Minimum Distance From Tray Ladder 33 kV

Found this....

https://electricalnotes.wordpress.com/2011/04/22/minimum-electrical-clearance-2/

Good find, though these appear to be for non-insulated conductors. Caution in using this table is advised, since there appears to be no qualification on the application. For instance, ANSI Standards for 35kV class equipment include 3 BIL Ratings, 125kV, 150kV and 200kV crest ratings, covering anticipated switching surges and other typical events. For two of those ratings, the spacing is either 229mm or 330mm, for indoor or protected phase to phase spacing. For outdoor installations, 200kV BIL phase to phase spacing is generally taken as 914mm.

From experience with 35kV 1/c 500MCM Kerite insulated concentric neutral with overall jacket, one consideration we overlooked was long term exposure to UV radiation, even as far north as upstate New York. This started appearing about 20 years after initial install. This proprietary insulation system did not required a tape shield, making bending radius and installation handling less risky, installed in 12" rung spacing 6" side rail aluminum ladder tray, thousands of feet. The construction of stress cones is also simplified, simple Raychem heat shrink assemblies were installed, the concentric neutral bundled and grounded through the stress cone base.

Much of the tray system has ended up covered, so the ampacity was reduced. The tray and supports were kept a respectable distance from mill roadways, as suggested, installed in the late 1970s to mid 1980s, it was a massive improvement in reliability over the previous open pole line

Would this be plastic tray, by any chance?

Good point ,PWSlack !

<...minimun Distance for Authorized Person, for vehicular transit?...>

Like this?

It is worrying to countenance that people are working close to <...33kV...> without access to appropriate standards to work with and appropriate training, to the extent that the situation deserves an enquiry to an anonymous international Engineering forum for advice...

You will find your answer in your local electrical codes. Since we do not know where this is, we cannot help you.

Also, only authorized people should work on power distribution wiring, particularly at 33kV. Authorized people know which codes apply. STOP!

Cable tray/ladder with 33kV installed.

1. Distance from what? Other 33kv cables, instrument cables, other LV cables?

Answer is 320mm spacing. Instrument cables are installed on a separate cable tray, always. If the instrument cables are fibre optic, no spacing is required.

2. Distance when crossing internal road ways, pedestrian walkways within a factory area?

Answer: the height of the tallest vehicle that will travel the road, plus a clearance of at least 500mm. Alternately use the overhead line clearances of 7.5m (min).

3. Minimum distance from someone trying to touch the installed cable on the cable tray?

Answer: 320mm as sheath currents can be carried on the PVC/XLPE sheath.

Anyone working on cables should know these minimum allowable dimension, they are standards used world wide and don't change.

IEC, ASTM, ANSI, BS, CIGRE, standards can be found on line. And, if this is being worked, I have to ask, why are the standards not on site as per the contract document requirements. All standards are found/referred to, in the front of the contract doc. That will be to thick dusty document(s) on a shelf, that no one reads.

Not sure what your jurisdiction is, but where I am (Ontario, Canada) minimum distances are covered in the Occupational Health and Safety Act.