Recducing pins/lugs

[Dannyg8810]

just a bit of info needed guys

Iv just ordered a swa lug crimped that does 6mm-120mm as iv a job to re terminate some cables into a main switch on a board as these are currently 70mm swa with cores cut off.

Will the lug have a reduced ccc?

 

[ipf]

Why such a big cable? (volt drop, maybe)
What size is the main switch?
Is it viable to install a manufactured adaptation for the main switch?

 

[davesparks]

You’d have to ask the manufacturer of the reducing lugs to be sure

 

[Dannyg8810]

Why such a big cable? (volt drop, maybe)
What size is the main switch?
Is it viable to install a manufactured adaptation for the main switch?

Im unsure why as seem overkill to me it’s on a 100amp Mccb at the main panel.

 

[ipf]

Im unsure why as seem overkill to me it’s on a 100amp Mccb at the main panel.

Why ask the question without details then?...Lug it and connect, if it's a 100amp MCCB.

 

[Dannyg8810]

Why ask the question without details then?...Lug it and connect, if it's a 100amp MCCB.

Why ask? Because I am ,iv never had to use these before is it an issue asking in general?

The question was regarding ccc of the lugs also not the ins and outs of the installation

 

[benji]

are you saying its a 120mm lug with 6mm hole or a crimper that crimps 6mm to 120mm lugs

 

[Richard Burns]

A cable lug from a reputable manufacturer that is crimped using a suitably matched cable crimper on the correct size cable will not reduce the current carrying capacity of the circuit.
Any well made lug (as opposed to cheaply or poorly made lugs) will be made of copper and have a csa equivalent to the cable core designed to be terminated.

 

[Dannyg8810]

are you saying its a 120mm lug with 6mm hole or a crimper that crimps 6mm to 120mm lugs

70mm cable ,crimper is capable of 6mm to 120mm

 

[Dannyg8810]

A cable lug from a reputable manufacturer that is crimped using a suitably matched cable crimper on the correct size cable will not reduce the current carrying capacity of the circuit.
Any well made lug (as opposed to cheaply or poorly made lugs) will be made of copper and have a csa equivalent to the cable core designed to be terminated.

thank you for that info mate ,I’m just awaiting for info from SWA was just seeing if u could find out on here in meantime

 

[Richard Burns]

I must apologise I have failed to notice the title of your post and was going by the text only and not reading the implication of terminating a 70mm² conductor into a 100A MCCB, although 70mm² would fit with some manufacturers.
I was discussing lugs and not reducing pins, a reducing pin will lower the current carrying capacity at that point as there will be a section of the pin that is at the reduced cross sectional area that is not in continuous contact with the connector terminal. The actual csa can be determined from the diameter of the reduced pin which may be up to three sizes lower than the incoming cable.
Obviously when using a reducing pin the device terminals will be able to take a conductor that can carry at least the maximum rating of the device and so this loss of CCC will not affect the safety of the equipment.

 

[ipf]

Why ask? Because I am ,iv never had to use these before is it an issue asking in general?

The question was regarding ccc of the lugs also not the ins and outs of the installation

Sorry to upset you, pal, but it seems I misunderstood your question...in fact, I'm still trying to get my head around it.
Thanks Richard B.
As I see it now, you've a 70mm cable from a 100amp MCCB to a DB main switch, in which case the cable is the overkill, unless length of run brings in a volt drop matter.
The reduced pin connection rating depends on that of the MCCB not the cable, in this instance.

I remember a coming across a situation with a similar size cable feeding a much smaller load but it was 350m away, hence the cable size. It was terminated after reducing to 10mm using nut and bolts in the DB....very well taped up, though. Gypsies did a live cut and made off with about 120metres of the stuff.

 

[Toneyz]

We had a sixth form building at a school once that was fed with 180mm 100A supply that was hard getting in MCCB panel main switch load end all we could think of was at some point a thought of having a new supply installed in the sixth form and feeding back.

 

[Dannyg8810]

Sorry to upset you, pal, but it seems I misunderstood your question...in fact, I'm still trying to get my head around it.
Thanks Richard B.
As I see it now, you've a 70mm cable from a 100amp MCCB to a DB main switch, in which case the cable is the overkill, unless length of run brings in a volt drop matter.
The reduced pin connection rating depends on that of the MCCB not the cable, in this instance.

I remember a coming across a situation with a similar size cable feeding a much smaller load but it was 350m away, hence the cable size. It was terminated after reducing to 10mm using nut and bolts in the DB....very well taped up, though. Gypsies did a live cut and made off with about 120metres of the stuff.

No worries IPF

Basically the cores have been cut to allow cables to fit in the switch
The run is not massive so won’t be due to volt drop ,this was originally installed overkill as the use of the building may not yet of been known.

I just wanted to know if anyone knew what current the lugs are rated etc....

 

[Richard Burns]

Hair cutting the cores to remove strands also reduces the current carrying capacity of the cable so I would not worry to much about using a reducing pin as it will have less effect than cutting off one of the strands of a core.
For example jointingtech has reducing pins for 70mm² cable that have a reduced pin diameter of 8mm.
From this A=r²π = (8/2)²*3.14159 = 50.3mm²
so your CCC has perhaps changed from 232A to 184A (sp ref C multicore) for a 100A protective device, no real problem there.

 

[Dannyg8810]

Hair cutting the cores to remove strands also reduces the current carrying capacity of the cable so I would not worry to much about using a reducing pin as it will have less effect than cutting off one of the strands of a core.
For example jointingtech has reducing pins for 70mm² cable that have a reduced pin diameter of 8mm.
From this A=r²π = (8/2)²*3.14159 = 50.3mm²
so your CCC has perhaps changed from 232A to 184A (sp ref C multicore) for a 100A protective device, no real problem there.

The client wants these lugging so this is required even if there’s no real issue

 

[Richard Burns]

No, hair cutting the cable is the problem, the solution is to use reducing pins.
There is an issue with the hair cut, there is not an issue with the reducing pins.
It may be possible to prove the hair cut is not detrimental but it is bad practice and could have caused damage to other strands and further weaken the cable.

 

[Dannyg8810]

No, hair cutting the cable is the problem, the solution is to use reducing pins.
There is an issue with the hair cut, there is not an issue with the reducing pins.
It may be possible to prove the hair cut is not detrimental but it is bad practice and could have caused damage to other strands and further weaken the cable.

Sorry I misread what you said.

Thanks for the advise