Control panel wiring

[pauly]

I would like to get some feedback from the forum regarding control panel wiring and in particular segregation of wiring.
I happen to be part of a business who insist on using double trunking to separate 24 volts and mains. By mains I mean 110v and above.
All cable is tri-rated cable
I can understand comms/data cable segregation and high power cabling.
I have yet to find any guidance from any European standards either.
All input welcome

 

[lfe]

I usually used the system of putting two main vertical conduits on each side edge of the panel, the right one for the power cables and the left one for signals and 24V.

The terminals at the bottom well segregated with the power on the right and the 24V and signals on the left.

In the horizontal ducts it is not possible to achieve total but close segregation.

 

[Rob...]

Wiring must have an insulation rating greater than the maximum voltage present in the trunking.

In a nutshell, this is the minimum requirment.

Generally tri rated has an insulation rating of 600v.

 

[Jeev]

My suggestion would be to try and understand the requirement in its entirely.

If standards exist in the country of use then that is the place to start. For example, a lot of the systems I have been involved in are subject to AS3000 (Wiring Rules) and AS4024 (Safety Of Machinery Series), which have sections derived from a number of IEC's, EN's and ISO's (Type A, B and C). Additionally, you need to comply with any EM regulations and directives that may, for example suggest that certain cables need to be earthed or shielded, or certain signals can not be influenced by external sources or generate interference externally.

There are hardware or equipment specific requirements for items like sensitive measurement equipment, or vision systems, and then there are customer specific requirements for industries like mining, utilities, food/beverage, defence and construction. Typically these will be on an installation by installation basis.

You need to look at the installation subjectively to determine what is and isn't appropriate, and in the case of segregation; there could be a great many reasons to do it.... Or it could be that one person said that it's how they did it in the past at X organisation (Whether that is a requirement in your own organisation or the customer's/site's request), so really there may be no reason to do it at all.