Wiring

[oldboot]

Yeh we arent talking about the self soldering heat shrink sleves.... I played with them when they first came out and wasn't impressed.
the soldering temperature was too low for my liking and unless your wires are completely clean & shiny the soldering can fail to take.

We are refering to what is like a normal crimp connector but the insulation is heat shrinkable with a glue lining.


One point with crimp lugs.
always tension test them after crimping......if you can pull the lug off the wire it's a fail.

one work process I trained on we hal a little spring ballance that you had to test the crimp lug to a specified tension to pass.

a good crimp tool is worth the money if you are going to do this stuff a bit.
I remember when I baught my favorite crimper it cost me $100 wholesale.
you can ge a prety decent ratchet crimper for half that these days.

cheers

[finga]

a good crimp tool is worth the money if you are going to do this stuff a bit.
I remember when I baught my favorite crimper it cost me $100 wholesale.
you can ge a prety decent ratchet crimper for half that these days.

cheers

That's why most blokes will solder and shrink.
You may have a crimper or two old mate and I have lots of crimpers but the average Jo Blo will not spend that much Johnny Cash on something they'll use 3 times in 5 years.
Hell... that's nearly 2 slabs

[Grand_Marlin]

With all this teknekal descushen goin on, it is easy to see why many people just twist the wires togetha and put electrical tape over them.

1) easy - anyone can do it
2) no special / expensive tools needed
3) easy access for replacing item down the track
4) Tinned wire? that must be old school - all wire comes on a plastic roll these days... any size or colour seems to work.
5) most modern switches have a hole already drilled in the terminal to allow you to put the wire through then twist it - if not, wrapping around several times and using silicone or electrical tape in a figure 8 will keep it there.
6) If you dont have a switch, just dab the hot wire on the battery as needed.
7) fuses? .... more like confuses - dont know what size or where to put them, so leave them out ... just another thing to go wrong.
8) getting power by cutting into your engine harness is always reliable - they always seem to have good power supply



Sadly, the rubbish I just wrote above, I have seen & heard in many cases over the years.

Marine electronics is a major part of my business, and I believe:
1) always use tinned copper wire - it is available in all sizes up to 6mm, which is the biggest you will need for any accessories on a boat (except electric winches etc)
2) Always use the right size wire for the job - check the amp draw of the accessory first.
3) always use a fuse size that a) is recommended by the manufacturer of the product and b) is never greater than the amp rating of the wire. Generally 6mm wire is rated to 30 amp, 4mm wire is 15 amp and 2mm - 3mm wire is 10 amp
4) always use waterproof fuse holders.
5) always make waterproof joins, as the other boys have stated.
Personally, I use the Quickcrimp brand joiners with the heatshrink casing and glue resin. I find these are excellent. I use them up to 6mm.
Over this size is a different story.
6) Be very careful soldering to the back of a switch panel, as you can easily melt the plastic switch casing.
7) I always run a dedicated power cable to a bus bar setup behind the dash - one positive, one negative. Then I run all accessories off of the bus bars with their own fuses.

In the pic you can see the pos and neg bus bars, the waterproof fuse holders (most of them) and the yellow heat shrink joiners.

Cheers

Pete

[oldboot]

I have to conceed that it is probaly just as easy to do a bad crimping job as it is to do a bad soldering job.
I have seen some pretty damn awfull crimping work.

Those of us who have "all the gear" and have the experience..... the mothod matters little because we will have what it takes, on hand to make that method work.

But I would say it is easier and more convienient to do a good crimping job than to do a good soldering job... for the average mug.



for may years up untill I spent up big (& at the time that was a lot of money to me) on a realy nice crimper I had used a variety of cheaper crimpers........ some good some bad.

As long as the crimper isnt absolute junk, with a little care you shloud be able to produce a good crimping job.

Its just a matter of paying attention and ensuring the lug is well crimped.
On cheaper crimpers we used to crimp with the correct colour section then firm it down with the next smallest section.

