Shielded Tray Cable vs. VFD Cable

[woods95662]

Can I use shielded tray cable in liue of VFD cable? There would be multipal runs of this cable in a gutter. I would think it would be ok but never like to assume anything. Any help would be appreciated.

 

[cadpoint]

Here is the history of like posts on this forum, "shielded cable - VFD "

http://forums.mikeholt.com/search.php?searchid=1006103

Don't worry about locked threads you can still read them just not respond to them.

Welcome to the forum.

 

[weressl]

Can I use shielded tray cable in liue of VFD cable? There would be multipal runs of this cable in a gutter. I would think it would be ok but never like to assume anything. Any help would be appreciated.

What kind of 'shielded' cable? You need to be more specific.

You also need to be more specific about the motor size, type and the drive as well as the distance between the motor and the drive. The manufacturer of the drive will be specific in their instructions on what you can use for your application. ASD rated cables (also need to) have a higher insulation level than ordinary cables.

 

[Jraef]

Shielded tray cable is better than having no shielding, but "VFD" cable typically has more ground current capacity, usually 3 separate GCs spaced evenly with the power conductors as opposed to one. That can be important in some applications.

Read this, especially Chapter 1
http://literature.rockwellautomation.com/idc/groups/literature/documents/in/drives-in001_-en-p.pdf

 

[cadpoint]

Thanks for the replies.
I didn't find the PDF you were talking about, but they do sum it up pretty well on the main page:

It was the little picture on the main page.... but your right, this was the response...

(a) 404 (error)

We're sorry, but the file or content you requested could not be found, or has been moved. From time to time new product content is added and we update the URLs to accomodate our growth.
You can find specifications, brochures, architectural and CAD resources and other information about Wheatland products in the Products and Solutions section.
Please visit the site map for a complete list of the main sections on this site. The search feature will also help you locate content quickly (upper right on the page).

Ok let me say that I was in on a kiddle, for me the full aspects of thread posting is shaky, yes I've talked to the overseer... I usually compose in a word program.

I frankly crashed posting the first time because one has to have all their posting thoughts together and not compare it's usage that migth be obtainable of all the aspects of things that are availabe on a PC / Mac.

It's memory usage (Kindle) doesn't address all the exact usage of thread posting and can be lacking,
don't ty it.

 

[mike_kilroy]

....There would be multipal runs of this cable in a gutter....

what does this part mean? sounds like you would have more than 1 set of vfd driven motor leads tossed in there together?

Just curious how many motors worth of cables will be in the same gutter if so?

If this is the case, I wouldn't go without an individual vfd shielded cable for each motor as you may end up with interaction between the various motors that cause you much more cost tracking down and fixing than the initial investment in a bit more expensive cable.....

 

[weressl]

what does this part mean? sounds like you would have more than 1 set of vfd driven motor leads tossed in there together?

Just curious how many motors worth of cables will be in the same gutter if so?

If this is the case, I wouldn't go without an individual vfd shielded cable for each motor as you may end up with interaction between the various motors that cause you much more cost tracking down and fixing than the initial investment in a bit more expensive cable.....

Drive manufacturers - sometimes - specify the minimum parallel distance requirement from other power cables. Not only unshielded parallel runs of multiple ASD can create unstable control, but they can also damage the drives themselves.

 

[woods95662]

Hi guys I had no idea this had been posted and replied to I didn't receive any notifications. I got it figured out and I appreciate the help! Basically it's the safe bet to just use VFD cable unless it's the only cable in a single conduit in which case you can just use THHN. Otherwise you're taking chances running multipal cables in a conduit for a VFD and not using VFD cables. The extra shielding in VFD cable gives you that extra protection plus it carries a full size ground.

 

[Jraef]

Hi guys I had no idea this had been posted and replied to I didn't receive any notifications. I got it figured out and I appreciate the help! Basically it's the safe bet to just use VFD cable unless it's the only cable in a single STEEL conduit in which case you can just use THHN. Otherwise you're taking chances running multipal cables in a conduit for a VFD and not using VFD cables. The extra shielding in VFD cable gives you that extra protection plus it carries a full size ground.

Fixed it for ya.

We can ASSUME you knew that you meant steel conduit, but someone reading this thread in the future may not undersrtand that and think it's OK to run THHN for VFD to motor runs in PVC conduit. It is not.

PS:
"Notifications" is something you must SELECT, the default is to NOT allow notifications. Go to "My Profile" in the top left, then click on Forum Actions on the upper rigth, then click on General Settings. You will see a "Subscribe" drop-down box. Subscribing means you will get an email notification whenever there is a post in a thread that you started or replied to.