Batt To Inverter Cable Length Question

[btrayfors]

ExMaggieDrum,

Excellent post. You've covered many of the concerns that many/most marine electrician professionals have, especially those who work on cruising boats with those big sticky-uppy things :-)

Yes, in a perfect world you could get away with using welding cable. But, most of us don't live in that perfect world, and if you're around boats very much and working on their electrical systems you'll know that ExMaggieDrum speaks the TRUTH.

One further thing not mentioned: a good crimp on a first-class lug for 2/0 or 4/0 or most any size cable requires a really good crimper. And, alas, these are expensive, no matter how you cut it.

In my experience very few cruisers have top-notch crimping tools. Rather, they depend on cheapie solutions and, as a result, have crimps that may look good but are inferior in several respects.

What's a good crimper look like? Here's one:



What's a good crimp look like? Here's one, before applying the adhesive heat shrink:



What's the proof? Here's one where the crimp has been cut thru with a hack saw, displaying the solid cable mass inside:



Crimps should be air free and gas tight. Just to help the adhesive heat shrink along a little :-)

Bill

[exMaggieDrum]

Originally Posted by transmitterdan

If you don't want to believe me read the Practical Sailor test results. All wire corrodes in salt water/fog environments. It's a fallacy that bare tinned wire will survive a long time without being protected. Tin plating that is corroded doesn't look as bad (isn't green) as corroded copper thus the myth that it corrodes less. That and a lot of people make extra profit from the myth.

Locomotive cable is also a good choice.

I guess we will have to agree to disagree. My background is chemistry before boat wiring. I do understand a bit about chemical reaction differences between tin and copper. I can't speak to the Practical Sailor tests. I do believe my own experience though and bare copper will always corrode faster and to a greater degree than tinned copper. Silver coated wire is even better (as someone said above), and gold better than that but I am not recommending those. Actually solid silver or gold would be the best of all.

[hellosailor]

"The thin strand argument doesn't make sense unless"
I don't argue the point, I only repeat what I've heard on this. That IF you eventually have any moisture and oxidation, that physically eats into the metal on each strand, and with thinner strands, you've got more surface area (and less cross-section) in each strand, so a "small" amount of corrosion can literally cut a thin strand, when it would only degrade a thicker one.
In theory that makes the thinner strands of welding cable more vulnerable to damage from corrosion. (Please feel free to perform your own salt air tests.(G))


As to sealing a cable with proper adhesive sleeving? Nice theory. In practice, insulation sometimes has pinholes, or gets punctured by wire strands or chafe. IF that happens, a properly sleeved sealed cable is still going to be thermal cycled, and every time it cools down and "inhales" fresh moist air through that pinhole, it will suck in moisture that can eat the cable.


How likely is any of that?


I don't care, if an extra $50 will ensure that it simply CAN'T happen. I like eliminating failure modes. I sleep better. You pays your money, and takes your choices.

[exMaggieDrum]

Originally Posted by btrayfors

ExMaggieDrum,

Excellent post. You've covered many of the concerns that many/most marine electrician professionals have, especially those who work on cruising boats with those big sticky-uppy things :-)

Yes, in a perfect world you could get away with using welding cable. But, most of us don't live in that perfect world, and if you're around boats very much and working on their electrical systems you'll know that ExMaggieDrum speaks the TRUTH.

One further thing not mentioned: a good crimp on a first-class lug for 2/0 or 4/0 or most any size cable requires a really good crimper. And, alas, these are expensive, no matter how you cut it.

In my experience very few cruisers have top-notch crimping tools. Rather, they depend on cheapie solutions and, as a result, have crimps that may look good but are inferior in several respects.

What's a good crimper look like? Here's one:

Attachment 96032

What's a good crimp look like? Here's one, before applying the adhesive heat shrink:

Attachment 96032

What's the proof? Here's one where the crimp has be cut thru with a hack saw, displaying the solid cable mass inside:

Attachment 96030

Crimps should be air free and gas tight. Just to help the adhesive heat shrink along a little :-)

Bill

Good explanation.

I have the same crimper as you show in your pics but there are others just as good. A good crimper should provide even force around the circumference of the lug and not leave any sharp edges to nick the heat shrink. The heat shrink should be put on as far as possible on to the lug but not to where the lug flairs out and not too far to be pinched by the nut on the terminal. And the insulation should not be cut back too far so there is a large gap between the insulation and the lug. The heat shrink should also extend at least an inch or more past the each of the insulation. And it should be heavy wall heat shrink as I noted - for cables above 8-10 gauge.

[FlyingCloud1937]

The number one reason not to use welding cable as boat cable is because it does not have a UL 1426 rating. That's because it has never been tested as such.

The number two reason is that insurance surveys are now starting to call this out, when welding cable is used.

I have had three boats this last year, where the owner had 90 days, to replace all welding cable with proper boat cable, or else loose the Ins. Policy. Three different surveyors.

Lloyd

[exMaggieDrum]

Originally Posted by FlyingCloud1937

The number one reason not to use welding cable as boat cable is because it does not have a UL 1426 rating. That's because it has never been tested as such.

The number two reason is that insurance surveys are now starting to call this out, when welding cable is used.

