This question, perhaps being Electrical Code related, might be better under the 'Electrical Engineering general discussion' forum.

Good luck.

(Edit: I see that didn't work out.)

I mean EMC standard not electrical isolation
because it will be induction currents from transformers to Data center + noise + transmit Emission

What does the transformer manufacturer recommend?

Z

Seems to me that depends on how much hardening you've got in your data center; presumably, if your data center were in a Faraday cage, you could be as close as you want. barring getting people that close to do install or maintenance. You can arbitrarily harden equipment and wiring, people, not so much.

See https://emfinfo.org/guidelines-distance.html for some numbers

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Thank you very much
but i think 50 hz magnetic fields with its noise and harmonics less than 1KHZ will not be shielded by faraday cage

Low frequency 50 HZ magnetic field will not be shielded in faraday cage because it is not transmitted field

i have two choices :
1- to shield: what is the specification to shield 50 hZ magnetic field
2- changing the data center place to 25m distance , is this separation space adequate?and what is the standard or code?

It's presumably very unlikely that EMI would be the deciding factor.

They should certainly be physically separated to contain and isolate failures, such as transformer explosions or fires.

Once there's a reasonable gap for practical and safety reasons, the EMI is almost certainly a non-issue.

WHy 2000KVA transformer + 1600 KVA 20/0.4v their magnetic fields with nominal currents 2887A

I think the magnetic field will be considerable in specific distance around the station or the transformers

any new help?

For larger context: Are you being asked to install a data center directly adjacent to these existing high power transformers, and you're quite reasonably uncomfortable with that, and you are seeking some justification for arguing against this arrangement?

Or is this a subcontractor's plan?

Are the transformers already in place? Can you bring in a laptop and see if it's corrupted by the EMI?

Are these transformers needed to feed your huge data center? How big is your data center?

Have you mentioned the distance yet?

Zappedagain suggested that you to check with the transformer manufacturer. Have you done that yet?

Have you considered shifting your focus away from just EMI as the only possible justification? Have considered other factors, such as safety or emergency considerations? Once you allow a reasonable 10m+ safety radius for the transformer fire and access for a firetruck, then EMI is presumably a non-issue.

Any response to these points?

VE1BLL , thank you very much,

This is unconstructed project yet

I have only the architecture drawings and the transformers are in the second hall

i want standards or code to follow in design
the transformers are for the hall tower but the data center is in the ground floor only in area about 20*10 m2
any spacing distances you could help me i will be glad for your kind help

Again, you are asking for protection for a vague "data center" of unknown hardening. If this is such a concern, throw up a Faraday cage around the room; well-ground chicken wire would do the job, but you can go with regular chain-link fencing, again well-grounded. Your power source connections should backed up with surge protectors.

I suggest you contact someone who does this sort of thing for a living.

TTFN (ta ta for now)
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