Conduit

[ChrisL]

I’m about to do my first fix electrics

my 12v lights will be in a central roof duct 

But my question is reference to running 12v and 240v at the gunnels, I know I have to separate these. So my thought is run the 12v in either a flexi conduit or a plastic duct

What I’m trying to understand which is best way to bring out the cables from the said ducts/conduit ie Tees etc 

Any recommendations would be appreciated, hope I’ve explained my question ok

 

Edited September 10, 2023 by ChrisL

[Batavia]

I normally use rigid uPVC conduit.

For 12 volt circuits I have just drilled holes into the conduit, fitted them with grommets and brought the wires out directly to  fittings that are close.

For 230 volt circuits, I use normally use singles and proper conduit fittings throughout.

[BEngo]

I used the rectangular PVC duct with a clip on lid.  You will need to estimate the cable bundle size in order to choose the right version.  Mine is mostly 25x25 with some 25x50.  Elbows and Tee fittings  are available to keep things neat.  Leave some room for future growth!

 

For a single cable exit you can just cut away the side wall of the ducting  for a a few mm or drill a hole in the side wall. and grommet it. The lid will support the sides on either side of the hole.

 

For a big cable bundle exit  use a Tee.

 

For 240 V, because Arctic cable has the conductors oversheathed in blue it is accepted practice that the blue sheath provides adequate protection and separation.  The 240V cable can then run in the same duct as the 12 V cables.

 

When installing take care to keep your cable bundles combed, with all the cables parallel.  It is much more space efficient than a random bundle and makes cable tracing later on much easier.

 

N

[MtB]

3 hours ago, BEngo said:

When installing take care to keep your cable bundles combed, with all the cables parallel.  It is much more space efficient than a random bundle and makes cable tracing later on much easier.

 

At Decca we used what we called "idents" to identify cables. Little sleeves with digits on them that slid over the insulation, put the same number on each end so every cable termination had a number on it you could look up in the chart or circuit diagram and find the other end easily, wherever it was in the radar display. Some of the looms would have many dozens of conductors.

[Tracy D'arth]

This stuff is convenient.

 

https://duckduckgo.com/?q=plastic+cable+tray&atb=v314-1&iax=images&ia=images&iai=https%3A%2F%2Fimage.made-in-china.com%2F2f0j00ndhtBmecNskJ%2FQuick-Deliver-Date-25X25mm-PVC-Cable-Trunking-for-Electrical.jpg

[cuthound]

3 hours ago, MtB said:

 

At Decca we used what we called "idents" to identify cables. Little sleeves with digits on them that slid over the insulation, put the same number on each end so every cable termination had a number on it you could look up in the chart or circuit diagram and find the other end easily, wherever it was in the radar display. Some of the looms would have many dozens of conductors.

 

The builder of my boat had the foresight to do this. Makes faultfinding a doddle, at least on the original wiring.

[koukouvagia]

Don't forget to add a draw wire/string to make it easier to add extra cables later.

 

 

[BEngo]

1 hour ago, koukouvagia said:

Don't forget to add a draw wire/string to make it easier to add extra cables later.

 

 

If you use clip on conduit there is usually no need for draw strings.  Any extra cables can just be ferkled into the box and the lid replaced.

 

N

[Tynas]

It's important to ensure proper separation and organization of your 12-volt (12V) and 240-volt (240V) electrical systems on your boat to maintain safety and functionality. Running the cables in conduit or ducts is a good approach.

[Tracy D'arth]

21 minutes ago, Tynas said:

It's important to ensure proper separation and organization of your 12-volt (12V) and 240-volt (240V) electrical systems on your boat to maintain safety and functionality. Running the cables in conduit or ducts is a good approach.

Providing the 240v AC wiring is sheathed cable it can run in the same space as 12v/24v wiring but never the gas pipes.

[Alan de Enfield]

23 minutes ago, Tynas said:

It's important to ensure proper separation and organization of your 12-volt (12V) and 240-volt (240V) electrical systems on your boat to maintain safety and functionality. Running the cables in conduit or ducts is a good approach.

 

What are the regulations for attaching cables to gas pipes on boats ?

[IanD]

1 hour ago, Tracy D'arth said:

Providing the 240v AC wiring is sheathed cable it can run in the same space as 12v/24v wiring but never the gas pipes.

IIRC legally (BSS) it can do, but most people would say it's not a good idea and separate conduit for LV DC and HV AC is preferable. It's what most (all?) reputable boatbuilders do...

Edited September 11, 2023 by IanD

[koukouvagia]

2 hours ago, BEngo said:

If you use clip on conduit there is usually no need for draw strings.  Any extra cables can just be ferkled into the box and the lid replaced.

 

N

Though this wouldn't work if the conduit is hidden behind panelling.