Methods of connecting two led cabin lights to one switch

[lustyd]

does anyone smear vaseline over their terminals

In my experience all this really achieves is a mess unless it's an outside socket. If your boat is so wet that this is needed then spend your time making it dry.

 

[Alex_Blackwood]

Explain why, with references. Seriously.

Bear in mind that I am basically a "Heavy Electrics" man (Paul can deal with 12volt Stuff!) It is simply bad practice as the crimp can fail as I have personally observed on more than one occasion, and I am not alone! Paul gave examples of using larger crimps with smaller wires. Personally I would reserve judgement on that. I am just saying that in my experience two wires in a crimp don't always get securely gripped. I wouldn't do it and that is speaking from 65 years experience.

 

[Wing Mark]

Bear in mind that I am basically a "Heavy Electrics" man (Paul can deal with 12volt Stuff!) It is simply bad practice as the crimp can fail as I have personally observed on more than one occasion, and I am not alone! Paul gave examples of using larger crimps with smaller wires. Personally I would reserve judgement on that. I am just saying that in my experience two wires in a crimp don't always get securely gripped. I wouldn't do it and that is speaking from 65 years experience.

Any process can be buggered up by technicians, factory floor operatives, or worse still, amateurs.

There is no 'amateur proof' method.
The method and materials used are far less important than whether it's done with adequate skill and whether it's subjected to unreasonable abuse afterwards.

I think what a lot of boat owners need is guidance about checking a joint has been done right, whether it's solder, crimp, chocbloc, binding post or whatever. And more emphasis on not stressing joints.

 

[Moodysailor]

You have most of the answers in the above, I can provide some additional information on a couple of points. I don't do as much work in this area as @PaulRainbow but I am/was a qualified marine engineer and electrician (no longer work in that direct area, but still in the marine industry).

• Soldering is not advised as a sole means of connection, and if wiring to ABYC standards (a very good marine electrical standard), it is prohibited. Crimp & solder is accepted, solder only is not. The reasons are that solder is not mechanically as strong as a crimped connection, in the case of an overheat it can melt and come loose, and there is an increased risk of fatigue failure of multistrand wire where the solder finishes.
• Grease (including vaseline) is not advised on any electrical connections as it is an electrical inhibitor. When it warms it becomes more viscous, can flow into the terminal and lead to increased resistance. This is particularly an issue on higher current connections (i.e batteries). If a waterproof connection is required, use any one of the suitable methods designed for the job. If corrosion protection is required, also use the right method (and materials) for the job
• Heat shrink is not suitable for strain relief. It's purpose is electrical isolation and assisting with corrosion protection. If strain relief is required, this should be mechanical on the cable, not at the terminal
• Scotch-locks are the work of the devil. Anyone who has them should throw them all away immediately and advise anyone else to do the same.
• Wago connections are hard to beat for cost-effective, efficient, long-lasting, low current connections in dry areas.

A final comment is that a good engineer will have good quality tools, and use good good quality materials, they will also know which is the best one to use in which situation. Most of the guidance that has been issued over the years is intended to catch the vast majority of cases, so assumes below expert level of knowledge and application. Additionally, new tools, materials and methods come out that make life easier or reduce time. For this reason the industry tends to converge on common view points - it is a lot harder to mess up a crimp connection or a Wago and they are quicker than soldering. So this should not be taken so literally to say that solder connections are 'bad', just that there are other alternatives which achieve the same result but are faster and easier for a wider group of people to do well.

I stand by my comment regarding scotch-lock terminals...

 

[thinwater]

Bear in mind that I am basically a "Heavy Electrics" man (Paul can deal with 12volt Stuff!) It is simply bad practice as the crimp can fail as I have personally observed on more than one occasion, and I am not alone! Paul gave examples of using larger crimps with smaller wires. Personally I would reserve judgement on that. I am just saying that in my experience two wires in a crimp don't always get securely gripped. I wouldn't do it and that is speaking from 65 years experience.

Thanks.

No, I wouldn't chose to do that in industry with real power flows, but I have done this in control panels thousands of times without fault, and I've been servicing these panels all along. I supose it is about how it is done. Rachet crimpers and a proper fit up.

 

[thinwater]

You have most of the answers in the above, I can provide some additional information on a couple of points. I don't do as much work in this area as @PaulRainbow but I am/was a qualified marine engineer and electrician (no longer work in that direct area, but still in the marine industry).
...

