Battery Cable Washers - Oh My

[CCNorth]

I have new Trojan 875's for my 2009 CC Precedent IQ. I have ordered a new motor, Alltrax 500a controller, HD solenoid and cables from Revolutions, David Hicks, and will install soon.

For days, I have been searching for information about the proper washers to use on top of the battery cable. I'm surprised how little information I could find and what I did find is not consistent. I know how important it is to have the proper connection.

I found this information but I can't remember where. Sorry.

"Lock washers are ok as long as you use a regular washer between it and the ring terminal. All of our 48 V dc power plants use stainless washers and stainless lock washers with mechanically crimped ring terminals. The problems start when you use several ring terminals of different sizes and don't stack them correctly."

1. Do I use only a lock washer?
2. Do I use a stainless steel washer and a lock washer?
3. Is a washer necessary? Trojan battery website does not mention using a washer.

4. How do you "correctly" stack terminals of different sizes?

I have a new inch-lb torque wrench ordered so I can be sure I have them torqued correctly. I don't have enough experience to know if it's right just by feel.

Thank you for any help you might offer!

[Fairtax4me]

Your Trojans should have come with oversized stainless nuts. The oversized nuts are 5/16-18 thread with a 9/16 flat width. Regular sized 5/16 nuts are 1/2" flat width. If you didn't get stainless nuts with the batteries ask your supplier for them, or find a different supplier that has them.
Alot of people like to use lock washers. I don't use any washers because it's just another step, and something else to possibly corrode. With the oversized nuts you can torque them straight to the cable terminal and never have an issue with them coming loose.

Terminal stacking goes Largest First, then smaller wires after. Your main cables should be in direct contact with the battery post. Any smaller wires, such as charge leads, or wires for accessories or voltage converter should go on after the main cable and in order of size, largest to smallest.
Ideally you should limit making other connections to the batteries, If you have multiple wires that need to be connected move those other wires to a fuse block and use one larger wire to supply the block. If you need to connect other wires be sure to use heavy duty 5/16" eyelet crimp connectors. I like the yellow ones because they have the thickest material and provide more surface contact to the cable terminal.

[R&TBabich]

Originally Posted by CCNorth

.... For days, I have been searching for information about the proper washers to use on top of the battery cable. ....

"Lock washers are ok as long as you use a regular washer between it and the ring terminal. ....

Our Interstate batteries came with SS extra wide hex head nuts which are probably 304 SS. 304 SS has good corrosion resistance. I consider battery terminals a corrosive environment so I like to use 316 SS which has excellent corrosion resistance. For years I've used 316 SS hardware on our boat and have had no corrosion issues. I try to limit all battery connections to one cable. Here's a pic of B+ connections that are moved to a fuse block. I'm preparing to install an Alltrax controller and they want to see a 400A fuse installed in the battery line so I added the fuse mounting block. It actually would be a good idea for even a stock controller to add a 250A fuse. I use a 316 SS 5/8" OD washer, split lock washer and extra wide hex nut on the battery connections. Most hardware stores only carry type 304 SS. Marine stores usually carry 316 SS because of its resistance to salt water corrosion. I usually get hardware from McMaster Carr.

[CCNorth]

Originally Posted by Fairtax4me

Your Trojans should have come with oversized stainless nuts. The oversized nuts are 5/16-18 thread with a 9/16 flat width. Regular sized 5/16 nuts are 1/2" flat width. If you didn't get stainless nuts with the batteries ask your supplier for them, or find a different supplier that has them.
Alot of people like to use lock washers. I don't use any washers because it's just another step, and something else to possibly corrode. With the oversized nuts you can torque them straight to the cable terminal and never have an issue with them coming loose.

Terminal stacking goes Largest First, then smaller wires after. Your main cables should be in direct contact with the battery post. Any smaller wires, such as charge leads, or wires for accessories or voltage converter should go on after the main cable and in order of size, largest to smallest.
Ideally you should limit making other connections to the batteries, If you have multiple wires that need to be connected move those other wires to a fuse block and use one larger wire to supply the block. If you need to connect other wires be sure to use heavy duty 5/16" eyelet crimp connectors. I like the yellow ones because they have the thickest material and provide more surface contact to the cable terminal.

I just double-checked and batteries did come with the oversized stainless nuts. I did measure them just to be sure. When I bought the batteries I asked salesman about washers and he said I did not need them. I wasn't sure he was correct. LOL
Now I understand the term "stacking". I thought that was what it meant. I know you said I should not have more than one connection to the battery terminal, but you know that I do. I realize it's not ideal. So, is a washer needed between the connections??

