This discussion is locked.

You cannot post a reply to this discussion. If you have a question start a new discussion

Using Connection Strip with Ferrules

Former Community Member over 5 years ago

When connecting flexible wires using connection strip with screws it is recommended that one uses cord end sleeves or ferrules. What I realized if I connect two ferrules (1 In and 1 Out) the Insulation Jacket of ferules will not sufficiently enter the hole . and installation will end up as the attached figure. I am wondering if such connection is acceptable.

Note: in most cases I have 2x2.5mm2 Flex Wires In using Twin Ferrule and 1x2.5mm2 Flex wires out using single ferrule and I am using 10mm2 Connection strip

Another question is it acceptable to cut a little bit from the crimped ferrules so that they will enter sufficiently.

0 Zoomup over 5 years ago

As long as the connection is inside an insulated enclosure or earthed metal enclosure then all should be o.k. There is not much metal showing and a British Standard finger can't gain access to a live part. Still, this connection should not be exposed to touch. I can't see anything wrong in reducing the finger length of a ferrule as long as the connection remains mechanically and electrically sound.

Z.
Cancel
Vote Up 0 Vote Down

Cancel
0 tattyinengland over 5 years ago

Please use din rail terminals. These will take ferrules cables perfectly. Please also use a proper ferrule crimper. (Not pliers or the screw terminal screw). You'll also need a blank end to insulate the last din rail terminal and a stop end. such as:
Weidmuller EW Series ATEX End Bracket. and Wago 2002 Series End & Intermediate Plate

Kind Regards

Tatty
Cancel
Vote Up 0 Vote Down

Cancel
0 AJJewsbury over 5 years ago

Personally I always use "bootlace" ferrules - i.e. the ones without any kind of insulating sleeve. The wires then terminate just like solid core wires.

When you say "the Insulation Jacket of ferules will not sufficiently enter the hole" are you suggesting that there's then insufficient conductor under the screw to make a proper connection? Is so then I would say that was indeed a problem. If it's just a matter of a gap in the insulation, then I don't see a problem - the system is likely only needed to be IP2X (finger proof) and probably not even that if it's not accessible without a tool.

- Andy.
Cancel
Vote Up 0 Vote Down

Cancel
0 Former Community Member over 5 years ago

Thanks for your reply. I was concerned about the insulation and thanks for your opinion.

Besides, I know it is a good practice to encase IEC 60288 Class 5 and class 6 finely stranded flexible conductors with ferrules, I want to know if there is a mandatory regulation in BS standard other than BS EN 60079 (explosive atmosphere) that mandates the use of ferrules for IEC 60288 Class 2(Stranded), Class 5 and class 6(Finely Stranded) conductors.(Inside Panel Boards and in Junction boxes)
Cancel
Vote Up 0 Vote Down

Cancel
0 AJJewsbury over 5 years ago

I want to know if there is a mandatory regulation in BS standard other than BS EN 60079 (explosive atmosphere) that mandates the use of ferrules for IEC 60288 Class 2(Stranded), Class 5 and class 6(Finely Stranded) conductors.(Inside Panel Boards and in Junction boxes)

For things covered by BS 7671 (there are different standards for the wiring of 'machines' etc.) there's no specific demand for ferrules but there is general demand for 'multiwire', 'fine wire' and 'very fine wire' for the conductor to be "suitably treated" to avoid the inappropriate spreading of the individual wires (regulation 529.9.1). Depending on the situation and type of terminal, that allows for any number of options - in some cases just twisting the strands might be sufficient - in other cases ferrules would seem a better choice. With some terminals it might be that the strands can spread but are still held properly in the terminal - so nothing at all might be needed. The only method that's specifically mentioned is the soldering (tinning) of the ends of fine and very-fine wires - which is prohibited when using screw terminals are used or where there can be movement between the soldered and unsoldered parts of the conductor (regs 529.9.2 and 529.9.3)

- Andy.
Cancel
Vote Up 0 Vote Down

Cancel
0 Former Community Member over 5 years ago

Thanks AJJewsbury and I appreciate your help
Cancel
Vote Up 0 Vote Down

Cancel

Using Connection Strip with Ferrules

Weidmuller EW Series ATEX End Bracket. and Wago 2002 Series End & Intermediate Plate

Join us to get the best from IET EngX.

Community Rules & Guidelines