DougAles
Member
- Location
- Green Bay, WI, USA
Crimp terminal installation - what's wrong with this picture?
- Thread starter DougAles
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J.P.
Senior Member
- Location
- United States
Slightly overexposed? The bottom one may be out of focus a bit...........
- Location
- Massachusetts
Nothing that can be determined from the picture.
We would need the model and brand of the crimps and the terminals.
PetrosA
Senior Member
- Location
- Lancaster, Pennsylvania
Not true. It's never ok to use the nest for uninsulated terminals on an insulated terminal, regardless of manufacturer.
- Location
- Massachusetts
I will stick with not being able to judge without seeing instructions.
Saying 'never' is something I try never to do.
PetrosA
Senior Member
- Location
- Lancaster, Pennsylvania
DougAles
Member
- Location
- Green Bay, WI, USA
Thank you for responding to my question. Here is the additional information you requested.
The terminal is a Sta-Kon brand from my employer, Thomas & Betts. It is a vinyl insulated terminal.
The tool is Thomas & Betts part number WT112M.
As a hint, there are three concerns I have with the crimp that was done to this terminal. One has been correctly identified.
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- Location
- Massachusetts
Does this help?
No, you are showing one tool in a world of millions.
I suspect the instructions are not being followed, I don't really feel like looking up the parts.
My point was, and I suspect yours was too, that the right tool has to be used in the right way with the right crimp.
PetrosA
Senior Member
- Location
- Lancaster, Pennsylvania
Aside from the wrong nest being used for the crimp, the insulated sleeve wasn't crimped over the wire's insulation for strain relief. The third issue is eluding me. Could be wire size vs. terminal size or incorrect stripping length, but I can't tell that from this photo.
DougAles
Member
- Location
- Green Bay, WI, USA
Thank you PetrosA. I wouldn't set you up with a wrong wire size unless I had the wire gauge showing in the photo.
The concerns I have with the crimp in the original photo above are:
1) Crimping of insulated terminals needs to be done in the insulated nest of the tool.
2) The first of two crimps needs to be in a different location, closer to the terminals tongue.
3) The second of 2 crimps needs to be done over the wires insulation so wire strand strain from vibration and wire movement occurs in the wire insulation protected portion of the wire.
I'm in the field much of the time and have come across crimping done like the one in the above photo.
When a crimp terminal manufacturer submit's their terminals to a UL testing lab for UL approval the lab must follow the instructions specified in UL486A/B. The UL instructions are not brand specific.
Did you find this helpful? Are you going to change the way you are crimping terminals? Would you like to see more posts like this?
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- Location
- Massachusetts
What do you mean 'not brand specific' for us in the field we need to make sure the crimper we are using is the type needed for the terminals we are using. Right?
Yes this is helpful. Thank you for posting.
I would like to see the instructions that are sent out to the feild with the crimps that require the steps you suggest.
I will be honest, I have been doing this 30 something years and have never heard of the plastic coating called a strain relief. I also have serious doubts it can perform as a strain relief.
I always assumed we should be wiring in ways that no strain is placed on terminals.
stevenje
Senior Member
- Location
- Yachats Oregon
Agreed. I thought the plastic insulation on the crimp connector was just what it indicates, an insulator to keep that portion of the crimp terminal insulated from other sources of power or grounds.
- Location
- Placerville, CA, USA
- Occupation
- Retired PV System Designer
Some insulated terminals have a thin metal section under the insulation beyond the main barrel. Its purpose is to crimp around the unstripped portion of the wire as a strain relief. In general the terminal insulation alone cannot serve as a strain relief as it will not hold its deformed state very reliably.
Tapatalk!
Tapatalk!
DougAles
Member
- Location
- Green Bay, WI, USA
Thank you for your question, allowing me to clarify. The instructions UL provides for performing the terminal testing in UL486A/B are not brand specific.
You are welcome.
If I did this correctly, there should be two attachments to my reply. I just took two photos with my phone showing the front and back of the packaging of the part number WT112M tool in the original photo. This packaging has limited space for writing, however it includes a photo to show the profile of a correctly installed terminal. I'd like to see more detailed instruction on the packaging, however, even with these instructions I'm a proponent of my team that interacts with electricians use opportunities like demonstration classes, wholesale distributor counter days, attending and presenting at trade schools, electrical inspector meeting & other events to show installation instructions like this. Also, Thomas & Betts invested a lot of resources in four trucks, and four dedicated employees to criss-cross the country and focus on lugs, terminals and tooling. Perhaps someone here has seen one of these trucks?
I can assure you, we are trying to get the word out. Packaging, websites, classes, trade show, and counter days do not reach eveyone. This very post at this forum is a new idea. I'm testing the water if you will, to see if manufacturer non-sales oriented information sharing will be accepted.
In my discussions with the person that works at the certified UL testing lab, its not pull-out but vibration and wire movement protection, two additional forms of strain, that the second crimp aids in the performance of the connection. Think of the individual strands of the wire. Take one strand and bend it back and forth a few times in your hand. The strand will soon break. Now put this same force on the insulated portion of the wire. This second crimp over the insulated portion of the wire helps in this manor.
Again iwire, thank you for your taking your time to read and respond to my post.
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DougAles
Member
- Location
- Green Bay, WI, USA
Thank you for posting your observation. I'll do my best at a simple, short anser. You just described an nylon insulated terminal. A vinyl insulated terminal keeps its crimped shape. The nylon has different characteristics, some that are advantageous to vinyl. However, the insulation tends to pop-up over time. So the sleeve between the terminal and insulation is added. As you observed, one purpose of this sleeve is to provide the same benefits of the second crimp of the vinyl insulation.
DougAles
Member
- Location
- Green Bay, WI, USA
PetrosA
Senior Member
- Location
- Lancaster, Pennsylvania
Terminator,
Just an observation - the picture instructions on the pliers' packaging would suggest that for insulated terminals (forks, rings or disconnects) a single, centered crimp is all that is required. Maybe speak to the graphics department about this to make it clearer or correct this, as needed.
It's an interesting battle you have ahead of you. We've debated to death on this forum whether or not to pretwist wire nutted connections plus all the other pros and cons of them, but crimped connections are generally not even discussed. I'd even go further than you and say that most electricians who use that style of crimping pliers uses the wrong nest on insulated terminals because they feel that it makes a better connection - kind of like tightening breakers and busbars "farmer tight." I fear it will be very difficult for you to change their habits.
Just an observation - the picture instructions on the pliers' packaging would suggest that for insulated terminals (forks, rings or disconnects) a single, centered crimp is all that is required. Maybe speak to the graphics department about this to make it clearer or correct this, as needed.
It's an interesting battle you have ahead of you. We've debated to death on this forum whether or not to pretwist wire nutted connections plus all the other pros and cons of them, but crimped connections are generally not even discussed. I'd even go further than you and say that most electricians who use that style of crimping pliers uses the wrong nest on insulated terminals because they feel that it makes a better connection - kind of like tightening breakers and busbars "farmer tight." I fear it will be very difficult for you to change their habits.
DougAles
Member
- Location
- Green Bay, WI, USA
- Location
- Massachusetts
- Status