I had a couple of outlets go out in my house. I went to change them and to my suprise I found Scotchlocks instead of wire nuts. I have been a comercial/industrial electrician for about 14 years or so and have never seen this. I do know sometimes residential wiring gets done a little half horsed so I called 3M thinking maybe this was sometimes practiced 30 years ago but of course 3M said 12 volt only. I plan to change it all out but wanted to know if anyone here has seen this before, other than automotive anyway.

You mean them dodgy things they use to "tap" into wiring looms in cars?

I've never liked the use of them even in the application they were designed for, let alone in a house!

Those be the things. i have used them in various vehicles of mine but never on 120v. Heres a pic-

http://site.innovationestore.com/images/family.php?id=3m-scotchlok-electrical-idc-804

Yeah,
That's them.
Designed for those that can't use basic hand-tools like strippers and screwdrivers.

In a home? Never.
Mid -late 80's, thats all we used for our temp lights. Run the NM and strip back at the bulb location and use these with the pig tails.

We use them in continuous row lighting applications, and never had a failure.

Model 567 is rated 600V general purpose and 1000V in signs and fixtures, #12 Run and #18 Tap.

They're a lot faster than to cut, strip, and wirenut all the connections

3M calls them "insulation displacement connectors"

I see those in homes all the time and they always give trouble.

I see them often, inside flourescent light fixtures for the ballast connections. But, I have never seen them in general wiring, though.

20 years ago, somebody was marketing connectors like this for ballast replacements. I haven't seen them since.

Those "no-box" AMP NM connectors they use in modular homes are also IDC connections. You can bury them behind the drywall according to U/L. There was a time when AMP was saying you could use them in general wiring, fished etc. The code didn't change (334.40(B)), only the marketing.
It always smelled pretty fishy to any inspector I talked to. I talked to an AMP rep about it and he sent me a few. (I may still have them around here somewhere) They are not much different than the Scotch Lock in my opinion. The last time I saw an ad they were only targeting modular homes and citing 552.48(N) and similar.

OK, so I guess the general concensus is that they aren't for home wiring but others have seen them. This house was built by the home owner himself and for the most part is built like a brick sh-t house. Very sturdy, but the wiring is where he lacked. To bad for me but I will be changing them. Thanks, guys.

Yea, I've seen that before...in the same house where the previous occupants replaced a 15-amp breaker with a 30-amp one, melting the ground wire into the hot wire and burning it away, leaving the ground hot leaving the panel (if that gives you any idea at their skills. They stunk at plumbing, carpentry, and drywall work too.).

Those type of Scotchloks are not intended for solid wire, only stranded wire. (The other type that is intended for solid wire is for telephone use).

I'm wondering if these are the same things we call "wago"s. That may be a brand name. Same principle as back-wired recepts, in my opinion. Fast and easy, but likely to loosen over time and then cause arcing, etc. We used them (supplied by contractor) on university housing ~3 years ago. No fires yet, as far as I know, but I still would never use them by choice.

No, they are not the same as "wagos".

The connectors being discussed have a piece that slices through the insulation; this 'knife' is then supposed to wedge itself on either side of the wire, making contact.

They're typically used in lighting applications, where they are used to tap off a #12 wire, to feed a ballast. I don't think I'd rely on them for any serious current, though.

"Wagos" , as well as the similar Ideal "In-Sure," work on a completely different principle, and have a far better record thant back-stab receptacles. Those connectors, however, are another discussion.

By the way a short look over the pond:

"Wagos" are the state of art in this millenium. Wire nuts and everything with any type of screws is regarded as antique because only the spring mechanism of a wago type connector is able to adapt to possible form changing of a copper wire. A German electrician rarely uses a screw driver to connect wires, he just "pushes in the wires", even on mcbs or neutral or ground bars.

"Scotchlocks" or alike have not been introduced into LV installations and are so far limited to cars.

On the other hand the Scotchlock like connecting principle is very much promoted and more and more used in industrial context, here called f.i. "QuickOn"(Phoenix Contact) or similar.

According to the data sheet for the Scotchlok™
Insulation Displacement Electrical
Tap Connector 560:



It says they do work with solid wire. This is for the blue ones; the red ones, like the one I saw, are designed for smaller-gauge wire (18-22 gauge wire).

Perhaps the biggest problem with these Scotchlok connectors is that you have to use the correct size for the wire you're tapping into to make a reliable connection. If you don't, expect problems.

Correct, Brian ... and there is a yellow one for joining two #12 wires.

Spec sheets aside, and despite the extraordinarily fine reputation of 3M , I have found the devices problematic with #12. That is, connections are often intermittent. It's possible that the blades are damaged during installation.

I restrict my use of them to light ballasts.