Robert,

Thanks for the feedback.

I can understand the OJT/Trial&Error/SchoolofHardKnocks method of learning. I was smart enough to have bought 20 of the 3/8"/10 mm terminals (about $32), so I have some extra there. I also got seven each of the positive and negative battery lugs (about $6 each), so I have extra there, also. The cost of the 4/0 is not inconsequential, but the cost of education is never totally free.

How would your equipment handle the 0.1" difference in OD for the standard lugs versus the heavy duty lugs, or would they just be two different dies?

Thanks,

Trent

Would this be any help to you? Quick Cable 4 0 Compression Ring Terminal Lug Cast Copper 5840F 3 8" Hole | eBay

Re: Battery Cable Upgrade and Pricing

Reply #34 – February 15, 2016, 07:57:29 pm

We use those ends at work, we have a hand crimper with rotating dies and 20 inch handles. There is also a crimper available that has a v bottom and an upper die you strike with a hammer that pushes centered in the v to squeeze the lugs. You may be able to find a hand crimper at a local truck repair shop.

Re: Battery Cable Upgrade and Pricing

Reply #35 – February 15, 2016, 08:34:11 pm

I bought the FTZ heavy duty crimper from Bay Marine Supply. I believe he still gives a 10% discount to Foreforum members. You might have to call to get the discount, but Alan (the proprietor) is helpful and great to work with. He also has the FTZ starter lugs, FTZ power lugs (thicker walled and very heavy duty), and FTZ batter terminal clamps for top post batteries. The tool works very well, though it does take some mechanical sense to get the best results. I found the best way to do it was to choose the appropriate gage by rotating the dies, place the lug in the die and squeeze just enough to grip it firmly. Then insert the already stripped cable in the lug and do a partial crimp (enough secure the lug so that it stays where you positioned it), then rotate the lug (or the tool) 90º squeeze the handles until the die bottoms out. Finally, rotate the lug or tool back to the starting point and do a full crimp there. If using the power lugs, I do cycle again, offset from the first run to widen the area of engagement.
Don
FTZ Heavy Duty Lug Crimp Tool

Re: Battery Cable Upgrade and Pricing

Reply #36 – February 15, 2016, 10:24:26 pm

Don, Another big supporter of Alan at Bay Marine here. He has been very helpful just helping to understand systems, diagnostic processes, what equipment does what and if and when you are ready to buy with that too. Discounts too for Forum members depending on product line, call and ask. And a fixed shipping fee of less than $9. It is rare to find a resource like Alan who will take the time to talk to you, help you learn and remember who you are the nxt time you call back! I usually send him an email with what I need help with and ask when a good time to call would be. He lets me know when he will have time to chat. Good for me and helpful for him.

I recently bought an FTZ crimper from Alan. I was pleased that he threw in a bag of several different sized lugs to cover the trial and error learning curve.

Re: Battery Cable Upgrade and Pricing

Reply #37 – March 05, 2016, 02:56:25 am

I have created my six new 4/0 battery cables. All are 4' long, with a battery terminal lug on one end and a 3/8" lug on the other. I made them without wasting any wire or terminals! I used the 120 mm2 dies for the standard 3/8" terminals, and 150 mm2 dies for the heavy duty battery terminal lugs. All went according to plan. I used triple wall adhesive-backed heat shrink for the black cables, and double wall adhesive-backed heat shrink for the red cables.

I have finished drilling the holes for the bolts in the bus bars and prepared the standoffs under the bur bar mounts. Originally, I was planning to use 1" x 3/4" composite blocks on top of the quilted thermal lining in the engine department. Finally decided to go with another composite standoff, which was about 2 3/4" high, giving me plenty of room to get the 5/16" Allen wrench under the bus bars to hold the socket head bolts in place while fastening the nylock nuts onto the cable lugs.

I had planned to tap the holes in the bus bar to better secure my 3/8" bolts. After a few attempts, I gave up. I would turn the tap a little and try to back it off, but it did not cooperate in the 1/2" copper.

Tomorrow I will take pictures and install them.

Trent

Re: Battery Cable Upgrade and Pricing

Reply #38 – March 05, 2016, 11:43:03 am

Trent, I had no problem tapping my Bus Bars for the bolts.I guess you did use a taper first and with lubricant??
JohnH

Re: Battery Cable Upgrade and Pricing

Reply #39 – March 05, 2016, 12:07:30 pm

Copper does come in different grades of machinability/etc. Possibly you had a tap drill that would yield over 75% of thread. Most tap drill charts specify a tap drill that would yield anywhere from 70% up to 85% of thread. The tap drill manufacturers do like to sell taps, and the tap will break sooner with a higher percentage of thread.
Find the size tap drill that will yield 55% of thread & tapping will be easier.
I no longer have my Bendix Besly tap book or I would have posted the correct size.

Re: Battery Cable Upgrade and Pricing

Reply #40 – March 07, 2016, 02:24:22 am

Final Update for First Phase of Battery Cable Upgrade:

I have now finished my bus bar, new cables, and new engine battery installation. I will explain where I ran into difficulties and how I resolved those problems, along with pictures.