I've been sitting here studying the wiring diagram but have not gotten to the point of comparing it to my wiring. I have an extra Red wire (with heavy duty yellow ring terminal) connected to #1 battery Positive.
I have 2 extra connectors, a Red and a Blue, to the #4 battery Negative. The Blue wire runs through a red plastic fuse box.
I plan to correct this wiring after I study it and be sure I understand.

Thank you so much!!

[CCNorth]

Originally Posted by R&TBabich

Our Interstate batteries came with SS extra wide hex head nuts which are probably 304 SS. 304 SS has good corrosion resistance. I consider battery terminals a corrosive environment so I like to use 316 SS which has excellent corrosion resistance. For years I've used 316 SS hardware on our boat and have had no corrosion issues. I try to limit all battery connections to one cable. Here's a pic of B+ connections that are moved to a fuse block. I'm preparing to install an Alltrax controller and they want to see a 400A fuse installed in the battery line so I added the fuse mounting block. It actually would be a good idea for even a stock controller to add a 250A fuse. I use a 316 SS 5/8" OD washer, split lock washer and extra wide hex nut on the battery connections. Most hardware stores only carry type 304 SS. Marine stores usually carry 316 SS because of its resistance to salt water corrosion. I usually get hardware from McMaster Carr.

As I told Fairtax, I do have extra wide nuts but no markings to indicate "what" they are. I do see three plus marks (+++) on the underside of the nut. The weight feels like stainless.

Your photo is great!! A real help to see how it's mounted and wired. From your picture and what FairTax said both the Red and Blue that I have connected to the #4 battery Negative must both be to the B+ voltage limiter? That red wire is confusing me.

Appreciate your help so much!! Could spend hours on McMaster Carr website. I'll check out the 316 SS nuts.

[R&TBabich]

Originally Posted by CCNorth

.... I do have extra wide nuts but no markings to indicate "what" they are. I do see three plus marks (+++) on the underside of the nut. The weight feels like stainless. ....

I have a lot of 18-8 SS hardware and according to McMaster Carr "18-8 refers to stainless steel that has approximately 18% chromium and 8% nickel; it generally applies to 301, 303, and 304 stainless steel". In the pic the 1st nut has 3 plus marks (+++) and are 18-8s from McMaster. The nuts that were on my Interstate batteries are the 2nd one in the pic and has "304" stamped on it. The nuts I ordered from McMaster have "316" stamped on them. A plain steel nut will stick to a magnet, these do not. I only use a washer between the wire connection stack and the split ring lock washer.

[rib33024]

You don't need any washers, anywhere on the batteries or cables

[Fairtax4me]

Red wire connected to battery 1 should be 10awg and it goes to the charge receptacle +.

Red and Blue wires on battery 4 should probably not be there, for a couple reasons. One is that whichever accessories those are powering, they're only getting 12v from that battery. Eventually that causes that battery to become out of balance with the rest (depending how often and for how long you use the accessory), which leads to uneven charging and different state or charge between batteries in the pack. This leads to some batteries being chronically Undercharged, which causes sulfate buildup on the plates, and degradation and loss of capacity.
12v accessories should ideally be powered by a voltage reducer that draws its energy from the whole pack, rather than just one battery.
The other reason is, the energy being used by those accessories is not being accounted for by the OBC, and is not being correctly replenished during charging. (assuming your cart still has the OBC and uses the Powerdrive charger) This will eventually cause the entire pack to be undercharged, and the one battery will be severely undercharged.

You said your "blue" wire goes to a fuse holder, which probably means it goes to a light kit. Does the other red wire on battery 4 go to a fuse? I know it's hard to see in the battery box where all the wires go. What kind of accessories are on the cart, and if you unhook that red wire, which one doesn't work?

[R&TBabich]

Originally Posted by rib33024

You don't need any washers, anywhere on the batteries or cables

I agree, washers are not needed.
I prefer to use lock washers to help keep a nut from working loose from vibration, particularly on connections that can cause a problem if it becomes loose.
I use a washer under a lock washer to provide more even pressure to what is being held down and have something for the lock washer to get a bite on.

[scottyb]

Everybody is different & to each their own.
I notice when washers are used it creates additional places for corrosion to build above and below the washer.
I use a truss head serrated stainless nut . It covers all the bases in one piece.
McMaster and Carr fans know where to go

Super-Corrosion-Resistant 316 Stainless Steel Serrated Flange Locknuts

These flange locknuts have excellent resistance to chemicals and salt water. Serrations grip the material surface instead of the threads for easy installation and mild vibration resistance. The flange distributes pressure where the nut meets the material surface, eliminating the need for a separate washer. Height includes the flange. Nuts may be mildly magnetic.


316 Stainless Steel Serrated Flange Locknut, Super-Corrosion-Resistant, 5/16"-18 Thread Size
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