I have had three boats this last year, where the owner had 90 days, to replace all welding cable with proper boat cable, or else loose the Ins. Policy. Three different surveyors.

Lloyd

I have not read the UL standard in some time but I think it also calls for flame resistance that is above what welding cable needs. This is important on boats. I can't find a complete listing for the standard that I don't have to pay for.

The issue with insurance companies does not surprise me. They end up being the ones who have to pay for poor materials/installation for those who have insurance. And they see far more instances of cable failure than I do (which has been significant) and have been drivers for needed improvements in safety and property loss in a variety of areas on boats (like propane tank installations).

[btrayfors]

Originally Posted by FlyingCloud1937

The number one reason not to use welding cable as boat cable is because it does not have a UL 1426 rating. That's because it has never been tested as such.

The number two reason is that insurance surveys are now starting to call this out, when welding cable is used.

I have had three boats this last year, where the owner had 90 days, to replace all welding cable with proper boat cable, or else loose the Ins. Policy. Three different surveyors.

Lloyd

Absolutely right! Same thing happening around the Chesapeake.

And, while we're at it, the OP spoke of inverters installed above his batteries. This is a no-no, and the ABYC specifically prohibits it:

A25 Power Inverters:

"25.6.3 Inverters shall not be installed directly over batteries."

Savvy surveyors will ding you every time.

Bill

[FlyingCloud1937]

Link to the UL 1426 Test Requirements

Originally Posted by exMaggieDrum

I have not read the UL standard in some time but I think it also calls for flame resistance that is above what welding cable needs. This is important on boats. I can't find a complete listing for the standard that I don't have to pay for.

The issue with insurance companies does not surprise me. They end up being the ones who have to pay for poor materials/installation for those who have insurance. And they see far more instances of cable failure than I do (which has been significant) and have been drivers for needed improvements in safety and property loss in a variety of areas on boats (like propane tank installations).

[FlyingCloud1937]

Construction
2. Conductors ................................................ 5
3. Insulation ............................................. '.' .. 5
4. Grounding Conductor ...................................... 6
5. Color Coding .............................................. 6
6. Conductor Assembly ........................................ 6
7. Nonmetallic Jacket (Optional) ................................ 6
8. Physical Properties of Insulation and Jacket .................... 7
9. Conductor Corrosion ....................................... 7
10. Heat-Shock Test ........................................... 7
11. Flexibility Test ............................................. 8
12. Deformation Test .......................................... 8
13. Cold-Bend Test ............................................ 9
14 . Vertical Flame Test (Insulated Conductors) .................... 9
15. Vertical Flame Test (Completed Cable) ....................... 10
16. Mechanical Water Absorption Test .......................... 10
17. Specific Inductive Capacity Test ............................. 10
18. Dielectric Voltage-Withstand Test and Alternatives ............. 10
19. Insulation Resistance Test at 60°F (15.6°C) ................... 11
20. Insulation Resistance Test at Elevated Temperature ............ 14
Markings
21. Tag Marking ............................................. 16
22. Cable Marking ........................................... 16

Originally Posted by exMaggieDrum

I have not read the UL standard in some time but I think it also calls for flame resistance that is above what welding cable needs. This is important on boats. I can't find a complete listing for the standard that I don't have to pay for.

The issue with insurance companies does not surprise me. They end up being the ones who have to pay for poor materials/installation for those who have insurance. And they see far more instances of cable failure than I do (which has been significant) and have been drivers for needed improvements in safety and property loss in a variety of areas on boats (like propane tank installations).

[Cadence]

Originally Posted by rwidman

See post #21

Ron,

Sorry I missed it. He pointed out why.

Roger

[transmitterdan]

I agree cable should meet applicable flame and temperature ratings. I also agree that a proper crimp is necessary. GenuineDealz will put on the lugs using the right crimper before shipment.

But does ABYC mandate tinned wire? Last I knew they did not.

I also have experienced surveyors complaining about things. Sometimes they are wrong so it pays to look up the rules yourself. Is there a place online where one can legally read all the ABYC rules?

[DeepFrz]

But does ABYC mandate tinned wire? Last I knew they did not.

I don't think so but when I went back to look at the welding cable that I linked to above I notice that it does not have the specs. printed on the insulation as UL rated wire does. This could, as has been pointed out, have serious consequences when it comes time to insure the boat or to sell it.

[rwidman]

Originally Posted by colemj

Perhaps instead of just setting yourself up as an expert that is never to be questioned, maybe you could expound on why appropriately spec'd welding cable is inappropriate for this application?

Mark

Because I don't want to waste my time arguing with someone who just wants to argue.

[FlyingCloud1937]

I don't know of anyone selling UL rated boat cable that is not tinned, so that issue is moot.

All UL rated boat cable is required to carry the mark, and then some on the cable.

Lloyd

Originally Posted by transmitterdan

I agree cable should meet applicable flame and temperature ratings. I also agree that a proper crimp is necessary. GenuineDealz will put on the lugs using the right crimper before shipment.

But does ABYC mandate tinned wire? Last I knew they did not.

I also have experienced surveyors complaining about things. Sometimes they are wrong so it pays to look up the rules yourself. Is there a place online where one can legally read all the ABYC rules?

[transmitterdan]

I haven't searched the world for cable rated to this standard but the standard itself doesn't require tin plating.