I created six 4' 4/0 cables to go from my new batteries to my new bus bars. These all had battery terminal lugs on one end, and a terminal lug on the other end with a 3/8" hole on the other (actually 10 mm, but who is measuring?). You may recall that when I purchased my two 50' rolls of 4/0 welding wire, the red wire was priced at $198, and the black at $249; I bought two red rolls. In assembling the "black" cables, I started by pulling a 4' piece of heat shrink on the red cable and heated it prior to working with the terminals lugs. I used a mini pipe cutter to cut the insulation off of the cable ends prior to crimping on the terminals.

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I used triple wall heavy duty heat shrink for the black lugs, and double wall heavy duty shrink wrap for the red lugs.

I used 3/8" x 16 x 1 1/4" socket head stainless steel bolts and nuts for the bus bar studs. The bus bars were mounted to a double wall composite box frame left over from installing vinyl fencing on my upper deck. This was approximately 2 3/4" high, which mounted the bus bars far enough away from the mounting surface to allow removal of the bolts if I needed to install a longer one. Also, it left plenty of room for the 5/16" Allen wrench to hold the bolt heads for tightening the nylock safety nuts.

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The bus bars were 2" x 8" x 1/2" copper (cut from a 4" x 8" bar). My original design concept was to have three bolts/studs on the bottom row of each bar for the three leads from my three new batteries; the other wires/cables to the bus bars could use the two bolts/studs in the top row. And this is how they were initially installed. When I went to add another cable to the top row, I realized my 3/8" lugs were too big to fit on the same side, so I moved two of the battery cables to the underside of the bus bar, which resolved the problem. When I make the bus bars for the coach battery bus bars, I will start with a 6" x 6" x 1/2" bar, which the seller has already agreed to cut them in half for me.

The next problem I ran into was from removing the original wiring harness (which was 3/0 wiring; not 4/0) for the two-battery system on my 2000 U295. It looked like the harnesses went to one of two standoff brackets, one positive and one negative. The problem was that the harness did not have a separate cable going to the standoffs, but used a double terminal on the far end of the battery harness. To remove it from the RV, I used a cutter wheel to cut off the battery harness at the junction, which left the other end of the continuing cable attached to the brackets. I then created two 3' cables, each going from the bus bar to the bracket. This was not a problem for the positive bracket, but the ground bracket did not have room to add another lug. I used a through-threaded nut to hold the larger lugs on the ground bracket post and then a 3/8" bolt and nut to add the other wires/cables to the ground bracket post.

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The battery cable wires dropped down from the bus bars and were routed to the respective battery terminals. Instead of the angle iron that was placed on top of the two old batteries, I used a 1/2" square tube to hold down the three new batteries. I also wrapped it with 3M splicing tape to avoid any chance of it actually causing a short between battery terminals.

The next phase of this project will be replacing more of the smaller cables with new 4/0 welding cable. At some point, I will get the copper bars to change the coach battery system to bus bar architecture with 4/0 welding cables to replace the smaller cables used originally.

If you have any questions or seek clarification, just ask.

Hope this information helps,

Trent

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Re: Battery Cable Upgrade and Pricing

Reply #25 – February 14, 2016, 11:39:36 pm

Re: Battery Cable Upgrade and Pricing

Reply #26 – February 15, 2016, 07:29:35 am

Re: Battery Cable Upgrade and Pricing

Reply #27 – February 15, 2016, 09:28:27 am

Re: Battery Cable Upgrade and Pricing

Reply #28 – February 15, 2016, 09:39:39 am

Re: Battery Cable Upgrade and Pricing

Reply #29 – February 15, 2016, 11:39:00 am

Re: Battery Cable Upgrade and Pricing

Reply #30 – February 15, 2016, 11:45:08 am

Re: Battery Cable Upgrade and Pricing

Reply #31 – February 15, 2016, 12:18:40 pm

Re: Battery Cable Upgrade and Pricing

Reply #32 – February 15, 2016, 01:11:06 pm

Re: Battery Cable Upgrade and Pricing

Reply #33 – February 15, 2016, 07:26:30 pm

Re: Battery Cable Upgrade and Pricing

Reply #34 – February 15, 2016, 07:57:29 pm

Re: Battery Cable Upgrade and Pricing

Reply #35 – February 15, 2016, 08:34:11 pm

Re: Battery Cable Upgrade and Pricing

Reply #36 – February 15, 2016, 10:24:26 pm

Re: Battery Cable Upgrade and Pricing

Reply #37 – March 05, 2016, 02:56:25 am

Re: Battery Cable Upgrade and Pricing

Reply #38 – March 05, 2016, 11:43:03 am

Re: Battery Cable Upgrade and Pricing

Reply #39 – March 05, 2016, 12:07:30 pm

Re: Battery Cable Upgrade and Pricing

Reply #40 – March 07, 2016, 02:24:22 am

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