Connecting Two Legs in One Terminal

well what power terminals??

could u elaborate please??

The connection under the pressure of one bolt can be affected by conductors that differ in circumference. The larger conductor might take the pressure, shielding it's neighbor, the smaller conductor, which will suffer from poor connection syndrome.

This can happen even with same-sized solid or stranded conductors, and mixing of solid and stranded, or stranded of different designs, and depending on the design of the terminal and the skill of the workman.

Other reasons will be related to load value certainty, maintenance issues (since both wires will be affected if terminal must be loosened), the possibility of dis-similar metals (aluminum with copper) improperly installed, etc.

Your mind is now headed in the right direction, as these are only a few of the reasons available.

Hello mkarolam,

I have done this in junction boxes, which are designed to have two wires under one screw. But both wires were the same size and twisted together. And these junction boxes had a screw on 'lid' which covered and helped secure the wires as well.

I would not do any twisted or single wire open junction box connections at all.

Single core and multi-filament wires should not be mixed and or joined like this. While the larger core is held tight, there could be just a couple of filaments held secure. Not on! It is a fire hazard.

Where they would get damp of any kind, or outside....... Even indoors it is likely for these to attract condensation, and or pests.

A connection with open connectors should never be made and buried in a wall, concrete, mortar etc.

There is simply no need to use these connectors other than low power installations perhaps. But, if you run your wires properly, this 'connector ----shortcut' type of work will not be needed.

With domestic wiring, running wires in a conduit should always be a matter of course and the correct way of working. And this should be the way to work on any 3-phase installation without exception.

Take care, and happy holiday................

Look at how the connection is listed. If it is listed for two conductors, get new consultants. Some are some are not. Generally if there is more than one conductor the torque specification goes up. The key though is how the product is listed. For terminal blocks generally the the listed wire sizes are stamped into the material. Split bolt type connectors are usually listed for two conductors. This is because when there is three, the connector will not be contacting one of them, and tightness cannot be assured. Once again check the manufacturer. In the USA I would refer you to NEC article 110.3(B) which states "Listed or Labelled equipment shall be installed and used in accordance with any instructions included in the listing or labelling."

Mr.Mkariolam,

Please correct it as Lug (Terminal socket) not Leg. You can connect two Lugs to one terminal of the same phase of the same line if there are multiple cables as per the Load. (For Example: if 2 runs of 4 core cables starting from panel to equipment). But take care while connecting as , each Lug to either side of the Bus bar with flat and spring washer and tight to required torque.

There are a few things that require clarification.

1. By legs; do you mean 2 different phases or 2 conductors of the same phase ( as in a multiple cable run to the same equipment)
2. By terminal; do you mean lug ? If so; use a lug designed for multiple conductors and ensure that there is enough surface contact to prevent overheating.

Get back to the <...consultant...>, and ask why. Telephone?