150mm Tri Rated

[Shakeout]

I have installed 150mm tri rated cables replacing old existing cables with loose crimps which were over heating.
and identified by a heat mapping report carried out on site.
The runs from the isolator to the contactor within the panel are very short, about 200mm and not straight, hence I have had to put a loop on each one. This was the only way to bring the tails onto the lugs square and straight. The originals were straight but very tight.
Its feeding a large 3 phase motor which sits at around 260 A once up and running. 400A BS88 overcurrent devices.
Connections are all good, just wondering if the single loop/circle Ive made with each tail may cause any problems.
Probably a silly question but thought it worth an ask with such large currents/tails
cheers

 

[LeeH]

260 is a baby!

It's no problem, just doesn't always look the part. 150mm is very large for 260A generally.

Tri is rated at 105degC and without looking you could have probably dropped down a couple of sizes.

 

[Shakeout]

I did wonder if it was oversized, Thought Id better stick to what was there already though.
thanks for the reply, cheers

 

[netblindpaul]

It's all well taking the temperature rating of the tri @ 105 which it is, but, are the connected devices rated @ 105, I doubt it.
They are probably 70 deg C rated, thus, you must size the interconnects for the installed cable size/rating to keep the running temperature down to the limit imposed by the connecting devices.
OP you mention panel, so MCC to EN 60439/61439, or panel under EN 60204?
This may have an affect on the cable rating due to the potential differences in allowable cable ratings for different installations methods experienced in the different standards.
Either way, BS7671 ratings are irrelevant, and the OEM ratings may be more relevant as long as they reflect the as installed state.