DNV GL rules regarding wire nuts

Can anyone point me in the direction of DNV rules regarding the use of wire nuts? I have piles of crimp connectors (the same style as your typical wire nut), but was told twist on wire connectors were not allowed.

Google revealed this, but it isn’t really helpful.

801 Splicing
a) Splicing of cables by using a kit or system from a recognised manufacturer is accepted.
b) The two cables spliced shall have the same basic construction.
Guidance note:
Splicing is meant as the direct continuation of cable lengths and
not transfer into a distribution box.
The splicing kit should contain the following as minimum:

  • connectors for conductors, of correct size
  • splicing instructions.
    —e-n-d—of—G-u-i-d-a-n-c-e—n-o-t-e—
    802 Splicing in junction boxes
    a) Junction boxes may be used for splicing of cables when
    the following is complied with:
    c) All conductors shall be connected in permanently fixed
    terminals.

Here’s DNV guidelines for ships, edition JAN2018, a little more detailed:

Splicing of cables by using a kit or system from a recognised manufacturer is accepted. The two cables spliced shall have the same basic construction.
Guidance note:
Splicing is meant as the direct continuation of cable lengths and not transfer into a distribution box. The splicing kit should contain the following as minimum:
— connectors for conductors, of correct size
— replacement insulation
— replacement inner sheet or common covering
— connector for braiding or armour
— replacement outer sheath with minimum fire properties as the original sheath
— splicing instructions.

I also took it as gospel that wire nuts are a no go on a vessel but it seems they are not explicitly banned. However the criteria for acceptable splicing would rule the use of them out as sheathing and insulation shrink tubing cannot be reasonable put over nuts. Maybe they’re leaving room for the use of mastic tape, but who would put those over wire nuts? Vinyle tape over mastic with bug nuts is my preferred at sea splice in large cable if I can’t replace the whole conductor. The crimp style nuts you describe are also really cheap and I’ve replaced many that have had torn insulation from crimping at installation.

I’ve seen “Marine grade” wire nuts loaded with conductive grease and some type of protection in the open end but still pretty cheesy. They also don’t have the same bite on stranded conductors. I say leave them in the garage.

Full 2018 DNV regs for electrical installations:

Part 4 Systems and components Chapter 8 Electrical installations

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+1

I exclusively use either a crimping system with sufficient force to cause plastic flow of the conductor, or solder if I must. Over this goes a suitable waterproof insulator, mostly hot glue lined shrink hose, preferably integrated in the crimp or cold solder bushing. The rules may be a bit hazy, but there’s nothing like peace of mind, and few things worse than doubting your own terminations or splice work when hunting down a voltage drop.

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It’s not about splicing rules. See from your hyperlink to the DNV GL rules:

4.3.1 Termination
a) All equipment shall be provided with suitable, fixed terminals in an accessible position with sufficient space for dismantling and connection of external incoming cables. Twist-on or clamp-on connections inside connection boxes for lighting and small power consumers are accepted inside dry accommodation.

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Thank you for the responses.

This was the exact application I was looking for concerning wire nuts. Replacing lights/fan fixtures inside the accommodation.

That clarifies it. However I can’t recall working on an flouescent fixture that didn’t have a terminal block or screw/push in terminals so I dont see the need for nuts. Some domestic blowers for HVAC I have seen with the crimp style nuts but those were always economy units and not even close to Marine standard.

In a Marine/industrial setting what sort of small alternating current consumer comes with unaffixed leads that make wire nuts the best option?
Side note - I used to use them for bench testing but moved to cheap terminal blocks both so no one gets any ideas, and the differences in gauge and construction between light gauge solid core commonly found in flouro fixtures and standard 14AWG stranded cable make a mess when twisting together.

I’ll continue instructing the sparkies to make every connection screwed or crimped and sealed for piece of mind.

These little units are great for low power and signal connections. They use (more or less) the same holding technique as the push in DIN rail terminals. They make lighting fixture specific connectors as well.

https://www.wago.com/us/c/wire-splicing-connectors

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110v ventilation fan/light combos in the accommodation.