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Medium voltage wire

Medium voltage wire

Medium voltage wire

(OP)
I need to connect some bare, live parts in electrical equipment and would like to use insulated wire to do it because space is limited.  Problem is, voltage to ground is 7200 V.  Because distances are short, shielded cable is not practical.  Anybody know of a source for such wire?  I'm looking at a #1 AWG or 50 sq. mm.

RE: Medium voltage wire

TMD, I don't mean to offend you, but the fact that you are asking this question indicates that you are not qualified to perform this installation. Or maybe you should provide more info.
MV cable manufacturers are commonly known to experienced people, and this type of installation can be done by experienced linemen with the proper equipment on an exposed overhead line, but even then it is a very hazardous operation.

RE: Medium voltage wire

We buy it from a Distributor called "Industrial Wire & Cable"  What you want is 15kV "jumper" or "switchgear" wire.  I just checked our inventory and the wire labeled "jumper" was solid conductor with cross linked poly insulation.  The wire labeled "switchgear" was stranded and used EPR (red synthetic rubber).  

When you install it, keep the phases from touching and isolated from ground.  It really is intended to be run in air and where necessary supported on insulators.  It will last for years in dry conditions laying on metal and one phase touching another but the proper way to install is as mentioned above.

RE: Medium voltage wire

We have used 15kv "Jumper" cable in the past, and the result have been excellent. However,  jumper cable is made for temporary installations and not for permanent use in an enclosures.

We used the cable in an enclosure (here in Canada) and CSA would not approve the equipment, as per above remarks.  Now to get equipment approved we must manufacture small pieces of CU bus, and insulate it to CSA requirements, or get the stress cones out... which is totally impracticle.

Although we have had no problems with the cable in the past, this is where we stand...





RE: Medium voltage wire

(OP)
tulum:
Seems like our problems (and proposed solutions) are similar (as is our location).  Thanks.
Our product doesn't need to be CSA approved, but it must pass the usual high potential test and an impulse test.  We are looking at using 5 or 8 kV unshielded cable, supported on a suitable insulating structure.  Additional insulation will be provided by phenolics or plastics.  The initial plan was to use bare bars insulated with space (air) and solid barriers, but the cable seems more practical.

RE: Medium voltage wire

I have been looking at 7.5kv rated, unshielded "machine tool and apparatus wire" from Rome for a simular application. AWG#8 and up

RE: Medium voltage wire

Suggestion: If the equipment happens to comply with an industry standard, the equipment modification should be compatible with that industry standard, else the equipment would be considered not meeting the industry standard. Often, any modifications that are done without consulting the equipment manufacturer and the equipment associated industry standard void the industry standard label, e.g. UL.

RE: Medium voltage wire

Visit
http://public.ansi.org/ansionline/Documents/Standards%20Action/Archives/2002%20PDFs/SAV335.pdf
for:
BSR/UL 1072-200x, Standard for Safety for Medium-Voltage Power Cables (revision of ANSI/UL 1072-1988)
Covers shielded and nonshielded, single-and multiple-conductor Type MV (8 - 1/0 AWG, rated 5000 - 35000V) medium-voltage power cable.
Multiple-conductor cables may include one or more individually jacketed nonconductive optical-fiber members. These electrical and hybrid electrical/optical-fiber cables are for use (optical/electrical functions associated in hybrid cable) in accordance with Article 328 and other
applicable parts of the National Electrical Code (NEC) ANSI/NFPA
70-2002.

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