DLO Insulation Rating Question - Canada

[Coco_HueHueHue]

Hello,

I have a question about DLO insulation Rating.

I always used them before into 600V distribution. So i never cared about the insulation rating of 1000V vs 2000V.
But, into an installation, the 2kV insulation rating is required, but this is not a typical rated voltage for cables in Canada. It is more an American voltage standard from my experience browsing UL cable catalogues.

So when i look into a datasheet like this one:

https://ecat.eleknet.com/PIM_Docs/Docs/STEP_ASSETS_PDF/13073077.pdf

Do you think CSA authorizes the use of DLO at 2kV in Canada instead of limited to 1kV?

My personel research led me to a yes.
CSA C22.2 No. 38 mentions a minimum insulation level of 1.14 mm for 2000V cable, and this one in the datasheet has 2mm, so i believe i have my answer.

Just curious to know what anybody else thinks about this?

Thank you!
Julien

 

[waross]

Call Texcan and order 2000 Volt rated and marked DLO cable.
Is the voltage 2000 Volts or is this a consultant's specification requirement?
By the way, Table 11 of the 2015 Edition of the CEC lists DLO voltage as 2000 Volts. Has there been a recent code change?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Coco_HueHueHue]

I did notice that Table 11 in the Code with a 2000V specification.
Last version of the Code mentions the same thing. But, that Table 11 is for "Portable" installation. I am not sure i can apply it for a Tray or Conduit or Other permanent installation.

Actually, I am kind of the consultant specifying a DLO cable that needs 2kV insulation haha.
But i am not sure we can use those products here and wanted other people opinion on the topic. Worst case, i guess it will need to be 5kV CSA as i know those exists.

Btw, i did call TEXCAN, and the person i spoke to doesn't know!

Thanks!

 

[waross]

Did you notice table 12E?

Table 12E
Allowable ampacities for Type DLO cables in
a permanent installation in cable tray
(See Rules 4-006(6) and 4-040(4) and Tables 5D, 12B, and 12C.)

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Coco_HueHueHue]

Hi Waross,

Yes, i did notice it.
But, digging hard yesterday i think i answered myself. And i honestly think that CSA 2kV DLO cannot be used at 2kV in permanent installations, but only in portable installations in Canada.

I found article 4-040 that appears to be very clear that a DLO cable can be used for a permanent installation if it is 1/0 in size or bigger and TC rated. But it should be used in conformity to the conditions of TC cable (rule 12-2202) and as listed in Table 19 (which doesn't include specific DLO details, but only like RW-90 details).

This explains why the datasheet of the manufacturer mentions:
CSA 2kV DLO
CSA 1kV RW-90

It seems to all depend on the installation. I believe article 4-040 answers my question. I had never noticed/read this article before and i don't think many people did. In Canada, there is almost no reason to have a 2kV rated cable... so this specific detail is almost never used... I had the question here because of the rotor field voltage from an excitation system that is around that range of voltage. But it is really not typical. I never asked myself that question while working with 600V installations as 1kV is more than enough!

Coco

 

[Gr8blu]

Coco:
DLO cable rated for 2 KV has been used in the mining, metal rolling, and transportation industries for better than 60 years (in Canada and elsewhere) ... for both permanent and temporary installations. You'll find a lot of it wherever there were fairly large DC machines being used to power process industries (since they invariably operate at < 1500 V), as the mechanical flexibility was the key issue.

Cable with higher voltage ratings will almost certainly contain silicon in some fashion: if the cable is used in proximity to a sliding electrical contact (think brush on commutator for DC, or brush on collector / slip ring for AC) then the higher-voltage cable is not advised due to the potential for off-gassing from the silicon-bearing cable material.

A little bit of silicon off-gassing goes a long way: to put it in perspective, 8 or 9 drops of food coloring in a swimming pool holding 13500 US Gallons is about the same level required to damage the film buildup on commutator or collector.

Converting energy to motion for more than half a century

 

[Coco_HueHueHue]

Gr8blu:

Thank you for your input and providing less than 2kV cable application. With a little under 10 years experience, i haven't touched too many installations with DC motors. All i have seen is AC motors with VFDs nowadays

But, my main question in this topic was to clarify when we can use DLO at a 2kV rating. I think that 2kV is authorized on DLO cable only for what the Canadian Electrical Code considers as a portable feeder (as per Table 11), not a permanent one as described by article 4-040 (and Table 19).

For mining, i understand they have their specific electrical code. But i never worked with it, so they might have the right to use it at 2kV.

By the way, would you have any link/info on the off-gassing phenomenon? Never heard of that before and i am interested into reading on this.
And, for your info, for big synchronous generator, i have in the past supplied cables rated 5kV - 500MCM with EPR insulation / Neoprene jacket (so no PVC if i am not mistaken). Very expensive and specified product though

 

[waross]

Silicon: Do not use RTV silicon anywhere around brushes. Thanks for the info on concentration, Gr8blu.
I would have a chat with the AHJ and ask for special permission.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!