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Is It Mandatory to Separate 230V AC and 24V DC Control Wiring in a VFD Panel According to IEC Standards?

d0789201

Electrical
Feb 6, 2025
2
Because my English proficiency is not very good, the following description was translated using GPT.

In this post, I would like to ask: Does the IEC standard strictly require 230V AC and 24V DC control wiring to be physically separated in a VFD control panel? The main MCCB is rated at 600A, and the VFD is 300HP. The main voltage is 400VAC, and the VFD will also be connected to a DC power source (DC bank) at approximately 570VDC.

Thank you all!
 
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Welcome to the forums, Dee.

One of the more code-knowledgeable members here will likely answer your query . . .
 
IEC requires separate runs for certain voltage breakpoints. However, everything I've been able to track down (which isn't all; there is, by a long shot) has no real hard stance on anything below 1000 V. However, knowing what we do *now, vs back in the early 1970s) about how harmonic content and magnetic fields can affect both power and control circuitry, it makes a lot of common sense to have some form of separation or shielding.

If you are AT ALL worried that the data signal might be corrupted by transient effects from the power signal, include the physical separation or shielding.
 
Only standards for separation I know require separation of class 2 circuits, separation of hazardous location circuits using energy isolators and separation of circuits where the lower voltage wire insulation isn't rated for the higher voltage.

24V and 230V could be together as long as it's standard circuits and the 24V wire insulation was rated for 230V.
 
Thank you all for the information.
It looks like I'll have to coordinate with the customer again.
Thanks!!
 

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