• Grease (including vaseline) is not advised on any electrical connections as it is an electrical inhibitor. When it warms it becomes more viscous, can flow into the terminal and lead to increased resistance. This is particularly an issue on higher current connections (i.e batteries). If a waterproof connection is required, use any one of the suitable methods designed for the job. If corrosion protection is required, also use the right method (and materials) for the job. In fact, the proper grease is a code or manufacturer requirement for certain things here (US). We're just going to disagree. I've done the salt spray chamber testing to be sure of this. Grease is not an insulator (inhibitor?) if the contact pressure is correct (in certain high voltage/low current applications, that is different). The grease is pushed out of the contact zone and it excludes air and water. But yes, not everyone agrees.
• Heat shrink is not suitable for strain relief. It's purpose is electrical isolation and assisting with corrosion protection. If strain relief is required, this should be mechanical on the cable, not at the terminal. Yup. But I would say both, particularly in the case of soldered connections between wires of different gauges. It provides some support right there. Just a few inches of unsupported wire can vibrate enough to crack over time. Of course, you will heat shrink it anyway in most cases.
• Scotch-locks are the work of the devil. Anyone who has them should throw them all away immediately and advise anyone else to do the same. Oh yeah! So many ruined wires.
• Wago connections are hard to beat for cost-effective, efficient, long-lasting, low current connections in dry areas.

I stand by my comment regarding scotch-lock terminals... Yes!

See above.

One of many contact greases:
No-Ox-Id

 

[Hydrozoan]

... I stand by my comment regarding scotch-lock terminals...

I do not doubt it, and shall never mention them again! But where do you stand on the issue of two wires in one crimp?

 

[KompetentKrew]

You can buy heat shrink with a form of glue inside that will give a sealed finish, not suitable for continuous immersion but better than vaseline. I'll find a link later.

Don't set them off!

Previous thread: What heat-gun for solder-seal connectors?

 

[Moodysailor]

I do not doubt it, and shall never mention them again! But where do you stand on the issue of two wires in one crimp?

I did my apprenticeship in a BS, then ISO workplace, at that time we made our own electrical harnesses and panels. I was also in the first group of people in the UK to be certified as an ABYC marine electrician. So my views should be quite linear on this, in that one terminal - one wire.

But I also accept there are times when it is acceptable or necessary to put two wires into one terminal. My preference, if it allows, are piggy-back terminals though

I am my own paradox ?

Merry Christmas all

 

[Moodysailor]

See above.

One of many contact greases:
No-Ox-Id

I think we are on the same page here, as I'm an advocate of using the correct method and equipment for the job. So, specialist contact grease or something that you mention (manufacturer requirement) would definitely be a case where this is the right thing to do.

My comment was in the context of general greases (the type one typically might have aboard) - vaseline, lithium, etc. Here is an extract from Mr. Ed Shurman. Ed was my ABYC instructor, and was (possibly still is) the curriculum director for the ABYC. The odd nuance aside, when it comes to marine electrical standards, the ABYC are hard to beat IMO.

"The problem here is that, depending upon the grease itself and its actual melting point, you can create a situation where the grease will liquefy and act like a penetrating oil. It won’t take much heat. For example, Vaseline petroleum jelly, which many people use for this purpose, has a melting point just slightly higher than normal body temperature of 98.6 deg. F. On a hot summer day, the temperature surrounding your batteries will reach that temperature quite easily. The white lithium on the other hand has a melting point of about 360 deg. F -- which is still achievable on a hot summer day while pulling a heavy electrical load through the terminal.

The next phase of the problem is that the liquefied grease will penetrate down between the battery post and the inside of the terminal clamp. As the grease (now a liquid) continues to heat up between the post and the clamp, it will eventually oxidize and turn into a rather good insulator, the last thing you want at a battery post! The nasty part of all of this is that it is totally invisible, so there won’t be any visual clue like corrosion that any problem exists. If this problem goes unnoticed for a while, you will eventually lose electrical power, obviously a problem. "

 

[Hydrozoan]

... But I also accept there are times when it is acceptable or necessary to put two wires into one terminal. My preference, if it allows, are piggy-back terminals though

I am my own paradox ?

Merry Christmas all

Thanks - I thought that might be your answer. As to the slight paradox, I think you may refer to it as informed pragmatism.
A peaceful and merry Christmas to you and everybody here, too.

 

[John the kiwi]

My Contract electrician of 20 years on automation projects executed in 65 sites in two countries supplies and installs terminal strips with wago style connectors.
These industrial types don't have a finger lever, but an aperture where if you insert exactly the right tool, the spring clamp will open/release the wire and on removal will clamp it down. His argument is that screw terminals, even after initial tightening can and do lose their grip through repeated thermal cycles whereas spring clips keep on gripping.
Thousands of Input/output connections operating over 65 plants over many years and i have to say that I cant recall a single help call related to a poor wiring contact. ( I am the guy that gets the calls!)
On my boat I use a mix of solder joints with heat shrink, crimped connections and wago connectors. I love the wago connectors but only for locations that you know will stay totally dry as i don't know a way of waterproofing them. Wago connectors are definitely easiest way to join one to many.

