MV cables with LV cables
MV cables with LV cables
(OP)
I would like to ask if it is allowed lay MV cables (e.g. 20 kV) in tunnels or wells where LV power/control/monitoring cables are laid. See photos, please.
http://snag.gy/p1DsC.jpg
http://snag.gy/wswzq.jpg
http://snag.gy/Jb5o7.jpg
http://snag.gy/1iGwA.jpg
http://snag.gy/p1DsC.jpg
http://snag.gy/wswzq.jpg
http://snag.gy/Jb5o7.jpg
http://snag.gy/1iGwA.jpg






RE: MV cables with LV cables
1)the manhole, it seems to me, is very small-no room for cable pulling or cable joint if it will be necessary once, no ladder is provided and no grounding means.
2) the cables are not supported by cable trays.
3) for control cable no steel conduit or other separate enclosed magnetic raceways is provided in order to reduce the EMC.
4)medium voltage cables-it seems to be single core cables-all 3 phases have to run in a single duct.
RE: MV cables with LV cables
instead of " in order to reduce the EMC" has to be " in order to reduce the EMI".
2)If the low voltage cables[power or lighting] are separated by a distance of 1 feet from the medium voltage cable it is permitted to be laid in the same room. However, NEC Art.392.10(L) requires a separation "by a solid fixed barrier of a material compatible with the cable tray."[no distance required].
3) If the medium voltage cable is labeled as "MC" it is permitted to be laid in the same cable tray with low voltage cables.
MC=metal clad cable- enclosed in an armor of interlocking metal tape, or a smooth or corrugated metallic sheath.[it seems to me it is not your case].
RE: MV cables with LV cables
RE: MV cables with LV cables
Seperate sleeve for MV, LV, Tel, and fibre optic cables, care should be taken on bending radius of MV and LV cables, one of the photos looks like a dogs dinner.
Padlock01
RE: MV cables with LV cables
Dapo18
RE: MV cables with LV cables
Hope this help, and, BTW I would fire this contractor; poor work. I think everyone agrees :)))