Minimum distance between A and B Batteries

[BINGMD]

138kV substation with 125 VDC battery A and battery B for protection A and B, trip coil 1 and trip coil 2, etc.

The distance between two batteries is about 5 feet.

I commented too close but have not find any reference to prove my feeling.

Could you please help to enlighten me on this by providing some standards?

Thank you,
Regards,
Bing

 

[turbinetony]

5 feet should be sufficient to prevent induced voltage from the AC 138KV line.

regards,
Steve

http://www.powerplantforum.com

learn. educate. network

 

[rcw retired EE]

Reliability guidelines require physical separation so a single event like a fire or short circuit does not defeat both primary and alternate protection systems. But I haven't seen any specific guidelines, it is left up to "good engineering."

Five feet seems small. Maybe adding a barrier between the two batteries to prevent a common fire damage or adding fire suppression in the room would create the same reliability.

 

[BINGMD]

Thank you for your answers.

 

[cuky2000]

There are not code or specify guideline in any standard that i know.
Common sense, experience and apply good engineering practice could be used for engineeing judgement to avoid single point of failure.
A balance between cost, safety and system reliability should be considered.
I hope this help.

 

[marks1080]

The company I work for recently adopted the rule of having A and B protections in separate buildings. I know it is a little extreme, but they are beinginng to impliment it. It's hard to point to a clear reason why this might be over kill (i'm sure the bean counters did try) but at the end of the day it dose mean more work for me

 

[davidbeach]

marks1080, can you say who you work for?

 

[marks1080]

David,

I'm a protection and controls engineer (like yourself) with HydroOne Networks, the main utility in Ontario.

 

[slavag]

Hi Marks1080.
Separate building it's really extreme.
Are you talking about A,B protection systems or battery or about both?
Regards.
Slava

 

[lz5pl]

Usually we put batteries in separate rooms (in separate buildings is really extreme for me). But if they are in one room at least some fire-protection barrier should be between them, as well as their cables to be run on separate routes.
I haven't seen some standard/code requirement, these rules are just common sense and practice.


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It may be like this in theory and practice, but in real life it is completely different.
The favourite sentence of my army sergeant

 

[marks1080]

Slava,

Yes i know it is extreme. And yes I am talking about both.

This is a new initiative, and has yet to be implimented (as far as I know). We look after hundreds of stations so I can't speak for them all. I do know there are plans to start putting this into action.

Personally, I think it does make sense, but it is at a huge cost. I think it is being done here because more and more private companies are getting into the generating market. There is more pressure on us (as the public utility) to make sure these guys can sell their power 24/7. I can only imagaine there is a heavy political influence too, but I tend to stay away from those conversations as I am already losing my hair faster than I want.

 

[marks1080]

Also, more to the topic, yes, put your A and B batteries in atleast separate rooms. I cannot reference a code or standard on this, but it is generally bad practice to put both A and B battery banks in the same room.

 

[slavag]

Marks, thanks a lot for very intresting information.
If it's start in one place...., after few years we'll see it
as standard in many companies and countries.
bay the way isn't so strange.
Very intresting !!!!!!!!!!!
Best Regards.
Slava