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Protection study on existing LV network with obsolete equipment

Protection study on existing LV network with obsolete equipment

Protection study on existing LV network with obsolete equipment

(OP)
A client who recently had a factory burn down following an electrical fault has asked me to carry out a discrimination study across his network at another plant. The supply is comprised of a 300kVA 400v TPN supply, MCCB main switchgear with 15 downstream type B MCB sub main boards.
The problem is most of the kit is out of date and few details are available for the performance of the devices, the equipment is by a number of manufacturers and the fault levels are highish.
I have measured the FLs at the source and at all 15 boards and final circuits and am ready to carry out the study but I am unable to find certified coordination data relating to the obsolete devices.
Consequently, I am stuggling to I predict with any real confidence the performance of a circuit, for example, comprised of a 400A HRC fuse in series with an obsolete 250A Hager MCCB in series with an obsolete 100A MEM MCCB with a FL of 6kA flowing.
Any thoughts ?

RE: Protection study on existing LV network with obsolete equipment

Try contacting original manufacturers (or anyone who bought them out) for the data you need. Other than that you can only state the facts as you know.

 

 

Rafiq Bulsara
http://www.srengineersct.com

RE: Protection study on existing LV network with obsolete equipment

Hager and MEM are both very much in business so they should be able to provide the information. MEM are now part of Eaton. You might have to be persistent to get past the trained monkey 'customer support'.
 
  

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If we learn from our mistakes I'm getting a great education!
 

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