Thread: Wire Shielding

Any1?

My commercial machine had the tinned copper shield but im certain its high frequency I am looking to block out and also the wire I bought from the US ages ago had the aluminium foil shield.

Hi

I know where to buy shielded cable in perth by the meter, but high or low frequency I dont know, all I can say on that one is any shielded cable is better then none.
The larger cables seem to have braided shielding and the small data cables have aluminium foil shield.
Cheers michael

Was that the $3.50 for the 1.5mm2 4 core?

I just found that site again and I dont know why I didnt look but they have a branch up around Newcastle. I'll shoot them off an email and see if they have stock. 5 hour trip there and back



How was the wire you bought from Electcables is it very flexible?

It been awhile and I am going off memory but if I recall correctly there are a few factors to consider such as the frequency of the interference etc. As a general rule foil provides about 15 dB of shielding, braid provides about 30 dB of shielding and braid over foil provides about 40 dB of shielding.

Here is a quick overview:

Calvert Wire & Cable: Shield Types Application Guide

If it is a critical aspect of your system design I would recommend some specialist advice.

yes $3.50 mtr, its very flexible which mine was running at 100mm radius on my cnc router.
To give you some idea, its a extension lead with braided wire and a clear sleeve.
here is some pictures of 4 and 3 core both 1.5mm


Cheers Michael

Originally Posted by mkc2

yes $3.50 mtr, its very flexible which mine was running at 100mm radius on my cnc router.
To give you some idea, its a extension lead with braided wire and a clear sleeve.
here is some pictures of 4 and 3 core both 1.5mm


Cheers Michael

Cheers for that, I'll give their NSW branch a go I don't mind driving so I might try and grab some early next week or see what they charge for shipping.

Thanks for the info and link grunto, I'll give the braid a go as it seems to be the right type for the cnc machines as no one is reporting any problems with them and I now see a few users using the braided stuff.

Ch4iS,

Did some more reading on foil vs braid and generally braid wins out so I think it is the way to go. Getting a connection on braid seems a lot easier as well.

What is the part number of the cable you are using? I was looking at something like the ProtoFlex cable for a CNC build starting in the new year. I like the look of your cable (seems pretty rugged) and was wondering if it was similar. What made you go with 4 x 1.5mm - seems rather large (but your machine may be a lot bigger than mine).

Hi
cable is --Siemens Australia 5EMC4105 4x1.5 sq.mm (0,6/1 kv)
I use this on 72vdc 1070 ozin motors.
Also will change the router 240v lead to a 3 core shielded cable as this causes the most interferance .

Cheers michael

Originally Posted by grunto

Ch4iS,

Did some more reading on foil vs braid and generally braid wins out so I think it is the way to go. Getting a connection on braid seems a lot easier as well.

What is the part number of the cable you are using? I was looking at something like the ProtoFlex cable for a CNC build starting in the new year. I like the look of your cable (seems pretty rugged) and was wondering if it was similar. What made you go with 4 x 1.5mm - seems rather large (but your machine may be a lot bigger than mine).

4x1mm2 would be more than plenty for stepper motors I would think. My commercial machine originally had 4x0.75 (not sure if thats mm2 or mm diameter). Mine are Nema 34 motors and around the 500 oz-in mark. But the 1.5KW spindle had 1.5mm wiring.


{EDIT}

http://www.engineeringtoolbox.com/aw...uge-d_731.html

1mm2 is almost 17 AWG, Nema 23 motors should only need 22 AWG.

My largest motor 1200oz-in Nema 34 motor uses 18 AWG wire for reference, so the 1.5 would be able to handle some massive motors.