Temporarily connecting two wires together

[ajb]

Out of interest what do you guys use in American for high current connections, say a cooker for example ? Presumably screw terminals throughout ? I'm not sure wire nuts would apply anywhere near enough force to prevent heating for these kind of currents ?

If it's not something that plugs into a standard receptacle it's typically a dedicated circuit, so there's not much need for splicing unless you've renovated and moved the appliance or something.  Freestanding oven/cooktop appliances typically have a dedicated receptacle with a suitably rated plug.  Built-in cooktops or stoves might be permanently wired, I can't say I've every seen how one is installed.  Many permanently wired appliances come with wire nuts for making the connection between the branch circuit and their internal wiring, although you occasionally get Wago-style connectors.  Larger wiring, such as feeders, I've only ever seen done with set screw splices. 

Specialty equipment may have additional requirements or restrictions.  I recall hearing a while ago that ETC doesn't permit wire nuts to be used inside their Sensor racks--I think they require crimp splices--which makes sense when you have up to 96x20A circuits plus 200+A feeders terminating in a wiring space that's only something like 8" wide and 4" deep.

[yngndrw]

The largest current device is typically an electric oven/cooktop combination (Not counting electric whole house heaters which most people find too expensive to operate).  This is typically a 50amp, double pole, circuit, and uses #6 wire guage, usually stranded.  This is usually the largest gauge wire where a (large) wirenut is used.  Larger guage wires, such as service entrance wires, will use something like an Ilsco brand connector.  This is somewhat like an insulated terminal block with allen key set screws (grubs?).  Barrel crimps are also used, but require thick rubber splicing tape and electrical tape.

If it's not something that plugs into a standard receptacle it's typically a dedicated circuit, so there's not much need for splicing unless you've renovated and moved the appliance or something.  Freestanding oven/cooktop appliances typically have a dedicated receptacle with a suitably rated plug.  Built-in cooktops or stoves might be permanently wired, I can't say I've every seen how one is installed.  Many permanently wired appliances come with wire nuts for making the connection between the branch circuit and their internal wiring, although you occasionally get Wago-style connectors.  Larger wiring, such as feeders, I've only ever seen done with set screw splices. 

Specialty equipment may have additional requirements or restrictions.  I recall hearing a while ago that ETC doesn't permit wire nuts to be used inside their Sensor racks--I think they require crimp splices--which makes sense when you have up to 96x20A circuits plus 200+A feeders terminating in a wiring space that's only something like 8" wide and 4" deep.

Thanks both, interesting to know. The thought of a 50A wire nut scares me (And you must need fingers of steel to twist one of them on some 6 gauge wire) but it sounds like they are an option that are never really used.

[M. András]

I somtimes wonder when i see a typical american wiring job. Drilled copper bars with grub screws are one thing to terminate bunch of wires, if tightened enough it shears the solid core wires, if not it comes lose in no time. Spring type industrial connectors and din rail mounted connector blocks are better but you cant find those in residential buildings cos its expensive and no homeowner would pay for it.
However what i cant see is the use of crimped on ring terminals used with wire nuts its more secure and with proper spring washers it would never get lose, instead they losely twist the wire and sometimes the twist will untitwist beacouse of the direction which the nut is thightened. The most secure screw type connections are on the good quality mcb-s schneider electric acti 9 industrial breakers those can be thightened to a level without much effort that i basicly crimps an overhead aluminium cable those are usually multiconductor alloyed wires bundled together and pretty hard. Here i would get fired from my job if i use the method accepted in america for terminating wires for current carrying, for earthing purposes it can be used but you have to take care doing it otherwise it has to be crimped or secured with appropiate terminals mounted on the device itself.

[IdahoMan]

Should we just rename this Thread: "Wire Nuts"?

Still looking for ideas for temporarily connecting small wires.

[yngndrw]

Should we just rename this Thread: "Wire Nuts"?

Still looking for ideas for temporarily connecting small wires.

To be honest, for your temporary connections I'd just the lever Wago connectors:

• Works with both solid and stranded wire
• Quick and easy to use
• Do not damage or twist the wire
• Are insulated
• Can connect more than two wires together (They go up to 5 way)
• Handle a range of wire sizes (28-12 AWG)
• Are good for 600V and 20A
• Have a built-in test port

[LaurentR]

Do you Wago nuts have experience with the newer, smaller 221 type vs the more common 222?

[yngndrw]

I've only had experience with the 222 type but the 221's look good and have some good Feedback on Amazon, so I've purchased some 221's for the workbench. It looks like they go up to 12AWG which will be handy for power distribution.

It's worth noting that there's two ratings in the datasheet for them:
UL - 20A / 600V
ENEC - 32A / 450V

I have no idea why there are two different ratings, does it just depend on the amount of acceptable heating and the different standards use different thresholds ?

http://www.wago.com/media/221/downloads_2/221_series_overview_ext.pdf

[ajb]

Come to think of it, I wouldn't mind having a set of test leads that had Wago-style spring connectors on one end and bananas on the other, for those occasions when you want a temporary setup that can be knocked about a bit more than typical alligator leads can be trusted to handle.  More of an inline style would be preferable over the 222/221.  The 224 "service" connectors look about right for that, although they only go up to 16AWG.

[Monkeh]

Come to think of it, I wouldn't mind having a set of test leads that had Wago-style spring connectors on one end and bananas on the other, for those occasions when you want a temporary setup that can be knocked about a bit more than typical alligator leads can be trusted to handle.  More of an inline style would be preferable over the 222/221.  The 224 "service" connectors look about right for that, although they only go up to 16AWG.

Not quite what you're looking for, but for those who lack binding posts on power supplies and the like: http://uk.rs-online.com/web/p/4-mm-test-plugs-sockets/1814579/

[janoc]

What's wrong with one of these?



Way cheaper than Wagos.

[LaurentR]

It's worth noting that there's two ratings in the datasheet for them:
UL - 20A / 600V
ENEC - 32A / 450V

According to toolguyd, it's because the max usable US gauge is 12AWG, which is rated for 20A. As for the voltage difference... not that it would matter to most people.

[LaurentR]

What's wrong with one of these?

I am feeling all nostalgic now. These are very uncommon in the US. They carry them at renovation stores like Home Depot (there is exactly one size and they're an expensive novelty) but I have never seen them used at all. My electrician (who is French too and was also licensed in France) keeps bitching about improperly installed nuts being a major cause of fires in the US (I believe him - I have seen so many poorly installed nuts). He just switched to push-in Wagos :-)

[jonovid]

I have seen so many poorly installed nuts

reminds me of them US Twist-on wire connectors . 

[janoc]

What's wrong with one of these?

I am feeling all nostalgic now. These are very uncommon in the US. They carry them at renovation stores like Home Depot (there is exactly one size and they're an expensive novelty) but I have never seen them used at all. My electrician (who is French too and was also licensed in France) keeps bitching about improperly installed nuts being a major cause of fires in the US (I believe him - I have seen so many poorly installed nuts). He just switched to push-in Wagos :-)

Ah okay. Here it is the opposite - wire nuts are very uncommon, I didn't even know what it was until someone has mentioned it here in another thread some time ago. However, these "dominos" or "chocolates" are everywhere.