 

[Hydrozoan]

... These industrial types don't have a finger lever, but an aperture where if you insert exactly the right tool, the spring clamp will open/release the wire and on removal will clamp it down. His argument is that screw terminals, even after initial tightening can and do lose their grip through repeated thermal cycles whereas spring clips keep on gripping. ...

I have previously recommended that type of sprung Wago block (261-106/341-000 | Wago PCB Terminal Block, 6mm Pitch | RS Components (rs-online.com)) for fine instrument wires, having used one on a nest of such with short tails in a cramped location. I had some initial reservations - I incline to a type of 'puritanism' if something seems just too easy compared with traditional alternatives - but it has never given trouble.

 

[boomerangben]

I believe that the wago connectors themselves have no certified tension resistance so need to be housed in one their proprietary boxes which have cable grips. Love them for 240v but the boxes are quite bulky so perhaps not so convenient on board.
WAGOBOX Junction Box | Wago_Connectors (51008319)

 

[smithy]

I have previously recommended that type of sprung Wago block (261-106/341-000 | Wago PCB Terminal Block, 6mm Pitch | RS Components (rs-online.com)) for fine instrument wires, having used one on a nest of such with short tails in a cramped location. I had some initial reservations - I incline to a type of 'puritanism' if something seems just too easy compared with traditional alternatives - but it has never given trouble.

Iv'e got one of these, twelve pole I think, for connection of the mast wiring. As I take the mast down every year it makes life so much easier.

 

[wizard]

I have previously recommended that type of sprung Wago block (261-106/341-000 | Wago PCB Terminal Block, 6mm Pitch | RS Components (rs-online.com)) for fine instrument wires, having used one on a nest of such with short tails in a cramped location. I had some initial reservations - I incline to a type of 'puritanism' if something seems just too easy compared with traditional alternatives - but it has never given trouble.

Have used those over the years for radar installations and mast lights with no problems at all - providing you always use tinned cables.

 

[Kilo]

Don't set them off!

Previous thread: What heat-gun for solder-seal connectors?

This is similar to the solder connections but just heat shrink....to shrink I use a gas soldering iron with the tip removed:
Adhesive Lined Heat Shrink Tubing | Hilltop Products Ltd

 

[Beneteau381]

I think we are on the same page here, as I'm an advocate of using the correct method and equipment for the job. So, specialist contact grease or something that you mention (manufacturer requirement) would definitely be a case where this is the right thing to do.

My comment was in the context of general greases (the type one typically might have aboard) - vaseline, lithium, etc. Here is an extract from Mr. Ed Shurman. Ed was my ABYC instructor, and was (possibly still is) the curriculum director for the ABYC. The odd nuance aside, when it comes to marine electrical standards, the ABYC are hard to beat IMO.

"The problem here is that, depending upon the grease itself and its actual melting point, you can create a situation where the grease will liquefy and act like a penetrating oil. It won’t take much heat. For example, Vaseline petroleum jelly, which many people use for this purpose, has a melting point just slightly higher than normal body temperature of 98.6 deg. F. On a hot summer day, the temperature surrounding your batteries will reach that temperature quite easily. The white lithium on the other hand has a melting point of about 360 deg. F -- which is still achievable on a hot summer day while pulling a heavy electrical load through the terminal.

The next phase of the problem is that the liquefied grease will penetrate down between the battery post and the inside of the terminal clamp. As the grease (now a liquid) continues to heat up between the post and the clamp, it will eventually oxidize and turn into a rather good insulator, the last thing you want at a battery post! The nasty part of all of this is that it is totally invisible, so there won’t be any visual clue like corrosion that any problem exists. If this problem goes unnoticed for a while, you will eventually lose electrical power, obviously a problem. "

A serious battery manufacturer, they recommend using Vaseline.

Know How to Maintain Your Battery - Tips by Exide

 

[thinwater]

A serious battery manufacturer, they recommend using Vaseline.

Know How to Maintain Your Battery - Tips by Exide

I think Moodysailor nailed it. The right product is a higher-melting contact-specific grease, but Exide figures the only thing a DIY has is Vasoline. They say "never grease" because there are a wide range of products, and some of the cheap ones are prone to oxidizing.

Perhaps the most common problem is not cleaning the studs and clamps/rings every time a new battery is installed. Clean and tight are the watchwords for connections, and batteries always exhale some acid.

 

[Beneteau381]

I think Moodysailor nailed it. The right product is a higher-melting contact-specific grease, but Exide figures the only thing a DIY has is Vasoline. They say "never grease" because there are a wide range of products, and some of the cheap ones are prone to oxidizing.

Perhaps the most common problem is not cleaning the studs and clamps/rings every time a new battery is installed. Clean and tight are the watchwords for connections, and batteries always exhale some acid.

I dont think he did. The manufacturer is quite specific about Vaseline and trying to read a conclusion in to what they say to suit a point of view? hmmm.