Fork terminals

[kingpb]

Interesting topic. I agree that you are adding a whole bunch of failure points, plus a whole lotta labor costs.

I'd have to say I'd probably pigtail solid to the stranded if needed in lieu of crimping on fork connectors.

Many (many) years ago we used to put stranded under a screw by stripping the end long, then trim the end such that some (1/4" or so) of the insulation was left in place to help keep strands from fanning out when tightening the screw. No idea if that was right or wrong but it worked. Thankfully due to statue of limitations I can't be sued either way. :angel:

 

[jrannis]

Interesting topic. I agree that you are adding a whole bunch of failure points, plus a whole lotta labor costs.

I'd have to say I'd probably pigtail solid to the stranded if needed in lieu of crimping on fork connectors.

Many (many) years ago we used to put stranded under a screw by stripping the end long, then trim the end such that some (1/4" or so) of the insulation was left in place to help keep strands from fanning out when tightening the screw. No idea if that was right or wrong but it worked. Thankfully due to statue of limitations I can't be sued either way. :angel:

I was taught this way and think nothing of wrapping stranded wire around a device terminal.
I do have a bit of a problem with solid #12 lately. I went back on a residential apartment job to design some controls and noticed that about 75% of the solid wire terminations on switches were loose. As soon as I removed the switch, I could see the lights flicker. ALMOST EVERY STINKING TIME. 50 out of the 60 I looked at were all loose. Most of the grounds came completely off of the device ground screw.
I am not a big fan of solid wire or bare ground conductors so, this was a nightmare project for me.

 

[dereckbc]

In my opinion the fork terminals just add another point of potential failure.

How so Bob?

Not trying to start an argument but after 33 years in electric utility and telecom sectors installation standards and engineering practices forbid solid wire and binding screws to be used because of the high risk of failure. Most of that risk is contact resistance and heating compounding the failure and fire risk. If I were to see forks or rings used with proper termination tools and methods I bet that person wears both a belt and suspenders to hold his pants up, and does utility work.

 

[iwire]

How so Bob?

How so?

You are literally doubling the amount of terminations.

Assuming the equipment terminals are listed for use directly with the conductors the addition of crimp on forks, rings, pins etc. .... even with the proper tools can only decrease the reliability of the entire installation.

I will guess that I will be told proper installation of these crimps will make them reliable, well the same person that could correctly and properly make a crimp could also do the same with a screw connection.

It is my opinion that pins, forks and rings are often added only out of tradition and because they look pretty.

 

[iwire]

Sure does. Making a splice in a junction box increases the # of potential points of failure.
Let's forbid junctions of any kind between OCD and load.

I am not saying lets forbid any junctions. I saying adding more needless ones is not a good plan.

Truth be told I have seen way more failures at wire connectors , and at solid wire connections to devices.

And if you are like most of us you see more wire connectors and solid wire connections to devices in general.

I am not saying I never use crimps, I just do my best to avoid it. Just as I don't needlessly add junction boxes to a home run.

 

[don_resqcapt19]

SNAP SWITCHES (WJQR)
Terminals of the wire-binding screw, setscrew, or screw-actuated back-wired clamping types are suitable for use with solid building wires unless otherwise indicated either on the device or in the installation instructions. Terminals of a flush snap switch are permitted for use with Listed field-installed crimped-on wire connectors or an assembly, if so identified by the manufacturer.
...

From RTRT....

Terminals of the wire-binding screw, setscrew, or screw-actuated back-wired clamping types are suitable for use with both solid and stranded building wires.
Terminals of a receptacle are permitted for use with certified field-installed crimped-on wire connectors or an assembly, if so identified by the manufacturer.

 

[dereckbc]

Bob just want to make sure we are on the same page. I am referencing using stranded wire, not solid.

 

[PetrosA]

News to me, most have captive screws so I am really doubtful about ring terminals.

Just cut a slot in the end

???

just a thought.. twist strands "counterclockwise" first.

pulls tight around screw, doesn't fan.

I was taught this years ago when doing lamp repairs. It works with both regular strands and fine strands.

I personally don't like seeing stranded wrapped around a screw terminal since most times it's fanned out and a bunch of strands are poking out as most guys don't know to twist backwards. If the device has pressure plate terminals, I have no issues with using stranded. If the device only has screw terminals and a crimped fork can fit, I'd rather see that. Makes replacing the device a lot easier, too.