Most of the problems I have seen result from either the incorrect lug for the wire being used or an incorrect crimper...... usulay a pair of pliers being used.

so how to crimp properly

lets start by saying we are talking about insulated lugs here
these are the ones that come in red, blue and yellow
there are a variety of other lug types arround but we problay don't want to use those.

so we need a crimper for insulated lugs

If you want a cheap crimper thats fine..... look at it and make sure the jaws mate up properly and wehn you grab it by the handles and squeese with the full force of your hand it doesnt buckle & flex ( too much)
I've never had any time for pliers or wire strippers that have crimpers as an after thaught added....... they usualy either arent correct or don't have the leverage.

now we need lugs
the three colours denote compatble wire size... red is the smallest, blue is bigger and yellow is the largest.
I wont go into what fits what.....the tolerance varies from manufacturer to manufacturer and depending on what market they are intended for.
the important thing is the hole where the wire goes in the lug should be at least 75% full of wire for a correct crimp, some lugs are less tolerant than this.
so when you present the wire up the hole in the lug should be pretty full of copper.

we need to strip the wire to the correct length
the best way is to get a ring lug and look at that because you can see both ends of the crimping tube
With the insulation butted up against the inside of the lug the copper should extend just a little past the end of the crimping tube.
too short isn't good and this can cause the wire to be pushed out of the lug while crimping....... too long is just untidy and may stop the lug from mating up with another in the case of spades or bullets.

now to crimp
look at your lug. ( better still cut one apart to see) there is a section with a the crimping tube in it... that is usulay thinner... behind that there is a ( usulay fatter section) that is the strain relief for the insulation.

we want to crimp right in the middle of the section with the crimping tube in it.

present your wire up so the copper is inside the crimping tube with all the strands captured in the tube...... and the insulation butting up against the back of the crimping tube.
I will usulay hold the wire between my thumb and second finger with my forefinger pressing on the end of the lug to hold it in place.
place the correct jaws of the crimper.....there should be matching colour dots on the crimper. over the correct part of the crimper.

and Squeeeeeese.... firmly stediliy and as hard as you can ( unless you are a gorilla)....you should feel the lug compress and then become firm.......if it isnt a ratchet crimper..... don't let go and give it another squeese......it should feel hard.

now put down the crimper and grab the wire and the lug and pull..... you shouldn't be able to pull it of because the wire should now be almost cold welded in the lug.

all good

now crimp down the stran relief immediately where the wire enters the lug..... (well a small amount back from the edge).... but dont squeese too hard or you may squash the insulation too much.

some say to crimp the strain relief with the next bigger section of the crimper.

good all done.

Those of us with a background in this will have had this beaten into our skulls from a young age........ but I have never seen it written down for the average bloke.

I hope this helps.
the other blokes may have points to add.

cheers

[oldboot]

Oh one point.

when crimping, the lug should be flat in the crimper jaws.
Like the flat portionn of the lug (or if it was flat) would be on a line paralell with the line of the closed jaws.
Because
most lugs have a join in the crimping tube.... we want to press on top of this join to close it rather than pressing on the sides of the tube which would open this seam.

so the seam should be in the middle of the top or bottom jaw.

cheers

[FrankFWM]

For the record, the ABYC standards for wiring in relation to joints are as follows:

ABYC Section E-8.15.19
Solder shall not be the sole means of mechanical connection in any circuit. If soldered, the connection shall be so located or supported as to minimize flexing of the conductor where the solder changes the flexible conductor into a solid conductor.

ABYC Section E-8.15.20
Solderless crimp on connectors shall be attached with the type of crimping tools designed for the connector used, and that will produce a connection meeting the requirements of ABYC E-8.15.15.

The possibility of strain hardening caused by low frequency vibration present on vessels mandates the exclusive use of stranded copper wire (ABYC E-11.16.1.2.5. and ABYC E-11.16.1.3.7.). Tinned, stranded copper wire is the preferred wire conductor for use in marine electrical systems because it offers maximum protection against corrosion. At junctions, this wire is galvanically compatible with tin plated terminals. This compatibility helps prevent high resistance connections, overheated junctions, and fires.

Soldering is not recommended for terminal connections because it forms a hard transition which is prone to fatigue failure

Tape (alone) is not an adequate insulator nor sealant.

Hope this helps...

Frank